Synthesis of rhodium phosphide cocatalyst and remarkably enhanced photocatalytic hydrogen evolution over CdS under visible light radiation

Rhodium phosphide (RhP) is utilized as a novel cocatalyst for CdS photocatalyst. The RhP cocatalyst greatly improves the photocatalytic performance, reusability and lifetime of CdS for H2generation from splitting water under visible light illumination (λ > 420 nm). The optimal compound, 20 wt% RhP/CdS, produces the highest hydrogen amount of 325.4 μmol/mg after 10 h, which is about 196,024 times that of pure CdS. The apparent quantum yield of H2evolution over the 20 wt% RhP/CdS after 100 h reaches 34.3%. Ultraviolet photoelectron spectrometer, fluorescence spectroscopy and photocurrent show that the RhP with strong electron attraction ability can accelerate the separation of photo-excited electron-hole pairs, which is responsible for the enhanced hydrogen evolution ability of CdS. © 2016 Elsevier B.V.