title: Catalytic activities of noble metal atoms on WO3 (001): nitric oxide adsorption.
abstract: Using first-principles density functional theory calculations within the generalized gradient approximation, we investigate the adsorption of NO molecule on a clean WO3(001) surface as well as on the noble metal atom (Cu, Ag, and Au)-deposited WO3(001) surfaces. We find that on a clean WO3 (001) surface, the NO molecule binds to the W atom with an adsorption energy (E ads) of -0.48 eV. On the Cu- and Ag-deposited WO3(001) surface where such noble metal atoms prefer to adsorb on the hollow site, the NO molecule also binds to the W atom with E ads = -1.69 and -1.41 eV, respectively. This relatively stronger bonding of NO to the W atom is found to be associated with the larger charge transfer of 0.43 e (Cu) and 0.33 e (Ag) from the surface to adsorbed NO. However, unlike the cases of Cu-WO3(001) and Ag-WO3(001), Au atoms prefer to adsorb on the top of W atom. On such an Au-WO3(001) complex, the NO molecule is found to form a bond to the Au atom with E ads = -1.32 eV. Because of a large electronegativity of Au atom, the adsorbed NO molecule captures the less electrons (0.04 e) from the surface compared to the Cu and Ag catalysts. Our findings not only provide useful information about the NO adsorption on a clean WO3(001) surface as well as on the noble metal atoms deposited WO3(001) surfaces but also shed light on a higher sensitive WO3 sensor for NO detection employing noble metal catalysts.
authors: International Laboratory for Quantum Functional Materials of Henan, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, 450001 China ; School of Mechanical and Electrical Engineering, Henan Institute of Science and Technology, Xinxiang, 453003 China.
authors: Xiaoyan
authors: X
authors: Ren
authors: International Laboratory for Quantum Functional Materials of Henan, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, 450001 China.
authors: Shuai
authors: S
authors: Zhang
authors: International Laboratory for Quantum Functional Materials of Henan, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, 450001 China ; Center for Clean Energy and Quantum Structures, Zhengzhou University, Zhengzhou, 45001 China.
authors: Chong
authors: C
authors: Li
authors: International Laboratory for Quantum Functional Materials of Henan, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, 450001 China ; Center for Clean Energy and Quantum Structures, Zhengzhou University, Zhengzhou, 45001 China.
authors: Shunfang
authors: S
authors: Li
authors: International Laboratory for Quantum Functional Materials of Henan, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, 450001 China ; Center for Clean Energy and Quantum Structures, Zhengzhou University, Zhengzhou, 45001 China.
authors: Yu
authors: Y
authors: Jia
authors: Department of Physics and Research Institute for Natural Sciences, Hanyang University, 17 Haengdang-Dong, Seongdong-Ku, Seoul, 133-791 Korea.
authors: Jun-Hyung
authors: JH
authors: Cho
keywords: Bond length; Catalytic; Charge transfer; Surface