Article
Nanoscience & Nanotechnology
Alexander K. Fedotov, Uladzislaw E. Gumiennik, Julia A. Fedotova, Janusz Przewoznik, Czeslaw Kapusta
Summary: The study conducted an improved analysis of carrier transport in single-layer graphene and hybrid structures, showing the coexistence of negative and positive contributions in magnetoresistive effect. Various models were used to analyze the dependences on temperature and magnetic field, providing insights into the behavior of electrical resistance in the structures.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2024)
Article
Materials Science, Multidisciplinary
Qianwen Wang, Tenghua Gao, Takashi Harumoto, Kazuya Ando, Yoshio Nakamura, Ji Shi
Summary: Enhanced linear positive magnetoresistance of graphene is achieved at room temperature by depositing Co particles on the surface, which introduces strong inhomogeneity. The interfacial hybridization between graphene and Co further enhances spatial fluctuation of carrier density and mobility, leading to a higher PMR that is useful for magnetic sensing at room temperature.
Article
Materials Science, Multidisciplinary
Ke Wang, T. A. Sedrakyan
Summary: Perpendicular magnetic field introduces an anomalous interaction correction to the static conductivity of doped graphene, leading to a proportional relationship between magnetoresistance and inverse temperature. This behavior originates from field-induced breaking of symmetry.
Article
Construction & Building Technology
Wei He, Jiangwei Liang, Jihang Xu, Zhinan Jiao, Ning Cui, Junshuang Zhou
Summary: This study systematically investigated the effects of few-layer graphene (FLG) on the mechanical and electrical properties of cement mortar. The results showed that the addition of FLG improved the compressive strength, flexural strength, and conductivity of mortar. Additionally, FLG promoted a better connection between cement paste and aggregate, resulting in a denser mortar structure.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Chemistry, Physical
Hanane Boumeriame, Bruno F. Machado, Nuno M. M. Moura, Philippe Serp, Luisa Andrade, Tania Lopes, Adelio Mendes, Tarik Chafik, Eliana S. Da Silva, Joaquim L. Faria
Summary: In this study, few-layer graphene prepared by catalytic chemical vapour deposition and bulk graphitic carbon nitride were assembled into novel heterostructures, showing enhanced photocatalytic activity for H-2 generation. The best performing composite exhibited 4 times higher H-2 generation rate than pure GCN with high stability after four successive cycles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Physics, Multidisciplinary
N. Arabchigavkani, R. Somphonsane, H. Ramamoorthy, G. He, J. Nathawat, S. Yin, B. Barut, K. He, M. D. Randle, R. Dixit, K. Sakanashi, N. Aoki, K. Zhang, L. Wang, W-N Mei, P. A. Dowben, J. Fransson, J. P. Bird
Summary: Mesoscopic conductance fluctuations are a common feature in small conductors, but this study reveals a breakdown of universality due to the interplay of local and remote phenomena in transport. The experiments demonstrate that remote factors can significantly impact conductivity in phase-coherent conductors, leading to giant conductance fluctuations exceeding theoretical predictions.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Wei-Chen Chen, Chiashain Chuang, Tian-Hsin Wang, Ching-Chen Yeh, Sheng-Zong Chen, Kohei Sakanashi, Michio Kida, Li-Hung Lin, Po-Han Lee, Po-Chen Wu, Sheng-Wen Wang, Kenji Watanabe, Takashi Taniguchi, Ya-Ping Hsieh, Nobuyuki Aoki, Chi-Te Liang
Summary: In this study, the fabrication and measurements of a single-layer SnSe2/CVD graphene/h-BN field-effect device were reported. The coherent magnetotransport properties of this hybrid system were systematically studied, revealing the potential of quantum coherent effect and its applications in fields such as thermoelectricity, flexible electronics, and quantum coherent sensing.
Article
Chemistry, Physical
Pingping Zhuang, Jing Liu, Junjie Huang, Chao Dou, Weiwei Cai, Weiyi Lin
Summary: This study investigates the charge distribution between layers in van der Waals stacked crystals using carbon isotope-labeled few-layer graphene. The electrical transfer characteristics of graphene field-effect transistors are used to calibrate the correspondence between Fermi level and G-phonon frequency. The results reveal that the charge concentration in both top and bottom layers of few-layer graphene is close and does not follow the exponential decay law. Additionally, each additional layer of graphene reduces the charge exchange at the graphene/dopant interface. These findings have important implications for electronic applications based on two-dimensional materials and provide a framework for further exploring the properties of other two-dimensional systems.
Article
Engineering, Environmental
Libo Wang, Haiyan Tan, Liuyang Zhang, Bei Cheng, Jiaguo Yu
Summary: In this study, a composite material was developed by in-situ deposition of few-layer graphene on the surface of ZnO, leading to enhanced photocatalytic CO2 reduction performance. The improvement was attributed to the intimate interfacial contact and Schottky junction between ZnO and graphene, as well as the photothermal effect of graphene and pi-pi conjugation interaction with CO2 molecules. This work not only provides a feasible method for the in-situ growth of graphene, but also presents an efficient photocatalyst for CO2 reduction.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
A. Mohapatra, S. Das, K. Majumdar, M. S. Ramachandra Rao, Manu Jaiswal
Summary: Wrinkles significantly influence the thermal transport in vertical assemblies of few-layer graphene crystallites. While the presence of wrinkles enhances the thermal conductivity locally, it also leads to a significant decrease in the total interface conductance compared to unwrinkled regions. This study highlights the strong impact of wrinkles on the thermal properties of layered 2D materials.
NANOSCALE ADVANCES
(2021)
Article
Engineering, Environmental
Kun Lu, Qingyuan Hu, Li Zhai, Zhiyu Zhu, Yunsong Xu, Zhaohui Ding, Hang Zeng, Shipeng Dong, Shixiang Gao, Liang Mao
Summary: This study reveals the biological fate of graphene in algae and its potential biological effects, which is important for assessing the environmental risks of graphene.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Hamza El Marouazi, Pablo Jimenez-Calvo, Edouard Breniaux, Christophe Colbeau-Justin, Izabela Janowska, Valerie Keller
Summary: The study investigated the characteristics of few layer graphene/TiO2 photocatalytic composites with loadings ranging from 0.5 to 11 wt % and their impact on hydrogen production from methanol. It was found that the composites with 0.5 and 1.0 wt % FLG/TiO2 exhibited the best activity.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Physics, Applied
Chiranjit Karmakar, R. K. Kaneriya, Megha Malasi, Shivam Rathod, Devendra Kumar, Sujay Chakravarty, R. B. Upadhyay, Punam Kumar, A. N. Bhattacharya, U. S. Joshi
Summary: In this study, weak localization and negative magnetoresistance behavior are observed in a quaternary GaN two-dimensional electron gas (2DEG) system. The dephasing time and temperature dependency of the dephasing rate are determined using a Hikami-Larkin-Nagaoka model. Shubnikov-de Haas quantum oscillation induced by 2DEG is also observed.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Chuan-Xin Cui, Jin-Wu Jiang
Summary: In this study, molecular dynamics simulations were used to investigate the effect of the layer number on gas permeation through a nanopore within few-layer graphene. The results showed that the permeation constant decreases with increasing layer number. By considering the nanoscale effect from the surface morphology of the nanopore, the macroscopic model can accurately describe the layer number dependence for the gas permeation constant.
Article
Chemistry, Multidisciplinary
Guilin Feng, Nozomu Suzuki, Qiang Zhang, Jiangtao Li, Tomoko Inose, Farsai Taemaitree, K. M. Muhammed Shameem, Shuichi Toyouchi, Yasuhiko Fujita, Kenji Hirai, Hiroshi Uji-i
Summary: In this study, we report the use of acetic acid as a new potential candidate for covalently patterned graphene in graphene-enhanced Raman scattering (GERS). Rhodamine 6G molecules in direct contact with the covalently modified region exhibit a tremendous enhancement (approximately 25 times) compared to the pristine region at 532 nm excitation. The influence of layer thickness, excitation wavelength, and covalently attached groups on the GERS enhancement is discussed.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Biao Wu, Haihong Zheng, Shaofei Li, Chang -Tian Wang, Junnan Ding, Jun He, Zongwen Liu, Jian-Tao Wang, Yanping Liu
Summary: The recent discovery of various moire-related properties in twisted vertical stacking structures has attracted significant attention, particularly in transition metal dichalcogenide heterostructures. This study presents the observation of moire excitons in homostructures with different layer-coupling interactions, and the results show that reducing the number of underlying layers increases the moire potential. The effects of temperature, laser power, and valley polarization on moire excitons were also investigated, providing insights into their spectral features. These findings pave the way for the exploration of quantum phenomena and related applications in quantum information.
Article
Chemistry, Multidisciplinary
Haihong Zheng, Hongli Guo, Shula Chen, Biao Wu, Shaofei Li, Jun He, Zongwen Liu, Gang Lu, Xidong Duan, Anlian Pan, Yanping Liu
Summary: WSe2/WSe2 homobilayers with different twist angles were synthesized using a heteroatom-assisted chemical vapor deposition (CVD) technique. The uniformity of the moire superlattices in the homobilayers fabricated by CVD was mapped using low-frequency Raman scattering, demonstrating strong interfacial coupling. The moire potential depths of the CVD-grown and artificially stacked homostructures with a twist angle of 1.5 degrees were 115 and 45 meV (an increase of 155%), indicating the modulation of moire potential depth through interfacial coupling.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Jia Min Ang, Putu Andhita Dananjaya, Samuel Chen Wai Chow, Gerard Joseph Lim, Chim Seng Seet, Wen Siang Lew
Summary: This work demonstrates oscillation frequency modulation in a NbO2-based relaxation oscillator device, where the oscillation frequency increases with temperature and voltage, and decreases with load resistance. Annealing at 373 K was conducted to optimize the stoichiometry of the bulk NbO2 for consistent frequency shift. The device exhibits stable self-sustained oscillation, with frequency tunability between 2 and 33 MHz and a wider voltage range.
Article
Chemistry, Physical
Hong Zhao, Zhong Zheng, Haoruo Zhou, Li Chang, Kostadinos Tsoutas, Limei Yang, Seyedeh K. H. Alavi, Yanping Liu, Behnam Akhavan, Marcela M. Bilek, Zongwen Liu
Summary: High entropy alloys (HEAs) are a new class of materials with high strength, high corrosion and oxidation resistance, and superb thermal stability. In this study, AlCrFeCoNiCu0.5 HEA thin films were fabricated using cathodic arc deposition, and the growth mechanisms and microstructures of the films were investigated by varying arc and duct currents. The crystallography of the films was analyzed using X-ray diffraction (XRD), and the film chemistry and microstructure of the film-substrate interphase were comprehensively studied using transmission electron microscopy (TEM). The results show that the grain size, hardness, and surface roughness of the HEA thin films can be effectively controlled. This study has important implications for the industrial-scale fabrication of HEA thin films using cathodic arc deposition.
SURFACES AND INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Mun Yin Chee, Putu Andhita Dananjaya, Gerard Joseph Lim, Calvin Xiu Xian Lee, Lingli Liu, Wen Siang Lew
Summary: The readout margin of the one selector-one RRAM crossbar array architecture is strongly influenced by the nonlinearity of the selector device. This study demonstrates that the nonlinearity of Pt/TiO2/Pt exponential selectors increases with decreasing oxygen vacancy defect density. The researchers found that the conduction mechanisms transition from Schottky emission to Poole-Frenkel emission with an increase in sputtering pressure, attributed to the rise in oxygen vacancy concentration. Additionally, the short-term plasticity feature of the Pt/TiO2/Pt selector is enhanced with a lower defect density.
Article
Optics
Haihong Zheng, Biao Wu, Shaofei Li, Jun He, Zongwen Liu, Chang-Tian Wang, Jian-Tao Wang, Ji-An Duan, Yanping Liu
Summary: We demonstrate the generation and detection of strained localized excitons in monolayer WSe2 by fabricating strained structures using nanoindentation technique. Enhanced emission of strain-localized excitons is observed with two sharp photoluminescence peaks. The valley polarization of strained localized excitons is increased, reaching a high value of approximately 79.6%, by modulating a magnetic field. These findings highlight the potential of tunable valley polarization and localized excitons in WSe2 monolayers for valleytronic applications.
Article
Chemistry, Multidisciplinary
Haihong Zheng, Biao Wu, Chang-Tian Wang, Shaofei Li, Jun He, Zongwen Liu, Jian-Tao Wang, Ji-an Duan, Yanping Liu
Summary: This work synthesizes a twisted WSe2 homotrilayer and investigates the enhancement of the moire potential with increasing number of twisted layers. The study reveals the presence of multiple exciton resonances confined to the moire potential in the WSe2 homostructure with small twist angles. The moire potential depths of the twisted bilayer and trilayer homostructures are found to be 111 and 212 meV, respectively, an increase of 91% from the bilayer structure.
Article
Optics
Haihong Zheng, Biao Wu, Shaofei Li, Junnan Ding, Jun He, Zongwen Liu, Chang-Tian Wang, Jian-Tao Wang, Anlian Pan, Yanping Liu
Summary: This study presents experimental evidence of localization-enhanced moire excitons in twisted WSe2/WS2/WSe2 heterotrilayers. The confinement effect of moire potential on moire excitons is demonstrated through changes in temperature, laser power, and valley polarization. The findings have implications for the localization of moire excitons and the development of coherent quantum light emitters.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Physics, Applied
Mangyuan Ma, Wen Siang Lew, Fusheng Ma
Summary: In this study, multiple nonvolatile skyrmion states were observed and demonstrated in nanostructured synthetic antiferromagnetic [Pt/Co]4/Ru/[Co/Pt]4 multilayers at room temperature. The results provide evidence for the concept of skyrmion-based nonvolatile memory, such as skyrmion-based memristors and artificial synapses or neurons.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Applied
H. Y. Poh, C. C. I. Ang, G. J. Lim, T. L. Jin, S. H. Lee, E. K. Koh, F. Poh, W. S. Lew
Summary: This study demonstrates the preservation of the topological surface state and enhancement of spin-orbit-torque efficiency at the Co/Bi-Sb(012) interface through the use of various nonmagnetic insertion layer materials. The crystallinity control of Bi-Sb(012) is found to play a crucial role in determining the spin-orbit-torque efficiency. These findings pave the way for the utilization of topological insulators as low-energy spin source materials in spintronics applications.
PHYSICAL REVIEW APPLIED
(2023)
Letter
Chemistry, Physical
Jin-Lin Yang, Lingli Liu, Zehua Yu, Pengbo Chen, Jia Li, Putu Andhita Dananjaya, Eng Kang Koh, Wen Siang Lew, Kang Liu, Peihua Yang, Hong Jin Fan
Summary: A 60 nm artificial protective layer called GZH, with a spatial dielectric-metallic gradient composition, is developed through Zn and HfO2 cosputtering. This design effectively suppresses hydrogen evolution and promotes dendrite-free Zn deposition. With stable battery operation at high currents, the full-cell battery delivers a capacity retention of around 75% after 2000 cycles when paired with a vanadate cathode.
ACS ENERGY LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Kunqi Hou, Shuai Chen, Akshay Moudgil, Xihu Wu, Teck Lip Dexter Tam, Wen Siang Lew, Wei Lin Leong
Summary: This study explores the use of thermoplastic polyurethane (TPU)-based solid electrolyte in organic electrochemical transistors (OECTs). In situ spectrochemistry confirms the doping/dedoping process of conjugated semiconductors by the TPU-based solid electrolyte. The fabricated solid-state OECTs (SSOECTs) demonstrate robustness, high stability, and flexibility, and can operate under varying temperatures. Additionally, inverter circuits using SSOECTs show higher gain compared to the unipolar design when based on n-type and p-type OECTs.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Xing Xie, Junnan Ding, Biao Wu, Haihong Zheng, Shaofei Li, Chang-Tian Wang, Jun He, Zongwen Liu, Jian-Tao Wang, Yanping Liu
Summary: This study presents a dynamic tuning method for twisted WSe2/WSe2 homobilayers and demonstrates the powerful tuning of interlayer coupling. It is found that the introduction of a moire superlattice leads to hybridized excitons and different pressure-evolution exciton behaviors compared to natural bilayers.
Article
Optics
Biao Wu, Xing Xie, Haihong Zheng, Shaofei Li, Junnan Ding, Jun He, Zongwen Liu, Yanping Liu
Summary: This study reveals the possibility of introducing artificial anisotropy in symmetric 2D semiconductors through interlayer van der Waals coupling engineering. By analyzing the photoluminescence spectra and Raman spectra, we discovered the anisotropic optical properties of monolayer MoSe2 and provided a conceptual blueprint for designing isotropic and anisotropic heterostructures.
Article
Engineering, Electrical & Electronic
Kunqi Hou, Shuai Chen, Akshay Moudgil, Xihu Wu, Teck Lip Dexter Tam, Wen Siang Lew, Wei Lin Leong
Summary: In this study, thermoplastic polyurethane (TPU)-based solid electrolyte was used for the first time in organic electrochemical transistors (OECTs). Three types of ionic liquids were blended with TPU polymer matrix as a solid electrolyte for OECTs based on different p-type conjugated semiconductors. The doping/dedoping process of these conjugated semiconductors by TPU-based solid electrolyte was confirmed through in situ spectrochemistry study. The fabricated solid-state OECTs (SSOECTs) showed high stability under continuously applied bias, long time operation, and varying temperatures, and highly flexible SSOECTs were obtained on a polyethylene terephthalate (PET) substrate with negligible fluctuations in on/off-current (Ion/Ioff) after 1000 bending cycles. Based on these high performing SSOECTs, inverter circuits were fabricated with higher gain in complementary configurations.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Physical
Sergey Yu. Ketkov, Sheng-Yuan Tzeng, Elena A. Rychagova, Anton N. Lukoyanov, Wen-Bih Tzeng
Summary: Metallocenes, including methylcobaltocene, play important roles in various fields of chemistry. The ionization energy and vibrational structure of (Cp ')(Cp)Co can be influenced by introducing methyl substituents. The mass-analyzed threshold ionization spectrum and DFT calculations provide accurate information about the properties and transformations of (Cp ')(Cp)Co.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Review
Chemistry, Physical
Qifeng Mu, Jian Hu
Summary: Polymer mechanochemistry has experienced a renaissance due to the rapid development of mechanophores and principles governing mechanochemical transduction or material strengthening. It has not only provided fundamental guidelines for converting mechanical energy into chemical output, but also found applications in engineering and smart devices.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Da Hye Yang, Francesco Ricci, Fredrik L. Nordstrom, Na Li
Summary: Through systematic evaluation of the oiling-out behavior of procaine, we identified both stable and metastable liquid-liquid phase separation, and established phase diagrams to assist in rational selection of crystallization strategies.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Vikki Anand Varma, Simmie Jaglan, Mohd Yasir Khan, Sujin B. Babu
Summary: Designing engineering structures like nanocages, shells, and containers through self-assembly of colloids is a challenging problem. This work proposes a simple model for the subunit, which leads to the formation of monodispersed spherical cages or containers. The model with only one control parameter can be used to design cages with the desired radius.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Hainan Jiang, Yaolong He, Xiaolin Li, Zhiyao Jin, Huijie Yu, Dawei Li
Summary: The cycling lifespan and coulombic efficiency of lithium-ion batteries are crucial for high C-rate applications. The Li-ion concentration plays a crucial role in determining the mechanical integrity and structural stability of electrodes. This study focuses on graphite as the working electrode and establishes an experimental system to investigate the mechanical properties of composite graphite electrode at different C-rates. Considering the effect of Li-ion concentration in stress analysis is found to be significant.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Zhiye Wang, Yunchuan Li, Mingjun Sun
Summary: This study investigates the influence of intramolecular pi-pi interactions on the electronic transport capabilities of molecules. By designing and analyzing three pi-conjugated molecules, the researchers observe that different pi-conjugated structures have varying effects on electron transport. The findings provide a theoretical foundation for designing single-molecule electronic devices with multiple electron channels based on intramolecular pi-pi interactions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Yuandong Xu, Haoyang Feng, Chaoyang Dong, Yuqing Yang, Meng Zhou, Yajun Wei, Hui Guo, Yaqing Wei, Jishan Su, Yingying Ben, Xia Zhang
Summary: Hollow MoS2 cubes and spheres were successfully synthesized using a one-step hydrothermal method with the hard template method. The hollow MoS2 cubes exhibited higher specific capacitance and energy density compared to the hollow MoS2 spheres. The symmetrical supercapacitors assembled with these hollow structures showed good performance and high capacity retention after multiple cycles. These findings suggest that controlling the pore structure and surface characteristics of MoS2 is crucial for enhancing its electrochemical properties.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Ainhoa Oliden-Sanchez, Rebeca Sola-Llano, Joaquin Perez-Pariente, Luis Gomez-Hortiguela, Virginia Martinez-Martinez
Summary: The combination of photoactive molecules and inorganic structures is important for the development of advanced materials in optics. In this study, bulky dyes were successfully encapsulated in a zeolitic framework, resulting in emission throughout the visible spectrum.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Miaomiao Zhang, Cunyuan Pei, Qiqi Xiang, Lintao Liu, Zhongxu Dai, Huijuan Ma, Shibing Ni
Summary: The design of a solid electrolyte interphase (SEI) plays a crucial role in improving the electrochemical performance of anode materials. In this study, lithium difluoro(oxalate)borate (LiDFOB) is used as an electrolyte additive to form a protective SEI film on Li3VO4 (LVO) anodes. The addition of LiDFOB results in a dense, uniform, stable, and LiF-richer SEI, which enhances the Li-ion storage kinetics. The generated SEI also prevents further decomposition of the electrolyte and maintains the morphology of LVO anodes during charge/discharge processes. This work demonstrates the effectiveness of LiDFOB as a multi-functional additive for LiPF6 electrolytes and provides insights into SEI construction for high-performance LVO anodes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
B. V. Andryushechkin, T. V. Pavlova, V. M. Shevlyuga
Summary: The atomic structure of the Ag(111)-p(4 x 4)-O phase was reexamined and two phases with the same periodicity were discovered. It was demonstrated that the accepted Ag6 model is incompatible with high-resolution oxygen-sensitive STM images.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
S. L. Romo-Avila, D. Marquez-Ruiz, R. A. Guirado-Lopez
Summary: In this study, we used density functional theory (DFT) calculations to investigate the interaction between model graphene oxide (GO) nanostructures and chlorine monoxide ClO. We aimed to understand the role of this highly oxidizing species in breaking C-C bonds and forming significant holes on GO sheets. Our results showed that C-C bonds in a single graphene oxide sheet can be broken through a simple mechanism involving the dissociation of two chemically attached ClO molecules. The formation of carbonyl groups and holes on the GO surface was also observed. This study provides important insights into the degradation of carbon nanotubes and the stability of GO during the myeloperoxidase (MPO) catalytic cycle.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Alberto Garcia-Fernandez, Birgit Kammlander, Stefania Riva, Hakan Rensmo, Ute B. Cappel
Summary: In this study, the X-ray stability of five different lead halide perovskite compositions (MAPbI3, MAPbCl3, MAPbBr3, FAPbBr3, CsPbBr3) was investigated using photoelectron spectroscopy. Different degradation mechanisms and resistance to X-ray were observed depending on the crystal composition. Overall, perovskite compositions based on the MA+ cation were found to be less stable than those based on FA+ or Cs+. Metallic lead formation was most easily observed in the chloride perovskite, followed by bromide, and very little in MAPbI3. Multiple degradation processes were identified for the bromide compositions, including ion migration, formation of volatile and solid products, as well as metallic lead. CsBr was formed as a solid degradation product on the surface of CsPbBr3.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Timofei Rostilov, Vadim Ziborov, Alexander Dolgoborodov, Mikhail Kuskov
Summary: The shock-loading behavior of nanomaterials is investigated in this study. It is found that shock compaction waves exhibit a distinct two-step structure, with the formation of faster precursor waves that travel ahead of the main compaction waves. The complexity of the shock Hugoniot curve of the tested nanomaterial is described, and the effect of initial porosity on the compressed states is demonstrated.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Sergey S. Nikitin, Alexander D. Koryakov, Elizaveta A. Antipinskaya, Alexey A. Markov, Mikhail V. Patrakeev
Summary: The stability of La1/3Sr2/3Fe1-xMnxO3-delta, a perovskite-type oxide, under reducing conditions is dependent on the manganese content. Increasing the manganese content leads to a decrease in stability. The behavior of iron and manganese in the oxide shows distinct differences, which can be attributed to the difference in the enthalpy of oxidation reactions. Additionally, the change in the La/Sr ratio affects the concentration of iron and manganese ions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Physical
Mosayeb Naseri, Shirin Amirian, Mehrdad Faraji, Mohammad Abdur Rashid, Maicon Pierre Lourenco, Venkataraman Thangadurai, D. R. Salahub
Summary: Inspired by the successful transfer of freestanding ultrathin films of SrTiO3 and BiFeO3, this study assessed the structural stability and investigated the electronic, optical, and thermoelectric properties of a group of two-dimensional perovskite-type materials called perovskenes. The findings revealed that these materials are wide bandgap semiconductors with potential application in UV shielding. Moreover, they exhibit better electrical and thermal conductivity at high temperatures, enabling efficient power generation in thermoelectric devices.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)