Showing papers by "Zhiguo Wang published in 2022"
TL;DR: In this article , ultralight SiC/Si3N4 aerogels are prepared by freeze-drying and carbothermal reduction reaction, and their microstructures were investigated by transmission electron microscopy, Raman spectroscopy, and X-ray absorption near-edge structure at the N K-edge.
21 citations
TL;DR: In this article, a long carbon chain ligand with a thiol group, 1-Octadecanethiol (ODT), was promoted to realize the passivation of the surface of CsPbI3 nanocrystals after the synthesis process.
11 citations
TL;DR: Based on different character distribution of twin-related boundaries introduced by special thermomechanical processing, the effect on carbide precipitation and the resulting intergranular corrosion (IGC) behavior was investigated in depth in nuclear-grade 316H stainless steel as discussed by the authors .
4 citations
TL;DR: In this paper , the performance of the CuPS 3 monolayer with transition metal atoms (e.g., Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) was investigated.
Abstract: Abstract The noble metal such as Pt has been used as the catalysts for hydrogen evolution reaction (HER), but with problems such as scarcity of resources and high cost. Anchoring transition metal atoms onto the catalysts is regarded as a potential approach to solve this problem and enhance the electrocatalytic performance of HER. For this purpose, two-dimensional materials, such as CuPS 3 monolayer, are regarded as one of the most ideal carriers for adsorption of metal atoms. However, there is no previous study on this topic. In this paper, we systematically studied microstructures, electronic properties, and electrocatalytic performance of the CuPS 3 monolayer anchored with transition metal atoms (e.g., Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) using a density functional theory (DFT). Results showed that all the transition metal atoms are favorably adsorbed onto the CuPS 3 monolayer with large binding energies at the top of the Cu atom. The pristine CuPS 3 monolayer has a large catalytic inertia for hydrogen evolution reactions, whereas after anchored with transition metal atoms, their catalytic performances have been significantly improved. The Gibbs free energy (Δ G H ) is 0.44 eV for the H atom absorbed onto the pristine CuPS 3 monolayer, whereas the Δ G H values for the V, Fe, and Ni atoms anchored onto the CuPS 3 monolayer are 0.02, 0.11, and 0.09 eV, respectively, which is close to the Δ G H of H atom adsorbed on Pt (e.g., −0.09 eV). At the same time, the influence of hydrogen coverage rate was calculated. The result shows that V adsorbed on CuPS 3 monolayer is catalytic active for HER for a large range of hydrogen coverage. Our results demonstrate that anchoring of V atom onto the CuPS 3 monolayer is a potentially superior method for making the catalyst for the HER. Graphical abstract
2 citations
2 citations
TL;DR: Using density functional theory (DFT) calculations, the Gibbs free energy diagrams and electronic structure of N-graphene, Ir-n4 and Co-N4 are investigated in this article .
Abstract: Electrocatalysis plays very important role in clean energy conversion. In which, developing high active and robust electrocatalysts for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are highly crucial and challenging. Using density functional theory (DFT) calculations, the Gibbs free energy diagrams and electronic structure of N-graphene, Ir-N4 and Co-N4 are investigated in this work. The results show that Co-N4 have the appropriate H adsorption and lower ORR overpotentials, which gives expectation of high multifunctional electrocatalytic performance. This theoretical study provides vital insights into the enhanced electrocatalytic mechanism of Co sites supported on N-doped carbon.
TL;DR: In this article , density functional theory has been used to systematically examine the effects of mechanical strain, including in-plane biaxial strain and out-of-plane strain, on magnetic anisotropy energy (MAE) in YIG and BiYIG.
Abstract: For applications in magnetic memory and spintronic devices, ferrimagnetic insulators (FMIs) with perpendicular magnetic anisotropy (PMA) are of special interest. Because of its low magnetic losses, yttrium iron garnet (Y3Fe5O12, also known as YIG) is frequently regarded as the most promising FMI film. However, YIG films typically have an in-plane easy axis, which limits their potential applications. In YIG films, several strategies are suggested to obtain PMA. In YIG and doped YIG films, the epitaxial strain brought on by lattice mismatch has proven to be a successful method for achieving PMA. The investigation on the theoretical mechanism of PMA induction has not yet been reported, even though PMA has been successfully induced in YIG and other FMIs films. In this study, density functional theory has been used to systematically examine the effects of mechanical strain, including in-plane biaxial strain and out-of-plane strain, on magnetic anisotropy energy (MAE) in YIG and bismuth-doped YIG (BiYIG). The findings demonstrate that unstrained YIG has no magnetic anisotropy. Additionally, it has been found that the easy axis of the YIG may be changed from being in-plane to being out-of-plane by an out-of-plane compressive strain or a modest tensile in-plane biaxial strain. From the examination of the electronic structure, it has been observed that the local density of states close to the Fermi energy is mostly responsible for the shift in MAE. It is anticipated that the modulation of PMA in YIG and the design of spin wave devices based on YIG will both benefit from these results.