Article
Multidisciplinary Sciences
Nelson Y. Dzade
Summary: Cu2SrSnS4 (CSTS) is a promising alternative material for photovoltaic applications, with efficient light absorption and ideal electronic and optical properties. Interface band offset engineering can improve charge carrier separation and power conversion efficiencies of CSTS for enhanced solar energy conversion.
SCIENTIFIC REPORTS
(2021)
Article
Nanoscience & Nanotechnology
Xianghe Liu, Zhixiong Yang, Zhenhua Zhang, Hua Zhang, Hui Zou
Summary: Stacking two or more 2D materials into a vertical heterostructure is a method to obtain excellent electronic properties. In this study, the energy band alignment, strain, and electric field effects of Arsenene/SnS2 heterostructures are investigated. The results show that the heterostructure has a smaller band gap compared to Arsenene monolayer. It has type II band alignment, which can effectively separate photo-generated electron-hole pairs. The band gap of the heterostructure can be tuned by vertical strain and electric field, with the electric field even enabling the transition from semiconductor to metal. These findings indicate the great potential of heterostructures in optoelectronic devices and photovoltaics.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2022)
Article
Chemistry, Physical
Nahong Song, Yusheng Wang, Zeming Yuan, Fei Wang
Summary: In this study, density functional theory simulations were used to investigate the properties of the AlN@BSe vertical heterostructure. The results show that the AlN@BSe is mechanically stable and has improved in-plane stiffness compared to pure BSe and AlN monolayers. It exhibits strong infrared light absorption and can undergo band gap transitions under certain conditions. The diverse electronic properties make it highly promising for novel nano-electronic applications.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Leilei Li, Shanshan He, Haojie Ruan, Shan He, Donghui Guo
Summary: The microscopic properties of the 4H-SiC/alpha-Al2O3 interface were comprehensively studied using the first-principles method. The results showed that the O-terminated interfaces had significantly higher interface separation work and bonding strength compared to the Al1- and Al2-terminated interfaces. Additionally, the O-terminated interfaces exhibited larger charge transfer, more interfacial bonds, and larger conduction band offsets, which could effectively prevent leakage current and improve the reliability of SiC/Al2O3 devices.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Shun-Chiao Chan, Yu-Lin Cheng, Bor Kae Chang, Che-Wun Hong
Summary: The research found that different facets of SrTiO3 crystal can complete OER and HER reactions; the built-in potential at the facet junction can effectively promote photo-oxidative and photo-reductive reactions, and density functional theory calculations were used to estimate the potential at the facet junction for a better understanding.
Article
Multidisciplinary Sciences
Shivani Grover, Keith T. T. Butler, Umesh V. V. Waghmare, Ricardo Grau-Crespo
Summary: Using density functional theory, this study investigates the thermodynamic, electronic, and ferroelectric properties of BiCoxFe1-xO3 solid solutions. It finds that cobalt substitution can reduce the band gap and increase the spontaneous polarization. The study also discusses the attractive interaction between cobalt impurities and predicts phase separation into a cobalt-rich phase.
ADVANCED THEORY AND SIMULATIONS
(2023)
Article
Chemistry, Multidisciplinary
Kate Robertson, William G. G. Fortune, Julia A. A. Davies, Anton N. Boichenko, Michael S. S. Scholz, Omri Tau, Anastasia V. V. Bochenkova, Helen H. H. Fielding
Summary: We used various spectroscopy techniques and calculations to investigate the photooxidation of aqueous phenolate at different wavelengths. We found that when the wavelength is equal to or larger than 266 nm, electron ejection occurs from the excited state into the continuum associated with the ground state PhO radical. However, when the wavelength is equal to or smaller than 257 nm, electron ejection also occurs into continua associated with electronically excited PhO radicals, which have faster recombination times than the ground state PhO radicals.
Article
Chemistry, Multidisciplinary
Muhammad Asif, Ayash Alrashdi, Mohammed M. Fadhali, A. Afaq, Abu Bakar
Summary: In this study, the thermoelectric parameters of RuCrX (X = Si, Ge, Sn) half-Heusler alloys were investigated using the pseudopotential approach and Boltzmann transport theory. The results showed that these alloys have a stable C1b-type crystal structure, and their important thermoelectric properties were discussed.
Article
Chemistry, Multidisciplinary
Zahra Golsanamlou, Alessandro Fortunelli, Luca Sementa
Summary: This article introduces a new two-dimensional material -- chlorine-doped ultrathin hafnium disulfide (HfS2), which combines the characteristics of a metal and a semiconductor, enabling the realization of FET devices with purely ohmic behavior, high conductivity, and high on/off ratio.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Swagata Acharya, Dimitar Pashov, Alexander N. Rudenko, Malte Rosner, Mark van Schilfgaarde, Mikhail Katsnelson
Summary: The passage discusses the use of embedding methods to handle strong electronic correlations in materials, measuring success by the quality of the self-energy sigma. It also highlights that factors such as choice of parameters, double-counting corrections, and the adequacy of the low-level Hamiltonian can hinder a clear understanding of these effects in some cases.
NPJ COMPUTATIONAL MATERIALS
(2021)
Article
Chemistry, Inorganic & Nuclear
Sheraz Ahmad, Fawad Khan, Bin Amin, Iftikhar Ahmad
Summary: The physical properties of materials can be tuned for applications in nanoelectronics and renewable energy by stacking two-dimensional materials and applying strain through weak van der Waals interaction. Studies on Janus transition metal dichalcogenides heterostructures have investigated their electronic properties and band alignment, confirming type-I alignment and observing transitions to type-II or type-III alignment with strain. Investigation using semi classical Boltzmann transport theory has shown that these heterostructures have high Seebeck coefficients, making them suitable for thermoelectric devices.
JOURNAL OF SOLID STATE CHEMISTRY
(2021)
Article
Chemistry, Physical
Lihong Han, Yuanyuan Zou, Baonan Jia, Xiaoning Guan, Huiyan Zhao, Yingshi Hu, Xinhui Zhang, Pengfei Lu
Summary: The atomic and electronic properties of different SiC/SiO2 interfaces were investigated using the first principles method. The terminal types on the SiO2 side and crystal faces of 4H-SiC influenced the interface structures and band alignment. The O-terminated interface structures showed higher conduction band offsets and interface separation work, making them more favorable for SiC-based devices.
SURFACES AND INTERFACES
(2022)
Article
Chemistry, Physical
S. Vahid Hosseini, Andrei Postnikov, Mohammad Reza Mohammadizadeh
Summary: Based on first-principles calculations, this study investigates the preferences for hydrogen absorption sites and diffusion paths in cubic (monoclinic) TiO with intrinsic vacancies. Oxygen vacancies are identified as the primary hydrogen traps, while several competitive diffusion channels with barrier heights ranging from 2.87 to 3.71 eV are found. Adsorption of molecular hydrogen is unlikely, as the H-2 molecules easily dissociate upon penetrating the TiO crystal. These results suggest that hydrogen can persist in oxygen vacancy sites up to high temperatures.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Natalya S. Fedorova, Andrea Cepellotti, Boris Kozinsky
Summary: This study uncovers a new phenomenon where the electrical conductivity decreases with carrier concentration, the Seebeck coefficient reverses sign even at high doping, and the power factor exhibits an unusual second peak in materials with multiple bands crossing near the Fermi level. The origin and magnitude of this effect are explained, and general design rules for enhancing performance in thermoelectric materials are identified.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Javad Shirani, Sinan Abi Farraj, Shuaishuai Yuan, Kirk H. Bevan
Summary: This work explores the relative accuracy of a hybrid functional in predicting redox properties while satisfying the general form of Koopmans' theorem. Through direct comparison and first-principles calculations, it is found that employing a total energy difference approach can provide theoretically robust estimates of redox energies when using hybrid functionals.
JOURNAL OF CHEMICAL PHYSICS
(2022)