Novel phosphidated MoS2 nanosheets modified CdS semiconductor for an efficient photocatalytic H2 evolution

In this work, the rational design of phosphidated MoS2 (P-MoS2) nanosheets decorated on CdS nanoparticles (NPs) is reported. First, the P-MoS2 nanosheets were obtained by the phosphidation of MoS2 at 300 degrees C and using NaH2PO2 as P source. Then, the coupling of P-MoS2 nanosheets with CdS NPs was completed by a hydrothermal treatment. The photocatalytic performance of resulted composite was evaluated by evolution of H-2 from water splitting. The experimental results revealed that the P-MoS2/CdS composite containing 20% P-MoS2 exhibited an optimum H-2 evolution rate as high as 58.9 mu mol h(-1), which was 2.9 and 2.3 times higher than that of the pristine CdS (20.5 mu mol h(-1)) and 0.2MoS(2)/CdS (26.1 mu mol h(-1)), respectively. The improved activity of P-MoS2/CdS composite compared to MoS2/CdS can be ascribed to (i) its enhanced visible-light absorption, (ii) its efficient electron-hole separation resulting from the enhanced conductivity of P-MoS2, the positive conduction band potential of P-MoS2 in comparison with that of MoS2, and (iii) the more exposed active sites on P-MoS2 resulting from the enlarged interlayer spacing. This work may open up a new avenue to explore other hybrid co-catalysts to enhance the charge separation and thus the photocatalytic H-2-evolution performance of semiconductors.