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Bismuth vanadate (BiVO 4 ) as a metal oxidation semiconductor has stimulated extensive attention in the photocatalytic water splitting field. However, the poor transport ability and easy recombination of charge carriers limit photocatalytic water oxidation activity of pure BiVO 4 . Herein, the photocatalytic activity of BiVO 4 is enhanced via adjusting its morphology and combination co-catalyst. First, the Cu-BiVO 4 was synthesized by copper doping to control the growth of {110} facet of BiVO 4 , which is regarded for the separation of photo-generated charge carriers. Then the CoO x in-situ generated from K 6 [SiCo II (H 2 O)W 11 O 39 ] • 16H 2 O was photo-deposited on Cu-BiVO 4 surface as co-catalyst to speed up reaction kinetics. Cu-BiVO 4 @CoO x hybrid catalyst shows highest photocatalytic activity and best stability among all the prepared catalysts. Oxygen evolution is about 34.6 μmol in pH 4 acetic acid buffer under 420 nm LED irradiation, which is nearly 20 times higher than that of pure BiVO 4 . Apparent quantum efficiency (AQE) in 1 h and O 2 yield are 1.83% and 23.1%, respectively. O 2 evolution amount nearly maintains the original value even after 5 cycles.

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Polymer–crystal composite particles formed by crystals coated with binders are widely used in the fields of medicine, energy, the chemical industry, and civil engineering. Binder content is an important factor in determining the mechanical behavior of composite particles. Therefore, this study aimed to investigate the underlying effect of binder coatings in the fracture micromechanics of polymer–crystal composite particles using the discrete element method (DEM). To achieve this objective, realistic particle and crystal shapes were first obtained and reconstructed based on X-ray micro-computed tomography (μCT) scanning and scanning electron microscope (SEM) images. A series of single particle crushing tests and DEM simulations were conducted on real and reconstructed polymer–crystal composite particles, respectively. Based on the experimental and DEM results, the effect of binder coatings on the crushing strength and crushing patterns of polymer–crystal composite particles was measured. Moreover, the micromechanics of the development and distribution of microcracks was further investigated to reveal the mechanism by which binder coatings affect polymer–crystal composite particles.

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