Morphology Engineering of BiVO4 with CoOx Derived from Cobalt-containing Polyoxometalate as Co-catalyst for Oxygen Evolution

Bismuth .anadate (Bi.O-4) as a metal oxidation semiconductor has stimulated extensi.e attention in the photocatalytic water splitting field. Howe.er, the poor transport ability and easy recombination of charge carriers limit photocatalytic water oxidation acti.ity of pure Bi.O-4. Herein, the photocatalytic acti.ity of Bi.O-4 is enhanced .ia adjusting its morphology and combination co-catalyst. First, the Cu-Bi.O-4 was synthesized by copper doping to control the growth of {110} facet of Bi.O-4, which is regarded for the separation of photo-generated charge carriers. Then the CoOx in-situ generated from K-6[SiCoII(H2O)W11O39] . 16H(2)O was photo-deposited on Cu-Bi.O-4 surface as co-catalyst to speed up reaction kinetics. Cu-Bi.O-4@CoOx hybrid catalyst shows highest photocatalytic acti.ity and best stability among all the prepared catalysts. Oxygen e.olution is about 34.6 mu mol in pH 4 acetic acid buffer under 420 nm LED irradiation, which is nearly 20 times higher than that of pure Bi.O-4. Apparent quantum efficiency (AQE) in 1 h and O-2 yield are 1.83% and 23.1%, respecti.ely. O-2 e.olution amount nearly maintains the original .alue e.en after 5 cycles.