Enhanced photocatalytic H2 production of flower-like MoS2@Ag2S photocatalysts with matched band structures

Abstract

The flower-like MoS2@Ag2S (MS@AS) photocatalyst was synthesized by the hydrothermal and ion exchange reactions. Results of SEM, TEM, elemental line scan profiles, and XPS analysis revealed that Ag2S nanoparticles were attached to flower-like MoS2. Raman spectra confirm that MoS2 (MS) and MoS2@Ag2S (MS@AS) photocatalysts are hybrid phases of 1 T-MoS2 and 2H-MoS2. Compared with pristine MoS2, the shifts of XPS Mo3d and S2s peaks of MS@AS photocatalyst indicate the interaction between MoS2 and Ag2S (or Ag). The band structure of the photocatalyst is proposed based on the UPS spectrum and Tauc plot of MoS2 and Ag2S. The H2 production efficiency of MoS2@Ag2S photocatalyst reaches 3516 μmol·g−1·h−1, better than that of MoS2. The MoS2@Ag2S photocatalyst exhibits a S-scheme band structure, which can facilitate electron-hole separation and improves photocatalytic H2 production activity.