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ZHANG WEIBIN, WU AILING, LIU YIDING, ZHANG SHAOLIN, GONG JIANHONG, CHANG LAN, LI JIAN, ZHANG HUI, LIU HAIFENG, LI KEHUA, HUANG KAI, YANG WOOCHUL. FIRST-PRINCIPLES STUDY OF Ti-CATALYZED HYDROGEN ADSORPTION ON LiB (001) SURFACE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2013. [DOI: 10.1142/s021963361350065x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Ti -doped LiB (001) is a promising material for hydrogen storage. The adsorption of H 2 is greatly enhanced by doping Ti into LiB (001), change the electronic structures of the surface Li , B atoms. After H 2 is adsorbed on the surface, the E ad of the ( H 2)n@ Ti / LiB (001) system is considered. It is around -0.22 eV/ H 2 to -0.31 eV/ H 2, which is close to the target specified by U.S. Department of Energy. The nature of the bonding between Ti and H 2 is due to the H 1s, Ti 4s and B 2s orbital hybridization. In addition, Ti 3d orbital is hybridized strongly with B -2p orbital, resulting in more stable Ti / LiB (001) system. These results are verified by the electron density distribution intuitively. It is found that the system can adsorb up to four H 2 at ambient temperature and pressure. Therefore, the Ti -doped LiB (001) would be a promising hydrogen storage material. Such optimal molecular hydrogen adsorption system makes H 2 adsorption feasible at ambient conditions, which is critical for practical applications.
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Affiliation(s)
- WEIBIN ZHANG
- Department of Physics, Dongguk University, Seoul 100-715, Korea
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - AILING WU
- School of Space Science and Physics, Shandong University at Weihai, Weihai 264209, P. R. China
| | - YIDING LIU
- College of Physics and Electronic Engineering, Leshan Normal University, Leshan 614004, P. R. China
| | - SHAOLIN ZHANG
- Department of Physics, Dongguk University, Seoul 100-715, Korea
| | - JIANHONG GONG
- School of Mechanical, Electrical and Information Engineering, Shandong University at Weihai, Weihai 264209, P. R. China
| | - LAN CHANG
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - JIAN LI
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - HUI ZHANG
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - HAIFENG LIU
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - KEHUA LI
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - KAI HUANG
- The Engineering & Technical College of Chengdu, University of Technology, Leshan 614099, P. R. China
| | - WOOCHUL YANG
- Department of Physics, Dongguk University, Seoul 100-715, Korea
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YANG LIXIA, LEI XIAOLI, FENG JUN, ZHANG YUXIN, LIU MINGXING. DENSITY FUNCTIONAL THEORY STUDY OF H2O ADSORPTION AND DISSOCIATION ON Al (111) SURFACE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2013. [DOI: 10.1142/s0219633613500351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Comparative study about the adsorption and dissociation behaviors of H2O molecule on clean and vacancy defective Al (111) surface was conducted by extensive density functional theory (DFT) calculations, the interaction mechanisms between H2O molecule and Al (111) surface were also figured out. Geometry optimization results indicated that H2O molecule was apt to be adsorbed at top site on these two kinds of surfaces, whereas, the adsorption configurations, the adsorption type and inclination of H2O molecule planes away from the normal were different. The calculated adsorption energies demonstrated that the adsorption of H2O molecule occurred more readily on vacancy defective Al (111) surface. The electron density distribution indicated that the vacancy defect enhanced the interactions between H2O molecule and surface Al atoms. Further analysis of the density of states (DOS) showed that the vacancy defect increased the number of bonding electrons between H2O molecule and surface Al atoms. The detailed exploration of dissociation pathways demonstrated that the dissociation of H2O molecule on these two kinds of surfaces was a two-step process: (1) H2O → H + OH , (2) OH → H + O . However, for each step the dissociation pathway variations on vacancy defective Al (111) surface were different with those on clean Al (111) surface. Compared with the first step, the dissociation of hydroxyl group into O atom and H atom was kinetically difficult. The calculated lower activation energy barriers on vacancy defective Al (111) surface showed that the vacancy defect had catalytic effect for the dissociation of H2O molecule to some extent, especially for the first step.
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Affiliation(s)
- LIXIA YANG
- Faculty of Material and Chemistry, China University of Geosciences, Wuhan 430074, P. R. China
| | - XIAOLI LEI
- Faculty of Material and Chemistry, China University of Geosciences, Wuhan 430074, P. R. China
| | - JUN FENG
- R&D Institute for Concrete Delivery Technologies, Sany Group, Changsha 410100, P. R. China
| | - YUXIN ZHANG
- Faculty of Material and Chemistry, China University of Geosciences, Wuhan 430074, P. R. China
| | - MINGXING LIU
- Faculty of Material and Chemistry, China University of Geosciences, Wuhan 430074, P. R. China
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