Fabrication of core-shell BiVO4@Fe2O3 heterojunctions for realizing photocatalytic hydrogen evolution via conduction band elevation

Core-shell heterostructured BiVO 4 @Fe 2 O 3 photocatalysts are fabricated through a facile solution combustion and in-situ precipitation methods. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) images verify their core-shell structure. X-ray photoelectron spectroscopy (XPS) results indicate there are interaction between BiVO 4 and Fe 2 O 3 , confirming the formation of heterojunction. Mott–Schottky measurements exhibit that hybridizing with Fe 2 O 3 makes the conduction band of BiVO 4 to be shifted up by 1.05 V from 0.21 to −0.84 V, which endows BiVO 4 to be effective for photocatalytic H 2 generation. Meanwhile, photoluminescence spectra show that the heterosturcture decreases the recombination efficiency of photo-induced electrons and holes. Hydrogen experiments indicate that BiVO 4 @Fe 2 O 3 composite containing 10 wt% Fe 2 O 3 has the highest catalytic activity.