Effect of Laser Energy Density on Photophysical and Photocatalytic Properties of BiVO₄ Single‐Crystal Thin Film

Abstract

The single‐crystal thin films are more conducive to an in‐depth understanding of the intrinsic mechanism of the photocatalytic reaction. Herein, the BiVO4 single‐crystal thin‐films are prepared on the (001)‐oriented yttrium‐stabilized zirconia (YSZ (001)) substrates using pulsed laser deposition at a different laser energy density of 42–102 mJ cm−2. The results of X‐Ray diffraction reveal that the samples all have a monoclinic scheelite structure and grow epitaxially along the b‐axis orientation. With the increase in laser power density, the peak positions of Bi 4f, V 2p, and O 1s in the results of the X‐Ray photoelectron spectroscopy shift toward higher binding energies, and the visible light absorption ability of BiVO4 films also weakens. The BiVO4 film at a laser energy density of 42 mJ cm−2 exhibits high photocatalytic activity and good stability in the photocatalytic degradation of Rhodamine B (RhB). The trapping experiments also prove that holes (h+) and hydroxyl radicals (·OH) are the main active species.