Photocatalytic overall water splitting hydrogen evolution enhancement of ZnO nanoarrays/LaCrO3 film heterojunction via HER/OER synergism of CoP/FTO

Abstract

The synergism of HER/OER would be an important issue for achieving overall water splitting. Herein, the CoP/FTO synergetic modified ZnO/LaCrO3 nanoarrays heterojunction is fabricated via a continuous annealing-hydrothermal-electrodeposition method. Evaluated by the photocatalytic performance, the CoP-ZnO-LaCrO3-FTO exhibits an enhanced HER performance of ∼30 folds than single LaCrO3 and ∼40 folds than single ZnO, and achieves a decent overall water splitting performance of ∼2418.1(H2)/1185.9(O2) μmol∙m−2∙h−1, which can be mainly ascribed to the synergism of HER/OER and formation of nanoarrays heterojunction. There, the CoP obtains sufficient HER active sites can accelerate the photo-generated electrons diffusing into water for HER, the FTO with hole­related species can promote OER, and the ZnO/LaCrO3 nanoarrays heterojunction can improve carrier efficiency and solar efficiency. Additionally, the nanoarrays heterojunction with high physical stability and photocorrosion inhibition can maintain good stability during photocatalytic process.