Enhancing Water Oxidation Performance of Transition Metal Oxides by Atomically Precise Heteroatom Doping
Enhancing Water Oxidation Performance of Transition Metal Oxides by Atomically Precise Heteroatom Doping
研究概述
研究内容请参见论文原文。
谱图与表征信息
Figure 2. (a) Raman spectra and (b) EXAFS spectra of the as-prepared Fe2O3 and FeCrO3. (c) HRTEM image of FeCrO3. (d) XRD patterns of Fe2O3 and FeCrO3. (e) AC-HAADF-STEM images of FeCrO3. The bright and dark dots are the Fe atom and Cr atoms in FeCrO3, respectively. (f) Zoomed-in view of the blue boxed area in (e); blue and red spheres denote Fe and Cr atoms, respectively. (g) Line profiles of Cr atoms (red boxed), Fe atoms (blue boxed), and Fe and Cr atoms (orange boxed) along the highlighted directions in (f). (h) Surface plot of the red boxed area in (e). (i) HAADF-STEM image and corresponding elemental maps of FeCrO3.
Figure 4. (a) Hirshfeld population analysis of Fe and Cr in Cr2O3, Fe2O3, and FeCrO3. (b) Fe 2p XPS spectra of Fe2O3 and FeCrO3. The red, blue, and orange lines are the Fe2+ peaks, Fe3+ peaks, and satellite peaks, respectively, while the gray lines are the sum-up Fe 2p peaks. (c) XANES results for Fe2O3 and FeCrO3. The inset is a zoomed-in view of the boxed area. (d) Cyclic voltammograms of Fe2O3 and FeCrO3. (e) Potential-dependent absorption intensities of interfacial water measured by an in situ Raman test in the 1 M KOH electrolyte for FeCrO3. The overall spectra are deconvoluted into three components, i.e., 4HB-H2O, 2HB-H2O, and K−H2O, which are shown in blue, orange, and red, respectively. (f) The population of different types of water on FeCrO3 derived from (e). (g) PDOS and the d band center of Fe active sites in FeCrO3 and Fe2O3. (h) Gibbs free energy diagrams of the kinetics of the OER intermediates over Fe2O3 and FeCrO3 at applied potentials (U) of 0 and 1.23 V. (i) Schematic diagram illustrating the enhancement mechanism of the activity of the OER on FeCrO3.