Photodeposition of highly dispersed MoS2 nanosheets on CdS nanorods with enhanced photocatalytic activity for reduction of p-nitroaniline to p-phenylenediamine

Abstract

So far, the significant effect of different assembly methods on the microstructures and photocatalytic properties of MoS2/CdS nanocomposite photocatalysts has rarely been reported. In the study, single-crystalline CdS nanorods (NRs) were prepared by a solvothermal method. MoS2 cocatalyst was decorated on the CdS NRs to obtain MoS2/CdS-PD and MoS2/CdS-HT photocatalysts by an in situ photodeposition (PD) technique and a hydrothermal (HT) method, respectively. Under visible light irradiation, the photocatalytic activity of MoS2/CdS-PD and MoS2/CdS-HT for reduction of p-nitroaniline (p-NA) to p-phenylenediamine (p-PDA) was comparatively studied. Results indicate: i) When MoS2 was attached on CdS NRs by the in situ PD, ultrathin MoS2 nanosheets could be uniformly and tightly tethered to CdS NRs to form core-shell MoS2/CdS-PD composite, whereas MoS2 nanosheets were aggregated to form stacked multilayered structure and loosely coupled to CdS NRs to produce non-core-shell MoS2/CdS-HT by the HT method. ii) MoS2/CdS-PD exhibits higher photocatalytic efficiency for p-NA reduction than MoS2/CdS-HT, which can be ascribed to the fact that the interfacial contact between MoS2 and CdS is more intimate and the electron transfer from CdS to MoS2 is more efficient in MoS2/CdS-PD than that in MoS2/CdS-HT.