Publications
2026 |
Yang, Kou; Bi, Xueli; Zhong, Haibin; Wang, Juncheng; Luan, Yanju; Zheng, Shushen; Andreeva, Daria; Novoselov, Konstantin; Zhang, Shanqing Stimuli-responsive graphene oxide composites: working mechanisms, design strategies, and applications PROGRESS IN MATERIALS SCIENCE, 158 , 2026, DOI: 10.1016/j.pmatsci.2025.101649. @article{WOS:001660716900001, title = {Stimuli-responsive graphene oxide composites: working mechanisms, design strategies, and applications}, author = {Kou Yang and Xueli Bi and Haibin Zhong and Juncheng Wang and Yanju Luan and Shushen Zheng and Daria Andreeva and Konstantin Novoselov and Shanqing Zhang}, doi = {10.1016/j.pmatsci.2025.101649}, times_cited = {0}, issn = {0079-6425}, year = {2026}, date = {2026-04-01}, journal = {PROGRESS IN MATERIALS SCIENCE}, volume = {158}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {Stimuli-responsive graphene oxide (GO) composites have emerged as a frontier in smart materials research due to their tunable physicochemical properties and dynamic responsive capabilities to various stimuli, including physical stimuli (such as temperature, light, strain/pressure) and chemical stimuli (such as pH, water, moisture, and chemical species). The unique twodimensional structure of GO, distinguished by its exceptional specific surface area and abundant oxygen-containing functional groups, provides an ideal platform for integrating diverse responsive moieties through covalent/non-covalent modification strategies. This review systematically summarizes the response mechanisms to these stimuli and examines recent advancements in tailoring GO-based composites with programmable responsiveness to environmental stimuli, including thermal, pressure, pH, humidity, and specific biochemical signals. By analyzing their evolving design strategies, we elucidate emerging applications in flexible sensors, photocatalysis, photo-electrocatalysis, ion/gas separation membranes, and environmental remediation technologies. We also envisage critical perspectives on future research and development directions of stimuli-responsive graphene oxides.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Stimuli-responsive graphene oxide (GO) composites have emerged as a frontier in smart materials research due to their tunable physicochemical properties and dynamic responsive capabilities to various stimuli, including physical stimuli (such as temperature, light, strain/pressure) and chemical stimuli (such as pH, water, moisture, and chemical species). The unique twodimensional structure of GO, distinguished by its exceptional specific surface area and abundant oxygen-containing functional groups, provides an ideal platform for integrating diverse responsive moieties through covalent/non-covalent modification strategies. This review systematically summarizes the response mechanisms to these stimuli and examines recent advancements in tailoring GO-based composites with programmable responsiveness to environmental stimuli, including thermal, pressure, pH, humidity, and specific biochemical signals. By analyzing their evolving design strategies, we elucidate emerging applications in flexible sensors, photocatalysis, photo-electrocatalysis, ion/gas separation membranes, and environmental remediation technologies. We also envisage critical perspectives on future research and development directions of stimuli-responsive graphene oxides.
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Alharbi, Osamah; Yuan, Yue; Zheng, Wenwen; Ping, Yue; Pazos, Sebastian; Alshareef, Husam; Zhu, Kaichen; Lanza, Mario Nanodot conductive atomic force microscopy MATERIALS SCIENCE & ENGINEERING R-REPORTS, 169 , 2026, DOI: 10.1016/j.mser.2026.101187. @article{WOS:001674879800001, title = {Nanodot conductive atomic force microscopy}, author = {Osamah Alharbi and Yue Yuan and Wenwen Zheng and Yue Ping and Sebastian Pazos and Husam Alshareef and Kaichen Zhu and Mario Lanza}, doi = {10.1016/j.mser.2026.101187}, times_cited = {0}, issn = {0927-796X}, year = {2026}, date = {2026-04-01}, journal = {MATERIALS SCIENCE & ENGINEERING R-REPORTS}, volume = {169}, publisher = {ELSEVIER SCIENCE SA}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {Gate-all-around (GAA) transistors and memristors are two key electronic components for the semiconductor industry, as they can enable high-performance computation and memory. State-of-the-art devices contain a 700-100,000 nm2 insulating thin film exposed to electrical fields, and understanding its progressive degradation and breakdown is essential to build reliable devices. Investigations in this direction must fabricate test structures and/or devices of similar sizes, otherwise the conclusions extracted are not applicable. Many research groups use electron beam lithography, but this technique introduces polymer residues and leads to low fabrication yields due to the complex lift-off process. Some groups use conductive Atomic Force Microscopy (CAFM), which employs an ultra-sharp conductive tip to analyse the properties of a material at small areas ranging from 1 to 600 nm2. However, the currents registered by CAFM strongly depend on three parameters that are difficult to control: the radius of the probe tips, the spring constant of the cantilever, and the relative humidity of the environment. Therefore, a major problem of CAFM is reproducibility. Moreover, the minimum current densities that standard CAFM can detect range from 0.16 to 100 A/cm2, but that is insufficient to study gate dielectrics for low power applications (that requires analysing values below 0.01 A/cm2). Here we present nanodot CAFM, a measuring protocol that consists of placing the probe tip of a CAFM on metallic nanodots patterned on the surface of the material under test. These structures cover areas between 700 and 10,000 nm2, and they can be easily deposited on any arbitrary sample using a standard evaporator and a cheap aluminium anodic oxide template as shadow mask. Our experiments demonstrate that this setup is insensitive to relative humidity changes from 55 % to 4 %, deflection setpoint changes from -0.5 to 1 V, spring constant changes from 0.8 to 18 N/m, and tip radius changes from 2 to 200 nm, leading to a very high reproducibility. Moreover, this setup allows analysing current densities below 10-2 A/cm2, which extends its range of use. Our approach can help the community to make industry-relevant studies with a high throughput without having to undergo expensive, slow, and low-yield nanofabrication processes (such as electron beam lithography or multi project wafer tape outs).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Gate-all-around (GAA) transistors and memristors are two key electronic components for the semiconductor industry, as they can enable high-performance computation and memory. State-of-the-art devices contain a 700-100,000 nm2 insulating thin film exposed to electrical fields, and understanding its progressive degradation and breakdown is essential to build reliable devices. Investigations in this direction must fabricate test structures and/or devices of similar sizes, otherwise the conclusions extracted are not applicable. Many research groups use electron beam lithography, but this technique introduces polymer residues and leads to low fabrication yields due to the complex lift-off process. Some groups use conductive Atomic Force Microscopy (CAFM), which employs an ultra-sharp conductive tip to analyse the properties of a material at small areas ranging from 1 to 600 nm2. However, the currents registered by CAFM strongly depend on three parameters that are difficult to control: the radius of the probe tips, the spring constant of the cantilever, and the relative humidity of the environment. Therefore, a major problem of CAFM is reproducibility. Moreover, the minimum current densities that standard CAFM can detect range from 0.16 to 100 A/cm2, but that is insufficient to study gate dielectrics for low power applications (that requires analysing values below 0.01 A/cm2). Here we present nanodot CAFM, a measuring protocol that consists of placing the probe tip of a CAFM on metallic nanodots patterned on the surface of the material under test. These structures cover areas between 700 and 10,000 nm2, and they can be easily deposited on any arbitrary sample using a standard evaporator and a cheap aluminium anodic oxide template as shadow mask. Our experiments demonstrate that this setup is insensitive to relative humidity changes from 55 % to 4 %, deflection setpoint changes from -0.5 to 1 V, spring constant changes from 0.8 to 18 N/m, and tip radius changes from 2 to 200 nm, leading to a very high reproducibility. Moreover, this setup allows analysing current densities below 10-2 A/cm2, which extends its range of use. Our approach can help the community to make industry-relevant studies with a high throughput without having to undergo expensive, slow, and low-yield nanofabrication processes (such as electron beam lithography or multi project wafer tape outs).
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Zawadzka, Natalia; Vaklinova, Kristina; Wozniak, Tomasz; I, Mihai Sturza; Kohlmann, Holger; Watanabe, Kenji; Taniguchi, Takashi; Babinski, Adam; Koperski, Maciej; Molas, Maciej R Electrically modulated light-emitting device driven by resonant and antiresonant tunneling between Cr2Ge2Te6 electrodes 2D MATERIALS, 13 (1), 2026, DOI: 10.1088/2053-1583/ae2520. @article{WOS:001634241900001, title = {Electrically modulated light-emitting device driven by resonant and antiresonant tunneling between Cr2Ge2Te6 electrodes}, author = {Natalia Zawadzka and Kristina Vaklinova and Tomasz Wozniak and Mihai Sturza I and Holger Kohlmann and Kenji Watanabe and Takashi Taniguchi and Adam Babinski and Maciej Koperski and Maciej R Molas}, doi = {10.1088/2053-1583/ae2520}, times_cited = {0}, issn = {2053-1583}, year = {2026}, date = {2026-03-01}, journal = {2D MATERIALS}, volume = {13}, number = {1}, publisher = {IOP Publishing Ltd}, address = {No.2 The Distillery, Glassfields, Avon Street, Bristol, ENGLAND}, abstract = {Exploring the electron tunneling mechanisms in diverse materials systems constitutes a versatile strategy for tailoring the properties of optoelectronic devices. In this domain, bipolar vertical tunneling junctions composed of van der Waals materials with vastly different electronic band structures enable simultaneous injection of electrons and holes into an optically active material, providing a universal blueprint for light-emitting devices. Efficient modulation of the injection efficiency has previously been demonstrated by creating resonant states within the energy barrier formed by the luminescent material. Here, we present an alternative approach towards resonant tunneling conditions by fabricating tunneling junctions composed entirely from gapped materials: Cr2Ge2Te6 as electrodes, hBN as a tunneling barrier, and monolayer WSe2 as a luminescent medium. The characterization of such light-emitting tunneling structure revealed a nonmonotonous evolution of the electroluminescence intensity with the tunneling bias. The dominant role driving the characteristics of the electron tunneling was associated with the relative alignment of the density of states in Cr2Ge2Te6 electrodes. The unique device architecture introduced here presents a universal pathway towards electroluminescent devices operating at room temperature with electrically modulated emission intensity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Exploring the electron tunneling mechanisms in diverse materials systems constitutes a versatile strategy for tailoring the properties of optoelectronic devices. In this domain, bipolar vertical tunneling junctions composed of van der Waals materials with vastly different electronic band structures enable simultaneous injection of electrons and holes into an optically active material, providing a universal blueprint for light-emitting devices. Efficient modulation of the injection efficiency has previously been demonstrated by creating resonant states within the energy barrier formed by the luminescent material. Here, we present an alternative approach towards resonant tunneling conditions by fabricating tunneling junctions composed entirely from gapped materials: Cr2Ge2Te6 as electrodes, hBN as a tunneling barrier, and monolayer WSe2 as a luminescent medium. The characterization of such light-emitting tunneling structure revealed a nonmonotonous evolution of the electroluminescence intensity with the tunneling bias. The dominant role driving the characteristics of the electron tunneling was associated with the relative alignment of the density of states in Cr2Ge2Te6 electrodes. The unique device architecture introduced here presents a universal pathway towards electroluminescent devices operating at room temperature with electrically modulated emission intensity.
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Wang, Zhuyuan; Jia, Chen; Wang, Yuxiang; Yan, Xue; Yong, Ming; Low, Ze-Xian; Zeng, Xiangkang; Yang, Jindi; Zhang, Hao; Li, Xuefeng; Sun, Kaige; Tebyetekerwa, Mike; Xu, Rongming; Zhao, Wenming; Xu, Kaijie; Kang, Yuan; Strounina, Ekaterina; Andreeva, Daria V; Whittaker, Andrew K; Liu, Jefferson Zhe; Zhao, Chuan; Novoselov, Kostya S; Zhang, Xiwang Confined polymerization in nanochannels for synthesizing functional membranes Nature Synthesis, 5 , 2026, DOI: 10.1038/s44160-026-00991-z. @article{Wang2026_WOS001674879800001, title = {Confined polymerization in nanochannels for synthesizing functional membranes}, author = {Zhuyuan Wang and Chen Jia and Yuxiang Wang and Xue Yan and Ming Yong and Ze-Xian Low and Xiangkang Zeng and Jindi Yang and Hao Zhang and Xuefeng Li and Kaige Sun and Mike Tebyetekerwa and Rongming Xu and Wenming Zhao and Kaijie Xu and Yuan Kang and Ekaterina Strounina and Daria V. Andreeva and Andrew K. Whittaker and Jefferson Zhe Liu and Chuan Zhao and Kostya S. Novoselov and Xiwang Zhang}, doi = {10.1038/s44160-026-00991-z}, times_cited = {0}, issn = {2731-9697}, year = {2026}, date = {2026-02-18}, journal = {Nature Synthesis}, volume = {5}, abstract = {Synthesis of robust, functional membranes is hindered by the lack of spatial control in conventional bulk-phase reactions, which offer limited regulation over network structure and nanoscale uniformity. Here we report a nanoconfinement strategy to fabricate membranes where polymerization occurs within sub-2-nm channels that act as spatially defined reaction compartments. The nanoconfined space governs nanoscale alignment and network packing, producing high-density poly(epoxy) membranes (1.51 g cm−3), 37% denser than their non-confined analogue (1.10 g cm−3) and exceeding typical polymers. The resulting materials combine high tensile strength (119.9 MPa), flexibility (100,000 bending cycles) and broad solvent resistance, unifying properties that are difficult to achieve simultaneously. We further demonstrate that producing high-density membrane matrices facilitates selective ion transport, as shown by as-fabricated positively charged poly(ammonium) membranes, which outperform state-of-the-art counterparts in terms of mechanical strength, OH⁻ conductivity and selectivity against small neutral molecules. This work demonstrates nanomaterials as spatially confined reactors to govern polymer architecture and function, while also offering fundamental insights into structure regulation under nanoconfinement.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Synthesis of robust, functional membranes is hindered by the lack of spatial control in conventional bulk-phase reactions, which offer limited regulation over network structure and nanoscale uniformity. Here we report a nanoconfinement strategy to fabricate membranes where polymerization occurs within sub-2-nm channels that act as spatially defined reaction compartments. The nanoconfined space governs nanoscale alignment and network packing, producing high-density poly(epoxy) membranes (1.51 g cm−3), 37% denser than their non-confined analogue (1.10 g cm−3) and exceeding typical polymers. The resulting materials combine high tensile strength (119.9 MPa), flexibility (100,000 bending cycles) and broad solvent resistance, unifying properties that are difficult to achieve simultaneously. We further demonstrate that producing high-density membrane matrices facilitates selective ion transport, as shown by as-fabricated positively charged poly(ammonium) membranes, which outperform state-of-the-art counterparts in terms of mechanical strength, OH⁻ conductivity and selectivity against small neutral molecules. This work demonstrates nanomaterials as spatially confined reactors to govern polymer architecture and function, while also offering fundamental insights into structure regulation under nanoconfinement.
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Hou, Xunan; Zhu, Zichun; Wen, Yuting; Zhang, Yixin; Thedrattanawong, Chitinart; Andreeva, Daria V; Li, Jun; He, Chaobin Melt Densification Enables Fracture-Resistant Blend Hydrogels ADVANCED MATERIALS, 38 (7), 2026, DOI: 10.1002/adma.202517395. @article{WOS:001648129200001, title = {Melt Densification Enables Fracture-Resistant Blend Hydrogels}, author = {Xunan Hou and Zichun Zhu and Yuting Wen and Yixin Zhang and Chitinart Thedrattanawong and Daria V Andreeva and Jun Li and Chaobin He}, doi = {10.1002/adma.202517395}, times_cited = {0}, issn = {0935-9648}, year = {2026}, date = {2026-02-01}, journal = {ADVANCED MATERIALS}, volume = {38}, number = {7}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Hydrogels and elastomers are integral components in biomedical and electronics devices, but their toughness and crack resistance are often unsatisfactory for load-bearing applications. Synthetic polymer networks predominantly rely on solution fabrication, which compromises the ultimate mechanical properties. This work presents a universal melt crosslinking strategy, which densifies entanglements well beyond solvated conditions. When deformed, mutually entangled dissimilar chains stiffen the gels, while sparse crosslinks amplify fracture resistance. At water contents up to 83%, the resultant hydrogels demonstrate over 2 orders increase in mechanical properties, including moduli (1.3-35 MPa), toughness (0.7-24.5 kJ/m(2)), and fatigue thresholds (1.2-3.3 kJ/m(2)), tunable in a wide range beyond existing hydrogels. Furthermore, the hydrogels show high optical clarity (>96%), oxygen permeability (Dk/t > 40), and anti-fouling properties (<0.6 strategy could guide the design of tough functional soft materials in fields such as healthcare and smart electronics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hydrogels and elastomers are integral components in biomedical and electronics devices, but their toughness and crack resistance are often unsatisfactory for load-bearing applications. Synthetic polymer networks predominantly rely on solution fabrication, which compromises the ultimate mechanical properties. This work presents a universal melt crosslinking strategy, which densifies entanglements well beyond solvated conditions. When deformed, mutually entangled dissimilar chains stiffen the gels, while sparse crosslinks amplify fracture resistance. At water contents up to 83%, the resultant hydrogels demonstrate over 2 orders increase in mechanical properties, including moduli (1.3-35 MPa), toughness (0.7-24.5 kJ/m(2)), and fatigue thresholds (1.2-3.3 kJ/m(2)), tunable in a wide range beyond existing hydrogels. Furthermore, the hydrogels show high optical clarity (>96%), oxygen permeability (Dk/t > 40), and anti-fouling properties (<0.6 <mu>g cm(-2)). This generalizable strategy could guide the design of tough functional soft materials in fields such as healthcare and smart electronics.
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Pant, Prabhat; Bhatt, Diksha; Rawat, Kundan Singh; Sati, Satish Chandra; Judeh, Zaher; Mahfouz, Remi; Tayeb, Talah; Qari, Nada; Andreeva, Daria V; Novoselov, Kostya S; Sahoo, Nanda Gopal A highly efficient electrode material based on waste plastic derived rGO decorated with polypyrrole and zinc oxide nanoparticles for supercapacitor applications JOURNAL OF MATERIALS CHEMISTRY A, 14 (8), pp. 4564-4581, 2026, DOI: 10.1039/d5ta07562a. @article{WOS:001643929300001, title = {A highly efficient electrode material based on waste plastic derived rGO decorated with polypyrrole and zinc oxide nanoparticles for supercapacitor applications}, author = {Prabhat Pant and Diksha Bhatt and Kundan Singh Rawat and Satish Chandra Sati and Zaher Judeh and Remi Mahfouz and Talah Tayeb and Nada Qari and Daria V Andreeva and Kostya S Novoselov and Nanda Gopal Sahoo}, doi = {10.1039/d5ta07562a}, times_cited = {0}, issn = {2050-7488}, year = {2026}, date = {2026-02-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY A}, volume = {14}, number = {8}, pages = {4564-4581}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {The rising concern over non-biodegradable plastics, along with the global energy issue, necessitates new and sustainable solutions. One viable method is to convert plastic trash into value-added materials for electrochemical applications. In this study, we describe a two-step catalytic pyrolysis approach for producing reduced graphene oxide (rGO) from waste plastics. Additionally, we illustrate the fabrication of a waste plastic derived rGO-based ternary composite with ZnO and PPy, WP-rGO/ZnO/PPy (RPZ), which improves its electrochemical performance by providing a variety of active sites. The ternary RPZ composite's properties were evaluated by XRD, Raman spectroscopy, FT-IR, SEM, and XPS whereas the electrochemical efficiency was examined by CV, GCD, and EIS. The ternary RPZ composite electrodes exhibit a remarkable specific capacitance value of 676.4 F g-1 at 0.5 A g-1 and a strong capacitance retention of 90.6% over 5000 cycles. Moreover, the assembled symmetric energy storage device achieved an energy density of 27.23 Wh kg-1 at a high-power density of 499.97 W kg-1. Notably, LED light can be powered for up to 10 minutes using two symmetric devices that use a ternary RPZ composite as a very effective electrode material in a series configuration. This study contributes to the development of environmentally friendly energy storage systems by highlighting the potential of repurposing waste materials for advanced energy applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The rising concern over non-biodegradable plastics, along with the global energy issue, necessitates new and sustainable solutions. One viable method is to convert plastic trash into value-added materials for electrochemical applications. In this study, we describe a two-step catalytic pyrolysis approach for producing reduced graphene oxide (rGO) from waste plastics. Additionally, we illustrate the fabrication of a waste plastic derived rGO-based ternary composite with ZnO and PPy, WP-rGO/ZnO/PPy (RPZ), which improves its electrochemical performance by providing a variety of active sites. The ternary RPZ composite's properties were evaluated by XRD, Raman spectroscopy, FT-IR, SEM, and XPS whereas the electrochemical efficiency was examined by CV, GCD, and EIS. The ternary RPZ composite electrodes exhibit a remarkable specific capacitance value of 676.4 F g-1 at 0.5 A g-1 and a strong capacitance retention of 90.6% over 5000 cycles. Moreover, the assembled symmetric energy storage device achieved an energy density of 27.23 Wh kg-1 at a high-power density of 499.97 W kg-1. Notably, LED light can be powered for up to 10 minutes using two symmetric devices that use a ternary RPZ composite as a very effective electrode material in a series configuration. This study contributes to the development of environmentally friendly energy storage systems by highlighting the potential of repurposing waste materials for advanced energy applications.
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Zhang, Hongji; Grebenko, Artem K; Litvinov, Dmitrii; Zheng, Wenwen; Iakoubovskii, Konstantin V; Grebenchuk, Sergey Y; Makarova, Anna; Fedorov, Alexander; Starkov, Andrei; Orofeo, Carlo M; Vyalikh, Denis V; Lanza, Mario; Koperski, Maciej; Novoselov, Kostya S; Toh, Chee-tat; Ozyilmaz, Barbaros Breaking the 2-nm Barrier in Hard Disk Drives Using Monolayer Amorphous Carbon Overcoats ADVANCED MATERIALS, 2026, DOI: 10.1002/adma.202519149. @article{WOS:001680918000001, title = {Breaking the 2-nm Barrier in Hard Disk Drives Using Monolayer Amorphous Carbon Overcoats}, author = {Hongji Zhang and Artem K Grebenko and Dmitrii Litvinov and Wenwen Zheng and Konstantin V Iakoubovskii and Sergey Y Grebenchuk and Anna Makarova and Alexander Fedorov and Andrei Starkov and Carlo M Orofeo and Denis V Vyalikh and Mario Lanza and Maciej Koperski and Kostya S Novoselov and Chee-tat Toh and Barbaros Ozyilmaz}, doi = {10.1002/adma.202519149}, times_cited = {0}, issn = {0935-9648}, year = {2026}, date = {2026-02-01}, journal = {ADVANCED MATERIALS}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {The rapid growth of artificial intelligence (AI) has increased the demand for large-scale data storage, making hard disk drives (HDDs) indispensable in data centers due to their cost-effectiveness and stability. To support AI-driven data requirements, increasing the areal storage density is critical. However, this metric is increasingly constrained by the carbon overcoat (COC), the essential protective layer for magnetic media. Traditional diamond-like carbon (DLC) can no longer fulfill the stringent demands for ultrathin coatings and high thermal stability required by next-generation technologies like Heat-Assisted Magnetic Recording (HAMR) and bit-patterned media. Here, we introduce monolayer amorphous carbon (MAC) as a superior alternative. MAC is directly grown on the heterogeneous (Fe, Pt, SiO2) HDD surface at low temperatures (similar to 300 degrees C), achieving an uniform 0.8 nm thickness across 2.5-inch disks. Despite its atomic thickness, MAC demonstrates high corrosion resistance and low roughness comparable to commercial 2.5 nm COCs. Its fully amorphous, sp2-hybridized structure ensures excellent thermal stability under HAMR-like conditions (similar to 450 degrees C) and a low friction coefficient, enabling potential lubricant-free operation. Replacing traditional COCs with MAC facilitates the development of HDD media capable of achieving 10 Tb/in2, addressing the urgent storage demands of the digital era.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The rapid growth of artificial intelligence (AI) has increased the demand for large-scale data storage, making hard disk drives (HDDs) indispensable in data centers due to their cost-effectiveness and stability. To support AI-driven data requirements, increasing the areal storage density is critical. However, this metric is increasingly constrained by the carbon overcoat (COC), the essential protective layer for magnetic media. Traditional diamond-like carbon (DLC) can no longer fulfill the stringent demands for ultrathin coatings and high thermal stability required by next-generation technologies like Heat-Assisted Magnetic Recording (HAMR) and bit-patterned media. Here, we introduce monolayer amorphous carbon (MAC) as a superior alternative. MAC is directly grown on the heterogeneous (Fe, Pt, SiO2) HDD surface at low temperatures (similar to 300 degrees C), achieving an uniform 0.8 nm thickness across 2.5-inch disks. Despite its atomic thickness, MAC demonstrates high corrosion resistance and low roughness comparable to commercial 2.5 nm COCs. Its fully amorphous, sp2-hybridized structure ensures excellent thermal stability under HAMR-like conditions (similar to 450 degrees C) and a low friction coefficient, enabling potential lubricant-free operation. Replacing traditional COCs with MAC facilitates the development of HDD media capable of achieving 10 Tb/in2, addressing the urgent storage demands of the digital era.
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Chen, Xuemin; Zhong, Qi-Zhi; Qian, Zeyu; Nguyen, Lam Bang Thanh; Chen, Jaslyn Ru Ting; Tan, Emily Xi; Wang, Keteng; Song, Fan; Richardson, Joseph J; Lv, Yan; Ling, Xing Yi; Liu, Tianxi In situ photo-regenerative phenolic interface for continuous precious metal recovery NATURE WATER, 2026, DOI: 10.1038/s44221-026-00591-3. @article{WOS:001682467700001, title = {In situ photo-regenerative phenolic interface for continuous precious metal recovery}, author = {Xuemin Chen and Qi-Zhi Zhong and Zeyu Qian and Lam Bang Thanh Nguyen and Jaslyn Ru Ting Chen and Emily Xi Tan and Keteng Wang and Fan Song and Joseph J Richardson and Yan Lv and Xing Yi Ling and Tianxi Liu}, doi = {10.1038/s44221-026-00591-3}, times_cited = {0}, year = {2026}, date = {2026-02-01}, journal = {NATURE WATER}, publisher = {SPRINGERNATURE}, address = {CAMPUS, 4 CRINAN ST, LONDON, N1 9XW, ENGLAND}, abstract = {Water contamination and the resource scarcity of precious metals pose pressing environmental challenges, making sustainable recovery from secondary sources an attractive alternative to conventional mining. Yet, progress has been hindered by low adsorption capacities and the irreversible loss of active binding sites. Here we introduce a photochemical regeneration strategy that embeds a phenol-quinone redox cycle into a photoactive nanocarbon aerogel, enabling continuous recovery through light-driven electron transfer and proton-coupled redox cycling. This design repeatedly captures and releases precious metals, achieving ultrahigh adsorption (similar to 15,925.5 mg g(-1) for Au), greatly extended lifespan (>250 h) and broad applicability across diverse metals (Au, Ag, Pt and Pd) and concentrations (0.6 ppb to 1,000 ppm). Compared with state-of-the-art materials, it achieves over threefold higher capacity and a tenfold longer operational lifetime, while simultaneously reducing electricity and reagent consumption by 88.4% and 97.7%, respectively. Demonstrations in industrial waste (for example, central processing unit leachates) and natural seawater validate this approach as a practical, scalable and sustainable solution for precious metal recovery in real-world circular economy applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Water contamination and the resource scarcity of precious metals pose pressing environmental challenges, making sustainable recovery from secondary sources an attractive alternative to conventional mining. Yet, progress has been hindered by low adsorption capacities and the irreversible loss of active binding sites. Here we introduce a photochemical regeneration strategy that embeds a phenol-quinone redox cycle into a photoactive nanocarbon aerogel, enabling continuous recovery through light-driven electron transfer and proton-coupled redox cycling. This design repeatedly captures and releases precious metals, achieving ultrahigh adsorption (similar to 15,925.5 mg g(-1) for Au), greatly extended lifespan (>250 h) and broad applicability across diverse metals (Au, Ag, Pt and Pd) and concentrations (0.6 ppb to 1,000 ppm). Compared with state-of-the-art materials, it achieves over threefold higher capacity and a tenfold longer operational lifetime, while simultaneously reducing electricity and reagent consumption by 88.4% and 97.7%, respectively. Demonstrations in industrial waste (for example, central processing unit leachates) and natural seawater validate this approach as a practical, scalable and sustainable solution for precious metal recovery in real-world circular economy applications.
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Moon, Ji Yun; Bae, Sanggeun; Ryu, Jeehoon; Kim, Seung Il; Han, Sangmoon; Kim, Justin S; Choi, Jonggyu; Kim, Seungsoo; Lee, Joo Hong; Choi, Seung Gu; Liu, Ting Ran; Ahn, Soyeong; Seo, Jihyung; Choi, Jun Hui; Kwun, Hyung Jun; Shao, Yu Tsun; Kim, Hyeon Don; Park, Jin Hong; Lee, Jin Wook; Park, Ji Won; Lee, Jae Hyun; Ahn, Jong Hyun; Bae, Sang Hoon Crack-Free Transfer of Wafer-Scale Freestanding Single-Crystalline Nanomembranes Enabled by Elastically Graded Polymer ADVANCED MATERIALS, 38 (1), 2026, DOI: 10.1002/adma.202513080. @article{WOS:001569522600001, title = {Crack-Free Transfer of Wafer-Scale Freestanding Single-Crystalline Nanomembranes Enabled by Elastically Graded Polymer}, author = {Ji Yun Moon and Sanggeun Bae and Jeehoon Ryu and Seung Il Kim and Sangmoon Han and Justin S Kim and Jonggyu Choi and Seungsoo Kim and Joo Hong Lee and Seung Gu Choi and Ting Ran Liu and Soyeong Ahn and Jihyung Seo and Jun Hui Choi and Hyung Jun Kwun and Yu Tsun Shao and Hyeon Don Kim and Jin Hong Park and Jin Wook Lee and Ji Won Park and Jae Hyun Lee and Jong Hyun Ahn and Sang Hoon Bae}, doi = {10.1002/adma.202513080}, times_cited = {1}, issn = {0935-9648}, year = {2026}, date = {2026-01-01}, journal = {ADVANCED MATERIALS}, volume = {38}, number = {1}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Freestanding single-crystalline nanomembranes have gained increasing attention as promising platforms for both fundamental research and advanced electronic applications. However, internal stress gradients arising from epitaxial strain within the oxide membranes often result in high crack density during fabrication, leading to unsatisfactory yield and limited reliability. Here, an elastically graded polymer (EGP) support that enables wafer-scale crack-free transfer of single-crystalline oxide membranes are developed. The engineered elastic gradient within the EGP accommodates the internal strain of the oxide membrane, effectively minimizing crack formation during lift-off. Notably, this ability to spatially control the interfacial stiffness between the polymer and the oxide film enables crack suppression under both tensile and compressive strain. This approach provides a robust and scalable route to producing high-quality freestanding oxide membranes, paving the way not only for their integration into novel device architecture but also opening new avenues for scientific exploration of functional systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Freestanding single-crystalline nanomembranes have gained increasing attention as promising platforms for both fundamental research and advanced electronic applications. However, internal stress gradients arising from epitaxial strain within the oxide membranes often result in high crack density during fabrication, leading to unsatisfactory yield and limited reliability. Here, an elastically graded polymer (EGP) support that enables wafer-scale crack-free transfer of single-crystalline oxide membranes are developed. The engineered elastic gradient within the EGP accommodates the internal strain of the oxide membrane, effectively minimizing crack formation during lift-off. Notably, this ability to spatially control the interfacial stiffness between the polymer and the oxide film enables crack suppression under both tensile and compressive strain. This approach provides a robust and scalable route to producing high-quality freestanding oxide membranes, paving the way not only for their integration into novel device architecture but also opening new avenues for scientific exploration of functional systems.
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Ponnusamy, Krishna Moorthy; Bong, Jungwoo; Lee, Hyunjin; Choi, Jun-Hui; Pandit, Bhishma; Ghods, Soheil; Durairaj, Santhosh; Park, Jong Bae; Lee, Yoon Kyeung; Lee, Taehun; Lee, Jae-Hyun; Jang, Hyeon-Sik; Chandramohan, S; Heo, Keun Promoter-Free Synthesis of Wafer-Scale Monolayer MoS2 for Visible to Near-Infrared Photodetection ACS APPLIED MATERIALS & INTERFACES, 18 (1), pp. 1995-2008, 2026, DOI: 10.1021/acsami.5c19820. @article{WOS:001647974100001, title = {Promoter-Free Synthesis of Wafer-Scale Monolayer MoS2 for Visible to Near-Infrared Photodetection}, author = {Krishna Moorthy Ponnusamy and Jungwoo Bong and Hyunjin Lee and Jun-Hui Choi and Bhishma Pandit and Soheil Ghods and Santhosh Durairaj and Jong Bae Park and Yoon Kyeung Lee and Taehun Lee and Jae-Hyun Lee and Hyeon-Sik Jang and S Chandramohan and Keun Heo}, doi = {10.1021/acsami.5c19820}, times_cited = {0}, issn = {1944-8244}, year = {2026}, date = {2026-01-01}, journal = {ACS APPLIED MATERIALS & INTERFACES}, volume = {18}, number = {1}, pages = {1995-2008}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {Atomically thin two-dimensional molybdenum disulfide (MoS2) has emerged as a promising semiconductor for next-generation optoelectronic applications. While chemical vapor deposition (CVD) enables large-area monolayer growth, achieving high-quality and reproducible synthesis without catalysts or promoters remains a critical challenge as common additives such as NaCl or oxygen can undesirably modify the material properties. In this study, we report the successful batch production of high-quality monolayer MoS2 films on 2-in. sapphire wafers using a promoter-free CVD approach. By systematically optimizing the growth parameters and precisely controlling the sulfur-to-MoO3 ratio, particularly the amount of sulfur vapor supplied, we realized additive-free synthesis on a wafer-scale by using a dual-source delivery system with an inner quartz tube configuration. Thermodynamic modeling confirms that separating the MoO3 and sulfur pathways improves vapor stability, suppresses intermediate phases, and ensures a controlled synthesis. Microscopy, spectroscopy, and electrical measurements confirm the synthesis of highly crystalline monolayer MoS2 with excellent wafer-scale uniformity and reproducibility. Photodetector arrays fabricated from the films exhibited outstanding performance: statistical analysis of 63 devices (within the 10-90% performance range) demonstrated a responsivity of similar to 5.72 A/W (+/- 2.9 A/W), a superior detectivity of similar to 1.53 x 10(12) Jones, and an external quantum efficiency of similar to 1687% at 450 nm under ambient conditions. Additionally, the devices also showed excellent long-term operational stability. Our method offers a cost-effective, additive-free, and scalable route to produce high-quality MoS2 toward future optoelectronics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Atomically thin two-dimensional molybdenum disulfide (MoS2) has emerged as a promising semiconductor for next-generation optoelectronic applications. While chemical vapor deposition (CVD) enables large-area monolayer growth, achieving high-quality and reproducible synthesis without catalysts or promoters remains a critical challenge as common additives such as NaCl or oxygen can undesirably modify the material properties. In this study, we report the successful batch production of high-quality monolayer MoS2 films on 2-in. sapphire wafers using a promoter-free CVD approach. By systematically optimizing the growth parameters and precisely controlling the sulfur-to-MoO3 ratio, particularly the amount of sulfur vapor supplied, we realized additive-free synthesis on a wafer-scale by using a dual-source delivery system with an inner quartz tube configuration. Thermodynamic modeling confirms that separating the MoO3 and sulfur pathways improves vapor stability, suppresses intermediate phases, and ensures a controlled synthesis. Microscopy, spectroscopy, and electrical measurements confirm the synthesis of highly crystalline monolayer MoS2 with excellent wafer-scale uniformity and reproducibility. Photodetector arrays fabricated from the films exhibited outstanding performance: statistical analysis of 63 devices (within the 10-90% performance range) demonstrated a responsivity of similar to 5.72 A/W (+/- 2.9 A/W), a superior detectivity of similar to 1.53 x 10(12) Jones, and an external quantum efficiency of similar to 1687% at 450 nm under ambient conditions. Additionally, the devices also showed excellent long-term operational stability. Our method offers a cost-effective, additive-free, and scalable route to produce high-quality MoS2 toward future optoelectronics.
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Hardian, Rifan; Vovusha, Hakkim; Yuan, Yue; Shi, Changxia; Chen, Eugene Y -X; Lanza, Mario; Szekely, Gyorgy Structural and Mechanical Dynamics of Polymer Membranes Across Multilength Scales ADVANCED SCIENCE, 2026, DOI: 10.1002/advs.202521391. @article{WOS:001664835100001, title = {Structural and Mechanical Dynamics of Polymer Membranes Across Multilength Scales}, author = {Rifan Hardian and Hakkim Vovusha and Yue Yuan and Changxia Shi and Eugene Y -X Chen and Mario Lanza and Gyorgy Szekely}, doi = {10.1002/advs.202521391}, times_cited = {0}, year = {2026}, date = {2026-01-01}, journal = {ADVANCED SCIENCE}, publisher = {WILEY}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {Understanding the mechanical and structural evolution of polymer membranes under heat and strain is important for many applications. Conventional techniques, such as dynamic mechanical analysis provide bulk mechanical information but lack the spatial resolution to capture localized variations. Similarly, X-ray diffraction spectroscopy effectively probes long-range order but has limited capability in analyzing amorphous polymer structures. Herein, we reveal the importance of mechanical and structural analyses across multilength scales. We unveiled the opposite trend in surface-to-bulk mechanical behavior of polymer membranes, necessitating the investigation of both regions to fully capture their functional behavior. We mapped nanoscale mechanical inhomogeneities across membrane surfaces with in situ atomic force microscopy quantitative nanomechanics. Further, we uncovered structural irregularities across both short- and long-range order using in situ small- and wide-angle scattering spectroscopies. We investigate key structural parameters and describe density variations in amorphous domains. Molecular dynamics simulations corroborate with the observed structural and mechanical properties at the molecular level. Our multilength-scale characterization strategy provides a robust framework for elucidating structure-property relationships from macroscopic to molecular levels. The approach is generalizable to other systems such as films, fibers, and two-dimensional materials, enabling new insights into their dynamic properties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Understanding the mechanical and structural evolution of polymer membranes under heat and strain is important for many applications. Conventional techniques, such as dynamic mechanical analysis provide bulk mechanical information but lack the spatial resolution to capture localized variations. Similarly, X-ray diffraction spectroscopy effectively probes long-range order but has limited capability in analyzing amorphous polymer structures. Herein, we reveal the importance of mechanical and structural analyses across multilength scales. We unveiled the opposite trend in surface-to-bulk mechanical behavior of polymer membranes, necessitating the investigation of both regions to fully capture their functional behavior. We mapped nanoscale mechanical inhomogeneities across membrane surfaces with in situ atomic force microscopy quantitative nanomechanics. Further, we uncovered structural irregularities across both short- and long-range order using in situ small- and wide-angle scattering spectroscopies. We investigate key structural parameters and describe density variations in amorphous domains. Molecular dynamics simulations corroborate with the observed structural and mechanical properties at the molecular level. Our multilength-scale characterization strategy provides a robust framework for elucidating structure-property relationships from macroscopic to molecular levels. The approach is generalizable to other systems such as films, fibers, and two-dimensional materials, enabling new insights into their dynamic properties.
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Lee, Taelim; Bong, Jungwoo; Lee, Hyunjin; Lee, Ho-Sung; Jang, Hyeon-Sik; Kim, Hee-Tae; Lee, Jae-Hyun; Cho, Byung Jin; Choi, Yeon-Ho; Bae, Hagyoul; Moon, Taehwan; Heo, Keun Enhanced Dielectric Constant by Al Gradient Doping on Atomic-Layer-Deposited HfO2-Based Metal-Insulator-Metal Capacitor ADVANCED ELECTRONIC MATERIALS, 2026, DOI: 10.1002/aelm.202500679. @article{WOS:001662227700001, title = {Enhanced Dielectric Constant by Al Gradient Doping on Atomic-Layer-Deposited HfO2-Based Metal-Insulator-Metal Capacitor}, author = {Taelim Lee and Jungwoo Bong and Hyunjin Lee and Ho-Sung Lee and Hyeon-Sik Jang and Hee-Tae Kim and Jae-Hyun Lee and Byung Jin Cho and Yeon-Ho Choi and Hagyoul Bae and Taehwan Moon and Keun Heo}, doi = {10.1002/aelm.202500679}, times_cited = {0}, issn = {2199-160X}, year = {2026}, date = {2026-01-01}, journal = {ADVANCED ELECTRONIC MATERIALS}, publisher = {WILEY}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {As industries increasingly demand larger data capacities and faster processing, enhancing the capacitance of metal-insulator-metal (MIM) capacitors becomes crucial. This study investigates the effect of aluminum (Al) gradient doping on the dielectric constant of HfO2-based MIM capacitors. Compared with conventional uniform doping, gradient doping more effectively accelerates the transition of HfO2 to its high-k tetragonal phase, leading to higher capacitance. The study also explores factors such as the annealing temperature and atomic layer deposition conditions to optimize the high-k performance. Capacitors were fabricated and tested with gradient and uniform doping under 400 degrees C, 500 degrees C, and 600 degrees C annealing conditions. Gradient doping significantly reduces the leakage current by an order of magnitude. The uniformly doped capacitors exhibit a dielectric constant of similar to 44.7 and an equivalent oxide thickness (EOT) of 0.96 nm, whereas those with gradient doping achieve a dielectric constant of similar to 60.7, which is the highest k-value of HfO2 reported to date, and an EOT of 0.71 nm, representing a 35.8% improvement in dielectric constant and a 0.25 nm reduction in EOT. These findings highlight the potential of gradient doping to enhance MIM capacitor performance for high-capacitance applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } As industries increasingly demand larger data capacities and faster processing, enhancing the capacitance of metal-insulator-metal (MIM) capacitors becomes crucial. This study investigates the effect of aluminum (Al) gradient doping on the dielectric constant of HfO2-based MIM capacitors. Compared with conventional uniform doping, gradient doping more effectively accelerates the transition of HfO2 to its high-k tetragonal phase, leading to higher capacitance. The study also explores factors such as the annealing temperature and atomic layer deposition conditions to optimize the high-k performance. Capacitors were fabricated and tested with gradient and uniform doping under 400 degrees C, 500 degrees C, and 600 degrees C annealing conditions. Gradient doping significantly reduces the leakage current by an order of magnitude. The uniformly doped capacitors exhibit a dielectric constant of similar to 44.7 and an equivalent oxide thickness (EOT) of 0.96 nm, whereas those with gradient doping achieve a dielectric constant of similar to 60.7, which is the highest k-value of HfO2 reported to date, and an EOT of 0.71 nm, representing a 35.8% improvement in dielectric constant and a 0.25 nm reduction in EOT. These findings highlight the potential of gradient doping to enhance MIM capacitor performance for high-capacitance applications.
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Jana, Dipankar; Acharya, Swagata; Orlita, Milan; Faugeras, Clement; Pashov, Dimitar; Schilfgaarde, Mark Van; Potemski, Marek; Koperski, Maciej Deconstruction of the Anisotropic Magnetic Interactions from Spin-Entangled Optical Excitations in van der Waals Antiferromagnets ADVANCED SCIENCE, 13 (2), 2026, DOI: 10.1002/advs.202505834. @article{WOS:001610214800001, title = {Deconstruction of the Anisotropic Magnetic Interactions from Spin-Entangled Optical Excitations in van der Waals Antiferromagnets}, author = {Dipankar Jana and Swagata Acharya and Milan Orlita and Clement Faugeras and Dimitar Pashov and Mark Van Schilfgaarde and Marek Potemski and Maciej Koperski}, doi = {10.1002/advs.202505834}, times_cited = {1}, year = {2026}, date = {2026-01-01}, journal = {ADVANCED SCIENCE}, volume = {13}, number = {2}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Magneto-optical excitations in antiferromagnetic d systems can originate from a multiplicity of light-spin and spin-spin interactions, as the light and spin degrees of freedom can be entangled. This is exemplified in van der Waals systems with attendant strong anisotropy between in-plane and out-of-plane directions, such as and films studied here. The rich interplay between the magnetic ordering and sub-bandgap optical transitions poses a challenge to resolve the mechanisms driving spin-entangled optical transitions, as well as the single-particle bandgap itself. Here, a high-fidelity ab initio theory is applied to find a realistic estimation of the bandgap by elucidating the atom- and orbital-resolved contributions to the fundamental sub-bands. It is further demonstrated that the spin-entangled excitations, observable as photoluminescence and absorption resonances, originate from an on-site spin-flip transition confined to a magnetic atom (Mn or Ni). The evolution of the spin-flip transition in a magnetic field is used to deduce the effective exchange coupling and anisotropy constants.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Magneto-optical excitations in antiferromagnetic d systems can originate from a multiplicity of light-spin and spin-spin interactions, as the light and spin degrees of freedom can be entangled. This is exemplified in van der Waals systems with attendant strong anisotropy between in-plane and out-of-plane directions, such as and films studied here. The rich interplay between the magnetic ordering and sub-bandgap optical transitions poses a challenge to resolve the mechanisms driving spin-entangled optical transitions, as well as the single-particle bandgap itself. Here, a high-fidelity ab initio theory is applied to find a realistic estimation of the bandgap by elucidating the atom- and orbital-resolved contributions to the fundamental sub-bands. It is further demonstrated that the spin-entangled excitations, observable as photoluminescence and absorption resonances, originate from an on-site spin-flip transition confined to a magnetic atom (Mn or Ni). The evolution of the spin-flip transition in a magnetic field is used to deduce the effective exchange coupling and anisotropy constants.
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Gardella, Matteo; Massetti, Chiara; Cataldo, Alessandro; Tummala, Pinakapani; Lamperti, Alessio; Grazianetti, Carlo; Martella, Christian; Molle, Alessandro Substrate-Versatile and Stress-Free Tellurization of PtTe2 Films PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS, 20 (1, SI), 2026, DOI: 10.1002/pssr.202500305. @article{WOS:001589410700001, title = {Substrate-Versatile and Stress-Free Tellurization of PtTe2 Films}, author = {Matteo Gardella and Chiara Massetti and Alessandro Cataldo and Pinakapani Tummala and Alessio Lamperti and Carlo Grazianetti and Christian Martella and Alessandro Molle}, doi = {10.1002/pssr.202500305}, times_cited = {0}, issn = {1862-6254}, year = {2026}, date = {2026-01-01}, journal = {PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS}, volume = {20}, number = {1, SI}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Platinum ditelluride (PtTe2) is a type-II Dirac semimetal featuring tilted cones in its electronic band structure, which leads to intriguing electronic and optical topological properties. Here, a large area growth process is presented for the synthesis of PtTe2 films with nanoscale thickness by sputtering deposition of a Pt precursor layer and subsequent tellurization at 450 degrees C. Although the Pt deposition step does not pose stringent limitation on the substrate choice, it is demonstrated that the heating rate during the tellurization step can induce a significant thermal-induced strain when the process is extended from silicon dielectric transparent silica substrates, leading to macroscopic wrinkling of the PtTe2 film. Thus, a slower tellurization process is optimized, successfully resulting in stress-free growth even on dielectric substrates. Additionally, the same new process repeated on silicon substrates shows a threefold enhanced minimum grain size compared to the original process. These accomplishments, combined with the scalability of the growth technique and the deterministic material patterning achieved by optical lithography, are crucial for a facile integration of PtTe2 in any kind of device.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Platinum ditelluride (PtTe2) is a type-II Dirac semimetal featuring tilted cones in its electronic band structure, which leads to intriguing electronic and optical topological properties. Here, a large area growth process is presented for the synthesis of PtTe2 films with nanoscale thickness by sputtering deposition of a Pt precursor layer and subsequent tellurization at 450 degrees C. Although the Pt deposition step does not pose stringent limitation on the substrate choice, it is demonstrated that the heating rate during the tellurization step can induce a significant thermal-induced strain when the process is extended from silicon dielectric transparent silica substrates, leading to macroscopic wrinkling of the PtTe2 film. Thus, a slower tellurization process is optimized, successfully resulting in stress-free growth even on dielectric substrates. Additionally, the same new process repeated on silicon substrates shows a threefold enhanced minimum grain size compared to the original process. These accomplishments, combined with the scalability of the growth technique and the deterministic material patterning achieved by optical lithography, are crucial for a facile integration of PtTe2 in any kind of device.
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Lopez-Garcia, Fernando; Freixas, Victor M; Mikhailovsky, Alexander; Bazan, Guillermo C; Tretiak, Sergei Theoretical and Experimental Assessment of the Absorption and Dual Emission of Benzobisthiadiazole Conjugated Oligoelectrolyte Probes JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 17 (1), pp. 119-126, 2026, DOI: 10.1021/acs.jpclett.5c03378. @article{WOS:001649798600001, title = {Theoretical and Experimental Assessment of the Absorption and Dual Emission of Benzobisthiadiazole Conjugated Oligoelectrolyte Probes}, author = {Fernando Lopez-Garcia and Victor M Freixas and Alexander Mikhailovsky and Guillermo C Bazan and Sergei Tretiak}, doi = {10.1021/acs.jpclett.5c03378}, times_cited = {0}, issn = {1948-7185}, year = {2026}, date = {2026-01-01}, journal = {JOURNAL OF PHYSICAL CHEMISTRY LETTERS}, volume = {17}, number = {1}, pages = {119-126}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {The conjugated oligoelectrolyte COE-BBT and its neutral form, BBT-Br, are probes based on benzobisthiadiazole and thiophene-stilbene units with near-infrared emissions. Upon photoexcitation, these compounds exhibit a second emission band, suggesting anti-Kasha character of their fluorescence. Here, we disclose theoretical evidence in support of the non-Kasha behavior of BBT probes. We employ time-dependent density functional theory (TD-DFT) and nonadiabatic molecular dynamics to simulate and analyze absorption and emission phenomena, providing a comprehensive understanding of the electronic and structural excited-state behavior and photophysical properties. In particular, our results support the presence of two distinct excited states from where emission is possible.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The conjugated oligoelectrolyte COE-BBT and its neutral form, BBT-Br, are probes based on benzobisthiadiazole and thiophene-stilbene units with near-infrared emissions. Upon photoexcitation, these compounds exhibit a second emission band, suggesting anti-Kasha character of their fluorescence. Here, we disclose theoretical evidence in support of the non-Kasha behavior of BBT probes. We employ time-dependent density functional theory (TD-DFT) and nonadiabatic molecular dynamics to simulate and analyze absorption and emission phenomena, providing a comprehensive understanding of the electronic and structural excited-state behavior and photophysical properties. In particular, our results support the presence of two distinct excited states from where emission is possible.
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