Spinel-type ferrites decorated ZnO for enhanced photoelectrochemical water splitting

Among numerous semiconductor photoanodes, ZnO has been widely touted for its high electron mobility in the realm of Photoelectrochemical water splitting. However, some inevitable problems have limited its widening applications, such as narrow light photoresponse range and many surface defects. To this end, we first time demonstrate a novel strategy for CoFe2O4/ZnO and NiFe2O4/ZnO photoanodes by uncomplicated and inexpensive spin-coating and calcination stratagem. The optimal nanocomposite photoanodes showed excellent photocurrent density (2.3 folds higher than bare ZnO photoanode) and a negatively shifted onset potential of 75 mV. Moreover, due to the construction of Type-II heterojunction, the surface trap state of ZnO is reduced, the separation of photoproduced carriers is enhanced, the active sites are increased, and the interface reaction dynamics are accelerated.

Automated summary

In this study, a novel strategy for CoFe2O4/ZnO and NiFe2O4/ZnO photoanodes was demonstrated using a simple and inexpensive approach. The resulting nanocomposite photoanodes showed improved photocurrent density and a negatively shifted onset potential, addressing some limitations of bare ZnO photoanodes.