Enhancing the photoelectrochemical performance of BiVO4 by decorating only its (040) facet with self-assembled Ag@AgCl QDs

Decorating a host semiconductor with quantum dots (QDs) is an important strategy for optimizing the separation efficiency and transfer of photogenerated charge carriers. In this work, we designed a heterojunction photoelectrocatalyst in which the (040) facet of BiVO4 was decorated with self-assembled Ag@AgCl QDs (Ag@AgCl/040BiVO4). In this photocatalyst, photogenerated charge carriers are efficiently separated using a Z-scheme approach. A facile oil-in-water self-assembly method was employed to generate the composite photocatalyst, which was then characterized via XRD, XPS, SEM, TEM, etc. The results of this characterization indicated that the Ag@AgCl QDs were approximately 5 nm in size and were well dispersed across the (040) crystal facet of BiVO4. PEC measurements indicated that the efficiency of electron-hole separation was enhanced when the BiVO4 was decorated with Ag@AgCl QDs on just one of its facets (040) rather than across all of its surface. An attempt was also made to elucidate the mechanism of interfacial charge transfer in the Ag@AgCl/040BiVO4 system. Decorating a specific crystal facet (040) of BiVO4 with Ag@AgCl QDs was found to facilitate the spatial separation of photogenerated charge carriers and to enhance the redox ability of the system.