Article
Chemistry, Multidisciplinary
Chen Zhou, Hio Tong Ngan, Jin Soo Lim, Zubin Darbari, Adrian Lewandowski, Dario J. Stacchiola, Boris Kozinsky, Philippe Sautet, Jorge Anibal Boscoboinik
Summary: Dynamic restructuring of bimetallic catalysts is crucial for their catalytic activity and selectivity. The authors use CO as a probe and agent to induce surface restructuring in Pd/Au(111) catalysts, uncovering the kinetics and timescale of in situ restructuring. This minute-timescale dynamics provides insights into the fluxional nature of alloy catalysts and the opportunity for surface fine-tuning under moderate conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
David L. Molina, Maki Inagaki, Emiko Kazuma, Yousoo Kim, Michael Trenary
Summary: Reflection absorption infrared spectroscopy and temperature-programmed desorption experiments were carried out to investigate the properties of Pt/Cu(111) surfaces. Pt coverage on Cu(111) was varied from multilayer to 0.23 monolayer. As the Pt coverage decreased, isolated Pt atoms and Pt islands were observed, indicating the presence of Pt atoms embedded in the Cu(111) surface. Low coverages of Pt at different temperatures formed single atom alloys (SAAs) with surface Pt only present as isolated atoms replacing Cu atoms in the topmost atomic layer. Adsorption of CO on the Pt atoms of the SAAs led to red-shifted C-O stretch peaks compared to CO on Pt(111), indicating how nearby Cu atoms alter the Pt-CO bonding.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Guang Wu, Wang-Ping Xu, Hua-Mei Zuo, Xiao-Lin Wei, Jue-Xian Cao
Summary: This study investigates the adsorption behavior and interaction mechanism of formaldehyde molecules on the Pd/ Au(1 1 1) surface using first-principles computations. The results reveal that Pd metal can function as an excellent sensitive material for formaldehyde detection. The research paves the way for developing high-performance gas sensors.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Mei Xue, Jianfeng Jia, Haishun Wu
Summary: The research investigates the impact of different structural units on the CO adsorption performance using density functional theory, and finds that Pt trimer catalyst exhibits a stronger CO adsorption capacity. The study also explores the effects of different Pt structural units on the C-O bond in CO molecules.
COMPUTATIONAL AND THEORETICAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Jixuan Zhang, Pengfei Tian, Aihao Xu, Like Ouyang, Zixu Yang, Jing Xu
Summary: This study presents an environmentally friendly and economically alternative method for the direct synthesis of H2O2 from H-2 and O-2 via heterogeneous catalysis. By optimizing the electronic and geometric structures of the active metals, the limitations of hydrogenation rate and H2O2 selectivity can be overcome. This work developed an effective strategy for fabricating highly active and stable Pd-based catalysts for H2O2 synthesis with high yield.
CHINESE CHEMICAL LETTERS
(2023)
Article
Chemistry, Physical
N. A. Karim, M. S. Alias, S. K. Kamarudin
Summary: The study focuses on the mechanism of water splitting and glycerol dehydrogenation using Au metal and PdAu alloy catalysts, with results showing that Pd3Au1 catalyst surface is most effective for water splitting and Pd1Au3 catalyst surface has strong adsorption of glycerol.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Jinfan Chen, Li Hu, Tao Tang
Summary: Palladium metal and its alloys play an important role in hydrogen storage and purification, but are susceptible to surface adsorption inhibition by impurities like CO2 and CO. In this study, density functional theory calculations coupled with microkinetic modelings were used to analyze and compare the reaction processes occurring on different Pd surfaces when exposed to mixing gases of H-2 + CO2 and H-2 + CO. The results showed that perfect Pd surfaces are nonactive for catalyzing CO2-to-CO reactions, while CO has a notable effect on retarding hydrogen adsorption on perfect Pd surfaces. The rate-limiting steps for CO2-to-CO reactions mainly involve COOH formation and dissociation, while for H-2 + CO reactions, it is the dissociation of COH species.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Xiuqin Dong, Changdong Li, Minhua Zhang
Summary: By studying the adsorption and dissociation processes of H2S on the surfaces of Co-Cu catalysts, the interaction between the catalyst and H2S and the sulfur poisoning mechanism on the catalyst can be clarified. This provides insights for improving the sulfur tolerance of Co-Cu catalysts.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Tomas Ricciardulli, Sahithi Gorthy, Jason S. Adams, Coogan Thompson, Ayman M. Karim, Matthew Neurock, David W. Flaherty
Summary: The study demonstrates that increasing the ratio of Au to Pd is beneficial for enhancing the selectivity of H2O2 synthesis in water solvent, and there are differences in the transition states of H2O2 and H2O formation pathways.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Haiyang Wang, Dongxia Zhang, Ruiyin Zhang, Hao Ma, Huimin Zhang, Ruijuan Yao, Miaomiao Liang, Yuzhen Zhao, Zongcheng Miao
Summary: Nanorod-structured (Au-Pd)/CeO2 catalysts with different Au/Pd ratios were prepared through dealloying and calcination treatment. Characterization techniques were used to study the structure and physicochemical properties. The (Pd0.15-Au0.15)/CeO2 catalyst calcined at 500°C showed the highest catalytic activity for CO oxidation, reaching 50% and 99% conversion temperatures as low as 50°C and 85°C, respectively. This superior catalytic property is attributed to the robust nanorod structure and introduction of Pd and Au.
Article
Chemistry, Physical
Tianhui Liu, Tianze Peng, Bina Fu, Dong H. Zhang
Summary: This study investigates the reactivity of HCl on a strained Ag monolayer on Au(111) surface. The research finds that despite a lower barrier for HCl+Ag/Au(111) than pure Ag(111), the Ag-Au interaction significantly suppresses the reactivity of HCl. This suppression is attributed to charge transfer between Ag and Au, where electronegative Au makes the top Ag layer on Ag/Au(111) electropositive, unlike that on pure Ag(111). The electropositive Ag attracts Cl, resulting in an unfavorable H-Cl configuration and reduced reactivity. These findings deepen our understanding of polar molecule interactions on bimetallic surfaces and have implications for catalyst design in heterogeneous catalysis.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Konstantin M. Schuttler, Joachim Bansmann, Albert K. Engstfeld, R. Jurgen Behm
Summary: The study reveals that the formation of ZnOx thin films on the Au (111) surface involves oxidation and annealing processes, especially at temperatures above room temperature. Under O2 and NO2 conditions, ZnO/Au(111) thin films can be efficiently prepared by reactive deposition of Zn and annealing.
Article
Chemistry, Multidisciplinary
Robert Bavisotto, Nicholas Hopper, Alejandro Boscoboinik, Quintus Owen, Wilfred T. Tysoe
Summary: Electron and X-ray diffraction, electron microscopy, and reflection-absorption infrared spectroscopy are used to study the structures of thin organic films on metal substrates. The chemical nature and molecular conformations of the film can be determined from the vibrational frequencies, and the film orientation can be obtained using infrared selection rules. The study on furfural adsorbed on gold and palladium substrates shows that the substrate reactivity influences the film structure, with changes in the furfural film's conformation and order observed with variations in film thickness and temperature.
Article
Green & Sustainable Science & Technology
Z. Zhang, X. Liu, Y. Hu, X. Zhou
Summary: Based on density functional theory, the adsorption processes of fluorine-containing gases on different surfaces were investigated. Co and Pd doping greatly improved the adsorption properties of adsorbents for F2 and SOF2 gas molecules. New chemical bond formation occurred during the adsorption process, leading to different adsorption behaviors.
MATERIALS TODAY SUSTAINABILITY
(2023)
Article
Multidisciplinary Sciences
Xiaoyang Huang, Ouardia Akdim, Mark Douthwaite, Kai Wang, Liang Zhao, Richard J. Lewis, Samuel Pattisson, Isaac T. Daniel, Peter J. Miedziak, Greg Shaw, David J. Morgan, Sultan M. Althahban, Thomas E. Davies, Qian He, Fei Wang, Jile Fu, Donald Bethell, Steven McIntosh, Christopher J. Kiely, Graham J. Hutchings
Summary: This study demonstrates that the reaction rate can be almost doubled by separating the gold and palladium components in bimetallic carbon-supported catalysts. The enhancement is attributed to the coupling of separate redox processes occurring at isolated gold and palladium sites.
Article
Physics, Multidisciplinary
Maurice Franck Kenmogne Ndjoko, Bi-Dan Guo, Yin-Hui Peng, Yu-Jun Zhao
Summary: In this study, the ferroelectric properties of monolayer group-IV monochalcogenides MX (M=Sn, Ge; X=Se, Te, S) were investigated through strain engineering, and the effects of contaminated hydrogen were discussed. It was found that the band gap of these materials can be adjusted by strain for excellent photovoltaic applications. Additionally, the most stable hydrogen occupancy location in the monolayer SnS and SnTe was determined, and it was revealed that hydrogen molecules have little effect on the polarization and electronic structure of these materials.
Article
Chemistry, Physical
Xingyu Zhou, Xiaotong Yan, Changchun He, Xiao-Bao Yang, Yu-Jun Zhao
Summary: In this study, the adsorption and dissociation of hydrogen molecules on Mg17Al12(100), Mg17Al12(110), Mg17Al12(111), and Mg(0001) surfaces were investigated using first-principles calculations. It was found that the H adsorption on Mg17Al12 systems exhibited greater strength than that of Mg(0001) surface. Among them, the lowest adsorption energies of H atoms were observed on the Mg17Al12(110) surface, with values of -0.278 and -0.247 eV/H at H coverage of 1/11 and 2/11 ML, respectively. Additionally, the Mg17Al12(110) surface demonstrated a hydrogen dissociation energy path with a minimum barrier of 0.59 eV, which was smaller than that of the Mg(0001) surface (0.84 eV). Electronic structure analysis indicated that although H atoms obtained similar charges on the Mg17Al12(110) and Mg(0001) surfaces, the bonding between H atoms and the Mg17Al12(110) surface was enhanced. Furthermore, the reduced dissociation barriers on the three investigated Mg17Al12 surfaces were likely attributed to the stronger hybridization of H 1s and Al 3s orbitals, resulting in accelerated hydrogen adsorption kinetics on the Mg17Al12 surface compared to the pure Mg surface.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Physics, Applied
Yin-Hui Peng, Chang-Chun He, Yu-Jun Zhao, Xiao-Bao Yang
Summary: Oxygen vacancy is important for the optical properties in In 2O 3, but the single oxygen vacancy model cannot explain the observed multi-peak emission in the experiment. In this study, we have theoretically investigated the diversity of oxygen vacancy distribution and revealed the relationship between defect configurations and optical properties. Our findings provide a comprehensive understanding of the multi-peak emission observed in In 2O 3 and can be extended to modulate the optical properties in other metal oxides.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Jia-Yi Lin, Zhong-Jia Chen, Zhipeng Cao, Jiarui Zeng, Xiao-Bao Yang, Yao Yao, Yu-Jun Zhao
Summary: Magnetic topological materials are attracting attention for their novel topological properties and magnetic configurations. MnBi2Te4/(Bi2Te3)n family, in particular, highlights the research of multiple magnetic topological materials. Based on first-principles calculations, we predict that Mn(Bi, Sb)4Se7, which are close relatives of the MnBi2Te4/(Bi2Te3)n family, have nontrivial topological properties in both antiferromagnetic and ferromagnetic configurations. Our work provides more opportunities for studying magnetic topological physics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Multidisciplinary
Shu-Ming Wu, Chang-Chun He, Yu-Jun Zhao, Rong Liu, Xiao-Bao Yang
Summary: In this paper, the dynamic of hydrogen diffusion in the VCr alloy is investigated using first-principles calculations and the kinetic Monte Carlo method. The structural stability and hydrogen diffusivity are explored as functions of components, revealing that the diffusion is influenced by the spatial distribution of barriers. A one-dimensional random walk model is proposed to describe the anomalous hydrogen diffusion and explain the mechanism of hydrogen migration in the alloy.
Article
Materials Science, Multidisciplinary
Liling Mo, Xiong Zhou, Xuhong Liu, Meiyan Zhan, Yu-Jun Zhao, Jun Du
Summary: The microstructure and thermal-physical properties of Al-xNi (x = 6-25 wt.%) alloys were investigated. The volume fraction and size of Al3Ni increased significantly with the increase of Ni content, while the morphology remained unchanged. The thermal expansion coefficient (CTE) and thermal conductivity (TC) both decreased. The CTE of Al-6 wt.%Ni alloy was 20.2 x 10-6/K at 100°C, decreasing to 15.4 x 10-6/K for Al-25 wt.%Ni, indicating favorable thermal expansion performance. The TC ranged from 202.8 W/(m·K) to 103.9 W/(m·K). Additionally, the structure and thermal properties of Al3Ni were studied using first-principles calculation to provide relevant thermodynamic data. The linear CTE of Al3Ni at 100°C was found to be 13.82 x 10-6/K. Based on experimental and computational results, the modified Turner and general Effective Medium Theory (GEMT) models were used to explain the relationship between microstructure and thermal expansion coefficient, thermal conductivity of Al-xNi alloys.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Liling Mo, Minhao Jiang, Xiong Zhou, Yu-Jun Zhao, Jun Du
Summary: This study investigates the effects of Sm/Yb on the microstructure, electrical conductivity, thermal conductivity, and thermal expansion properties of hypereutectic Al-Fe alloys through experiments and first-principles calculations. The results show that the addition of Sm/Yb effectively modifies the primary Al13Fe4 phase, leading to improved electrical conductivity, thermal conductivity, and thermal expansion performance. The modification is attributed to the transformation of the coarse primary intermetallic phase into fine and star-like particles, reducing electron and phonon scattering. Theoretical calculations suggest that the stable adsorption of Sm/Yb on the surface of Al13Fe4 inhibits preferential growth. This study demonstrates the effectiveness of rare earth element modification in controlling primary phase morphology and improving thermal-physical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Wen-Qiang Xie, Chang-Chun He, Xiao-Bao Yang, Yu-Jun Zhao, Wen-Tong Geng
Summary: Applying in-plane strain can induce a discontinuous transition in the interlayer magnetic coupling of two-dimensional Fe5GeTe2, and enhance the magnetic anisotropy energy of the system, leading to a sharp transition between in-/off-plane configurations.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Jie Xiong, Yin-Hui Peng, Jia-Yi Lin, Yu-Jie Cen, Xiao-Bao Yang, Yu-Jun Zhao
Summary: The most stable defect in MnSb2Te4 is the Mn antisite defect, which can be enhanced by a Mn-rich growth environment and controlled defect concentration. This defect can modulate the interlayer magnetic coupling and lead to a transition from antiferromagnetism to ferromagnetism.
Article
Physics, Multidisciplinary
De-Zhang Li, Zhi-Wei Lu, Yu-Jun Zhao, Xiao-Bao Yang
Summary: This work studies the stochastic differential equation for spin semiclassical system, deriving the generalized formulation of effective Langevin equation and the corresponding Fokker-Planck equation. The obtained effective Langevin equation accurately describes the distribution in the canonical ensemble for spin semiclassical system. It is a generalization of the stochastic Landau-Lifshitz equation, reducing to the semiclassical equation of motion when the damping term and stochastic term vanish. The explicit expressions for the effective Langevin equation and the corresponding Fokker-Planck equation are shown in both Cartesian coordinates and spherical coordinates.
ACTA PHYSICA SINICA
(2023)
Article
Chemistry, Physical
Jia-Yi Lin, Zhong-Jia Chen, Zhipeng Cao, Jiarui Zeng, Xiao-Bao Yang, Yao Yao, Yu-Jun Zhao
Summary: Magnetic topological materials, such as the MnBi2Te4/(Bi2Te3)n family, have attracted attention due to their strong coupling of novel topological properties and magnetic configurations. In this study, we predict that Mn(Bi, Sb)4Se7, the close relatives of MnBi2Te4/(Bi2Te3)n family, exhibit topological properties in both antiferromagnetic and ferromagnetic configurations. The behavior of surface states in these materials depends on the magnetization directions and surface orientations, providing new opportunities for the study of magnetic topological physics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Xing-Yuan Chen, Jin-Long Yang, Li-Fang Chen, Hua-Kai Xu, Jin-Man Chen, Guo-Xia Lai, Xiang-Fu Xu, Hong Ji, Jia-Jun Tang, Yu-Jun Zhao
Summary: Polarized structured nitride semiconductors, such as Mg2XN3, show unique and environmentally friendly electronic properties. This study used first principles calculations to determine the stability, ferroelectricity, and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W). The results suggest that Mg2XN3 (X = Sb, Ta, Bi, and Nb) are stable polar nitrides with potential applications in photocatalytic water splitting and photovoltaics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Dan Huang, Changqing Lin, Yang Xue, Shiyou Chen, Yu-Jun Zhao, Clas Persson
Summary: In this paper, the electronic structure and defect properties of the promising absorber Cu3SbS4 have been studied by first-principles calculations. The suitable preparation conditions for Cu3SbS4 as an absorber are proposed, and isovalent element alloying is demonstrated to be an effective way to improve the material properties by increasing the gap energy.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Hai-Shan Zhang, Lin Shi, Zheng-Hui Liu, Geng-Zhao Xu, Wen-Tao Song, Ya-Kun Wang, Zhong-Jie Xu, Xiao-Bao Yang, Yu-Jun Zhao, Xue-Lin Yang, Bo Shen, Lin-Wang Wang, Ke Xu
Summary: In this study, we propose a method to simulate defect-related luminescence processes based on the SRH model, covering timescales from picoseconds to milliseconds. We validate the feasibility of this method in an n-type GaN sample and obtain simulation results that are consistent with experimental decay lifetimes.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Chang-Chun He, Shao-Gang Xu, Shao-Bin Qiu, Chao He, Yu-Jun Zhao, Xiao-Bao Yang, Hu Xu
Summary: The atomic structure of the metallic glass of Au-Si alloy, which has been discovered recently, consists of Au8Si dodecahedrons with local five-fold symmetry as building blocks. The interconnection modes of Au8Si dodecahedrons play a crucial role in determining the medium-range order. Surface ordering is attributed to the motif transformation of Au8Si dodecahedrons into planar Au5Si pyramids with five-fold symmetry, leading to the self-assembly of Au5Si pyramids and the formation of an ordered Au2Si monolayer with the lowest energy.
