Photoinduced anisotropic distortion as the electron trapping site of tungsten trioxide by ultrafast W L1-edge X-ray absorption spectroscopy with full potential multiple scattering calculations. Issue 5 (16th April 2019)

• Record Type: Journal Article
• Authors: Koide, Akihiro; Uemura, Yohei; Kido, Daiki; Wakisaka, Yuki; Takakusagi, Satoru; Ohtani, Bunsho; Niwa, Yasuhiro; Nozawa, Shunsuke; Ichiyanagi, Kohei; Fukaya, Ryo; Adachi, Shin-ichi; Katayama, Tetsuo; Togashi, Tadashi; Owada, Shigeki; Yabashi, Makina; Yamamoto, Yusaku; Katayama, Misaki; Hatada, Keisuke; Yokoyama, Toshihiko; Asakura, Kiyotaka
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 5(2020)
• Page Start: 2615
• Page End: 2621
• Publication Date: 2019-04-16
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp01332f
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Ultrafast XANES spectra and full-potential multiple scattering reveal the anisotropic structure change of photoexcited WO3 . Abstract : Understanding the excited state of photocatalysts is significant to improve their activity for water splitting reaction. X-ray absorption fine structure (XAFS) spectroscopy in X-ray free electron lasers (XFEL) is a powerful method to address dynamic changes in electronic states and structures of photocatalysts in the excited state in ultrafast short time scales. The ultrafast atomic-scale local structural change in photoexcited WO3 was observed by W L1 edge XAFS spectroscopy using an XFEL. An anisotropic local distortion around the W atom could reproduce well the spectral features at a delay time of 100 ps after photoexcitation based on full potential multiple scattering calculations. The distortion involved the movement of W to shrink the shortest W–O bonds and elongate the longest one. The movement of the W atom could be explained by the filling of the d xy and d zx orbitals, which were originally located at the bottom of the conduction band with photoexcited electrons.