Fig. 4: Cross-sectional HRTEM image and EDX analysis of BiVO4/TiO2 and BiVO4/PEI/TiO2.
From: A hole-selective hybrid TiO2 layer for stable and low-cost photoanodes in solar water oxidation
a–d Cross-sectional image of BiVO4/TiO2 (a) and elemental mapping of Bi, Ti, and O (b–d), respectively. e–h Cross-sectional image of BiVO4/PEI/TiO2 (e) and the corresponding mapping elements (f–h). White arrows indicate the interfacial PEI layer between BiVO4 and TiO2.
