Synergistic Dual‐Channel Charge Separation in Cr‐TiO2‐x for Solar H2O2 Synthesis
Synergistic Dual‐Channel Charge Separation in Cr‐TiO2‐x for Solar H2O2 Synthesis
研究概述
在超薄TiO2上构筑Cr单原子与氧空位双位点，分别富集空穴和电子，协同驱动两电子水氧化及氧还原制H2O2。原位X射线吸收/发射谱与激发态计算支持电荷分区机制。纯水、无牺牲剂条件下产率764.9 μmol·g⁻¹·h⁻¹，太阳能化学转化效率1.23%。
谱图与表征信息
FIGURE 1 Characterization of the coordination environment of Cr single atoms and the overall structure of Cr-TiO2-x. (a) The AC-HAADF-STEM image with individual Cr atoms highlighted by a yellow frame. The inset displays the local atomic distribution map of Cr-TiO2-x. (b) Fourier transform of EXAFS spectra of Cr-foil, Cr2O3, CrO2, and Cr-TiO2-x. (c) Normalized Cr K-edge XANES spectra of Cr foil, Cr2O3, CrO2, Cr-TiO2, and Cr-TiO2-x. The illustration shows a partial magnified view. (d) EPR spectra of Cr-TiO2-x. (e) O K-edge XAFS spectra of Cr-TiO2 and Cr-TiO2-x. (f) Relation between the relative area of the Kβ′ peak with regard to that of the overall Kβ line and the spin state of the reference compounds (filled black dots), along with the corresponding linear fit of the XES. The inset shows a schematic diagram of the spin state fit of Cr-TiO2-x.