Ag K- and L3-edge XAFS study on Ag species in Ag/Ga2O3 photocatalysts

16th International Conference on X-ray Absorption Fine Structure

Yamamoto, M.^1 ; Yoshida, T.^2,3 ; Yamamoto, N.^1 ; Nomoto, T.^4 ; Yamamoto, A.^5,6 ; Yoshida, H.^5,6 ; Yagi, S.^3

Graduate School of Engineering, Nagoya University, Nagoya

464-8603, Japan^1

Advanced Research Institute for Natural Science and Technology, Osaka City University, Osaka

558-8585, Japan^2

EcoTopia Science Institute, Nagoya University, Nagoya

464-8603, Japan^3

Aichi Synchrotron Radiation Center, Seto

489-0965, Japan^4

Graduate School of Human and Environmental Studies, Kyoto University, Kyoto

606-8501, Japan^5

Element Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto

615-8520, Japan^6

关键词: Chemical state;    High loadings;    High photocatalytic activities;    Interface structures;    Loading amount;    Metal cluster;    Photocatalytic activities;    Preparation method;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012074/pdf
DOI  :  10.1088/1742-6596/712/1/012074

来源: IOP

【 摘 要 】

Ag loaded Ga2O3(Ag/Ga2O3) shows photocatalytic activity for reduction of CO2with water. Ag L3-edge XANES and K-edge EXAFS spectra were measured for various Ag/Ga2O3samples, which suggested that structural and chemical states of Ag species varied with the loading amount of Ag and the preparation method. The Ag species were metallic Ag particles with an AgGaO2-like interface structure in the sample with high loading amount of Ag while predominantly Ag metal clusters in the sample with low loading amount of Ag. The XANES feature just above the edge represented the interaction between the Ag species and the Ga2O3surface, showing that the Ag metal clusters had more electrons in the d-orbitals by interacting with the Ga2O3surface, which would contribute the high photocatalytic activity.