Hydrogen Adsorption on Ga2O3 Surface: A Combined Experimental and Computational Study

In the present work, hydrogen adsorption on the Ga2O3 surfaces was investigated using Fourier transform infrared spectroscopy (FTIR) measurements and periodic density functional theory (DFT) calculations. Both the FTIR and DFT studies suggest that H2 dissociates on the Ga2O3 surfaces, producing OH and GaH species. The FTIR bands at 3730, 3700, 3630, and 3600 cm–1 are attributed to the vibration of the OH species whereas those at 2070 and 1990 cm–1 to the GaH species. The structures of the species detected in experiments are established through a comparison with the DFT calculated stretching frequencies. The O atom of the experimentally detected OH species is believed to originate from the three-coordinated surface O atom. However, the H adatom that binds the coordinately unsaturated Ga atom results in the experimentally detected GaH species. Dissociative adsorption of H2 on the perfect Ga2O3 surface, with the formation of both OH and GaH species, is endothermic and has an energy barrier of 0.90 eV. In con...

[1]  Jinshui Zhang,et al.  Synthesis, characterization and photocatalytic activity of β-Ga2O3 nanostructures , 2010 .

[2]  Ping Zhang,et al.  Dissociation of H2 molecule on the β-Ga2O3 (100)B surface: The critical role of oxygen vacancy , 2010, 1108.3451.

[3]  Qingfeng Ge,et al.  Promotion effects of Ga2O3 on CO2 adsorption and conversion over a SiO2-supported Ni catalyst , 2010 .

[4]  H. Yoshida,et al.  Photocatalytic Activation of Water and Methane over Modified Gallium Oxide for Hydrogen Production , 2010 .

[5]  Donghai Mei,et al.  Effects of hydration and oxygen vacancy on CO2 adsorption and activation on beta-Ga2O3(100). , 2010, Langmuir : the ACS journal of surfaces and colloids.

[6]  Tsunehiro Tanaka,et al.  Effect of H2 gas as a reductant on photoreduction of CO2 over a Ga2O3 photocatalyst , 2008 .

[7]  Q. Ge,et al.  Adsorption and protonation of CO2 on partially hydroxylated gamma-Al2O3 surfaces: a density functional theory study. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[8]  T. Yanagida,et al.  Effect of Metal Ion Addition in a Ni Supported Ga2O3 Photocatalyst on the Photocatalytic Overall Splitting of H2O , 2008 .

[9]  G. Rupprechter,et al.  Defect formation and the water–gas shift reaction on β-Ga2O3 , 2008 .

[10]  M. A. Baltanás,et al.  Methanol synthesis from CO2/H2 using Ga2O3–Pd/silica catalysts: Impact of reaction products , 2008 .

[11]  L. Yuliati,et al.  Photocatalytic conversion of methane and carbon dioxide over gallium oxide , 2008 .

[12]  Q. Ge,et al.  Effect of Surface Oxygen Vacancy on Pt Cluster Adsorption and Growth on the Defective Anatase TiO2(101) Surface , 2007 .

[13]  Z. Li,et al.  Photocatalytic performance of α-, β-, and γ-Ga2O3 for the destruction of volatile aromatic pollutants in air , 2007 .

[14]  Xianzhi Fu,et al.  Efficient decomposition of benzene over a beta-Ga2O3 photocatalyst under ambient conditions. , 2006, Environmental science & technology.

[15]  V. Bermudez.  The structure of low-index surfaces of β-Ga2O3 , 2006 .

[16]  Weiming Hua,et al.  Dehydrogenation of propane to propene over different polymorphs of gallium oxide , 2005 .

[17]  M. Delgado,et al.  Infrared Spectroscopic Study on the Surface Properties of γ-Gallium Oxide as Compared to Those of γ-Alumina , 2005 .

[18]  S. Collins,et al.  Hydrogen chemisorption on gallium oxide polymorphs. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[19]  A. Juan,et al.  Hydrogen adsorption on β-Ga2O3(1 0 0) surface containing oxygen vacancies , 2005 .

[20]  K. Yamaguchi.  First principles study on electronic structure of β-Ga2O3 , 2004 .

[21]  Philippe Sautet,et al.  Use of DFT to achieve a rational understanding of acid–basic properties of γ-alumina surfaces , 2004 .

[22]  Yongxiang Li,et al.  Hydrogen sensitive GA2O3 Schottky diode sensor based on SiC , 2004 .

[23]  T. Yanagida,et al.  Photocatalytic Decomposition of H2O into H2 and O2 over Ga2O3 Loaded with NiO , 2004 .

[24]  M. Delgado,et al.  Unexpected similarities between the surface chemistry of cubic and hexagonal gallia polymorphs , 2003 .

[25]  Philippe Sautet,et al.  Hydroxyl Groups on γ-Alumina Surfaces: A DFT Study , 2002 .

[26]  J. Fierro,et al.  Gallium–Hydrogen Bond Formation on Gallium and Gallium–Palladium Silica-Supported Catalysts , 2002 .

[27]  H. Meixner,et al.  On the mechanism of hydrogen sensing with SiO2 modificated high temperature Ga2O3 sensors , 2001 .

[28]  M. Delgado,et al.  Preparation and characterization of mesoporous γ-Ga2O3 , 2000 .

[29]  G. Kresse,et al.  From ultrasoft pseudopotentials to the projector augmented-wave method , 1999 .

[30]  Tsunehiro Tanaka,et al.  Deconvolution Analysis of Ga K-Edge XANES for Quantification of Gallium Coordinations in Oxide Environments , 1998 .

[31]  Burke,et al.  Generalized Gradient Approximation Made Simple. , 1996, Physical review letters.

[32]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[33]  Blöchl,et al.  Projector augmented-wave method. , 1994, Physical review. B, Condensed matter.

[34]  Hafner,et al.  Ab initio molecular dynamics for open-shell transition metals. , 1993, Physical review. B, Condensed matter.

[35]  Rustum Roy,et al.  Polymorphism of Ga2O3 and the System Ga2O3—H2O , 1952 .