Article
Chemistry, Multidisciplinary
Yung-Chang Lin, Jeyakumar Karthikeyan, Yao-Pang Chang, Shisheng Li, Silvan Kretschmer, Hannu-Pekka Komsa, Po-Wen Chiu, Arkady V. Krasheninnikov, Kazu Suenaga
Summary: The study investigates post-growth doping of transition metal atoms in single layers of WSe2, successfully achieving high densities of various types of impurity atoms. The dopants are predominantly confined within nanostripes embedded in the pristine WSe2, with dislocations aiding in the incorporation of dopants and the formation of stripes of TM dopant atoms.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Binjie Li, Kunkun Nie, Yujia Zhang, Lixin Yi, Yanling Yuan, Shaokun Chong, Zhengqing Liu, Wei Huang
Summary: A scalable method is developed for the synthesis of single-layer hollow spheres (SLHS) of transition metal dichalcogenides (TMDs) with high 1T-phase purity by etching bismuth (Bi) cores from pre-synthesized Bi@TMDs core-shell heterostructures. The fabricated SLHS-1T-MoS2 exhibits superior electrocatalytic performance.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Hugo Kowalczyk, Johan Biscaras, Nashra Pistawala, Luminita Harnagea, Surjeet Singh, Abhay Shukla
Summary: This study investigates the properties of MoTe2 under different layer thicknesses, temperatures, and electrostatic doping conditions through extensive Raman measurements. The research finds that the 2H-1T' transition in MoTe2 cannot be achieved solely through a pure electrostatic field.
Article
Chemistry, Multidisciplinary
Hugo Kowalczyk, Johan Biscaras, Nashra Pistawala, Luminita Harnagea, Surjeet Singh, Abhay Shukla
Summary: We conducted extensive Raman measurements on 2H-MoTe2, 1T'-MoTe2, and Td-WTe2 to study the effects of layer thickness, temperature, and electrostatic doping. We found that few-layer tellurides exhibit high mobility of Te ions, even in ambient conditions, and external parameters such as electric field or temperature can induce Te clusters, vacancies, and structural transitions. However, we found that the claimed 2H-1T' transition in MoTe2 cannot be achieved solely through electrostatic field.
Article
Chemistry, Physical
Emilia Piosik, Maciej J. Szary
Summary: Despite efforts to limit fossil fuel use, SO2 remains a major air pollutant. Effective and sustainable methods of SO2 monitoring are crucial, but current solutions based on resistive sensors have limitations. This work investigates doping MoS2 with Si, P, Cl, Ge, and Se to improve its SO2 sensing capability.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Ningxin Wei, Hang Li, Jianliang Li, Longlong Sun, Jiewen Huang, Jian Kong, Qiujie Wu, Yan Shi, Dangsheng Xiong
Summary: Doping TMDs films with C/N dual-doping improves their mechanical, tribological, and anti-corrosion properties. The dopants introduce hard phase in TMDs phase and amorphous phase, achieving a balance between lubricating phase effect and mechanical performance.
APPLIED SURFACE SCIENCE
(2024)
Article
Multidisciplinary Sciences
Ranjan Kumar Barik, Lilia M. Woods
Summary: This article introduces a computational dataset of bilayer materials, consisting of 760 structures with their structural, electronic, and transport properties. Different stacking patterns of each bilayer are determined by analyzing the symmetries of their monolayers. Density functional theory calculations, including van der Waals interactions, are performed to evaluate the ground states of each stacking pattern. The dataset can be utilized for materials screening and data-assisted modeling for desired thermoelectric or optoelectronic applications.
Article
Chemistry, Physical
Sonu Prasad Keshri, Swapan K. Pati, Amal Medhi
Summary: In this study, we calculate the carrier mobility of monolayer HfSe2 using density functional perturbation theory and Boltzmann transport equation, and accurately determine the experimental value. Compared to the previously used deformation potential model, we find that the strong electron-optical phonon interaction is one of the reasons for the low mobility. The results also show that the spin-orbit coupling significantly affects the mobility and scattering rates.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Ming-Deng Siao, Yung-Chang Lin, Tao He, Meng-Yu Tsai, Kuei-Yi Lee, Shou-Yi Chang, Kuang- Lin, Yen-Fu Lin, Mei-Yin Chou, Kazu Suenaga, Po-Wen Chiu
Summary: In this study, the growth of WS2 monolayer codoped with multiple kinds of transition metal impurities via chemical vapor deposition is demonstrated. The multi-element embedment of Cr, Fe, Nb, and Mo into the host lattice generates abundant impurity states in the bandgap of WS2, enabling a robust switch of charging/discharging states. Furthermore, doped WS2 field-effect transistors exhibit a profound memory window in their transfer curves, laying the groundwork for robust nonvolatile memory based on binary states.
Article
Materials Science, Multidisciplinary
Z. Ruan, Jianchen Lu, Baijin Li, Qizan Chen, Zhenliang Hao, Lei Gao, Jinming Cai
Summary: In this study, a comprehensive investigation of intrinsic defects in single-layer WS2 grown by chemical vapor deposition was conducted. The results provide guidance for future targeted defect engineering and doping of single-layer transition metal dichalcogenides.
MATERIALS TODAY PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Yuya Murai, Shaochun Zhang, Takato Hotta, Zheng Liu, Takahiko Endo, Hiroshi Shimizu, Yasumitsu Miyata, Toshifumi Irisawa, Yanlin Gao, Mina Maruyama, Susumu Okada, Hiroyuki Mogi, Tomohiro Sato, Shoji Yoshida, Hidemi Shigekawa, Takashi Taniguchi, Kenji Watanabe, Ruben Canton-Vitoria, Ryo Kitaura
Summary: A simple and direct method has been developed for controlled postdoping of 2D transition metal dichalcogenides using low-kinetic-energy dopant beams and high-flux chalcogen beams. The doped TMDs showed significant changes in electronic properties, with p-type action and a drastic increase in current. Position-selective doping was also demonstrated using a patterned mask on the surface, showing the versatility of this postdoping method for future 2D-based electronics.
Article
Nanoscience & Nanotechnology
Juchan Lee, Seungho Bang, Hyeon Jung Park, Dae Young Park, Chulho Park, Ngoc Thanh Duong, Yo Seob Won, Jiseong Jang, Hye Min Oh, Soo Ho Choi, Ki Kang Kim, Mun Seok Jeong
Summary: This study proposes a facile method for n-doping and mediation of Se vacancies in tungsten diselenide (WSe2) by poly(vinylpyrrolidone) (PVP) coating, successfully converting the major carrier type of the PVP-coated WSe2 from hole (p-type) to electron (n-type), while significantly reducing the vacancy-induced interface trap density.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Dechao Chen, Zengxi Wei, Mengjia Wang, Shuangliang Zhao, Pan Liu, Anlian Pan, Yongwen Tan
Summary: This study presents a general method for scalable in situ doping of centimeter-sized nanoporous ReSe2 films with transition metal atoms. The as-prepared nanoporous Ru-ReSe2 film with high 1T phase exhibits excellent electrochemical activity in hydrogen evolution reaction.
Article
Chemistry, Physical
Mengqi Fang, Eui-Hyeok Yang
Summary: Transition metal dichalcogenides (TMDs) are 2D materials with remarkable electrical, optical, and chemical properties. One strategy to modify their properties is through dopant-induced alloy creation. Dopants in TMDs can introduce additional states within the bandgap, leading to changes in optical, electronic, and magnetic properties. This review paper provides a comprehensive summary of dopant-induced magnetic properties and their impact on TMDs, which can guide further research for applications in spintronics, optoelectronics, and magnetic memory devices.
Article
Engineering, Environmental
Mengyao Li, Bihai Cai, Ruoming Tian, Xiaojiang Yu, Mark B. H. Breese, Xueze Chu, Zhaojun Han, Sean Li, Rakesh Joshi, Ajayan Vinu, Tao Wan, Zhimin Ao, Jiabao Yi, Dewei Chu
Summary: This study presents a method to fabricate high-efficiency V-doped MoS2 nanosheets with excellent catalytic performance and stability, providing new insights for hydrogen evolution reaction in water splitting.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Physics, Applied
Saswat Mishra, Kathik Guda Vishnu, Alejandro Strachan
Summary: Gallium nitride (GaN) and AlxGa1-xN are crucial in high-power applications, with their piezoelectric and dielectric constants changing significantly with strain and aluminum content, highlighting the importance of understanding their effects on device performance.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Brenden W. Hamilton, Brad A. Steele, Michael N. Sakano, Matthew P. Kroonblawd, I-Feng W. Kuo, Alejandro Strachan
Summary: 2,6-Diamino-3,5-dinitropyrazine-1-oxide (LLM-105) is a relatively new and promising insensitive high-explosive material. Its early reaction pathways are similar to TATB, while its detonation performance falls between TATB and HMX. Different predictive models provide benchmarks for evaluating uncertainties and show similar reaction rates at high temperatures.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Jason Ford, Stefan Seritan, Xiaolei Zhu, Michael N. Sakano, Md Mahbub Islam, Alejandro Strachan, Todd J. Martinez
Summary: In this study, kinetic models were constructed for the decomposition of nitromethane by using accelerated molecular dynamics simulations and the ReaxFF reactive force field. Thermochemical data from density functional theory was combined with ReaxFF minimal energy paths to correct reaction barriers. The models were validated by predicting gas phase CO and NO concentrations as well as high-pressure induction times similar to experimental data, and fundamental decomposition reactions were identified in different thermodynamic regimes.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Brenden W. Hamilton, Matthew P. Kroonblawd, Chunyu Li, Alejandro Strachan
Summary: When shockwaves interact with a material's microstructure, energy is localized into hotspots, serving as nucleation sites for complex processes. Research shows that the energy localized in hotspots is mainly in the form of potential energy, and large intramolecular strains are identified as the origin of these potential energy hotspots.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Mackinzie S. Farnell, Zachary D. McClure, Shivam Tripathi, Alejandro Strachan
Summary: Complex-concentrated-alloys (CCAs) are of interest for their desirable properties, but modeling their atomic structure is challenging. This study combines atomistic simulations and machine learning to develop predictive models for various atomic properties of CCAs, showing good accuracy.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Physics, Applied
Chunyu Li, Alejandro Strachan
Summary: Molecular dynamics simulations were used to study the shock-induced collapse of porosity and temperature distribution in 1,3,5,7-tetranitro-1,3,5,7-tetrazoctane. The study found that pore size and shape play a crucial role in the collapse mechanism and resulting temperature. The findings provide valuable information for predictive modeling of shock-induced initiation.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Applied
Jalen Macatangay, Brenden W. Hamilton, Alejandro Strachan
Summary: This article reports a transient melting of glassy polymers under shock loading, where high deviatoric stresses induce fast transitions and stress relaxation characteristic of polymer melts before slower relaxation expected for glasses.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Fangyi Shi, Nicolas Onofrio, Chunhong Chen, Songhua Cai, Yanyong Li, Lingling Zhai, Lyuchao Zhuang, Zheng-Long Xu, Shu Ping Lau
Summary: This study reports a method for the generation of liquid sulfur on hydrogen-annealed MoS2 and reveals the mechanism behind the formation of liquid sulfur. High areal capacities are achieved by releasing active H-2-MoS2 surfaces. Other transition metal dichalcogenides annealed in hydrogen also exhibit similar behavior. This research provides new insights for the development of low-temperature lithium-sulfur batteries.
Article
Physics, Applied
Saswat Mishra, Karthik Guda Vishnu, Alejandro Strachan
Summary: Refractory complex concentrated alloys (RCCAs) are a new class of materials with excellent mechanical properties at high temperatures. Determining their melting temperature (T-m) is crucial for assessing their range of operation. However, experimental determination of this property is challenging, making computational tools highly desirable. In this study, we quantified the uncertainties associated with predicting T-m of RCCAs using density functional theory-based molecular dynamics. We employed two methods and found that a combination of free energy calculations and a dynamical coexistence method provided accurate results with minimal computational cost. We predicted the T-m of equiatomic NbMoTaW to be between 3000 and 3100 K.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Physical
Brenden W. W. Hamilton, Pilsun Yoo, Michael N. N. Sakano, Md Mahbubul Islam, Alejandro Strachan
Summary: Reactive force fields have been widely used in molecular dynamics for studying various material classes. They are computationally efficient and capable of simulating millions of atoms. However, the accuracy of traditional force fields is limited by their functional forms. To overcome this limitation, we develop a neural network-based reactive interatomic potential that accurately predicts the mechanical, thermal, and chemical responses of energetic materials at extreme conditions. The new potential outperforms current state-of-the-art force fields in various properties including detonation performance, decomposition product formation, and vibrational spectra.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Polymer Science
Shukai Yao, Chunyu Li, Matthew Jackson, Alejandro Strachan
Summary: Calorimetry and mechanical tests on polyacrylonitrile PAN reveal two glass transitions (Tg). Molecular dynamics (MD) simulations suggest higher Tg for the ordered phase, contradicting experimental observations. To address this discrepancy, a large-scale amorphous PAN sample was mechanically strained to achieve a structure consistent with experiments, demonstrating the coexistence of amorphous and ordered regions. The resulting ordered phase exhibited a hexagonal pattern and nanovoids caused by local deformations and molecular alignment, with significantly faster relaxation dynamics that explain the lower experimental Tg.
Article
Chemistry, Physical
Kun Qi, Yang Zhang, Nicolas Onofrio, Eddy Petit, Xiaoqiang Cui, Jingyuan Ma, Jinchang Fan, Huali Wu, Wensen Wang, Ji Li, Jiefeng Liu, Yupeng Zhang, Ying Wang, Guangri Jia, Jiandong Wu, Luc Lajaunie, Chrystelle Salameh, Damien Voiry
Summary: A supersaturation strategy was employed to electrosynthesize 2-propanol from CO2 using highly carbonated electrolytes. The CuAg alloy catalyst exhibited high performance for 2-propanol production with a faradaic efficiency of 56.7% and at a specific current density of 59.3 mA cm(-2).
Article
Physics, Applied
George Maxwell Nishibuchi, Shivam Tripathi, Saswat Mishra, Clara Rivero-Baleine, Alejandro Strachan
Summary: The combination of optical and mechanical properties of calcium lanthanum sulfide (CLS) makes it an attractive material for optical applications. Density functional theory (DFT) simulations were used to investigate the effect of La2S3/CaS relative fractions on the structural and mechanical properties of single crystalline CLS solid solutions. The results showed a decrease in stiffness with CaS fraction and an increase in lattice parameter with La2S3 fraction. Point defects in CLS were also characterized and their neutral charge state configurations were found to be energetically favorable.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Brian H. Lee, James P. Larentzos, John K. Brennan, Alejandro Strachan
Summary: This study investigates the role of shock-induced plastic deformation in shock initiation using a particle-based model. The simulations reveal that transient behavior can affect hotspot formation and shock-to-deflagration transition under high intensity shock.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Chunyu Li, Juan Carlos Verduzco, Brian H. Lee, Robert J. Appleton, Alejandro Strachan
Summary: The response of materials to shock loading is crucial for planetary science, aerospace engineering, and energetic materials. Deep learning is used to predict the resulting shock-induced temperature fields in composite materials, achieving higher accuracy and lower computation cost compared to current state of the art techniques.
NPJ COMPUTATIONAL MATERIALS
(2023)