Graphdiyne/Ag₂Mo₂O₇ S‐Scheme Heterojunction for Photocatalytic Hydrogen Production Promoted with Efficient Photogenerated Carriers Separation

Abstract

: Inhibiting the recombination of photoexcited hole‐electron pairs is the crucial for efficient hydrogen‐producing by photocatalytic water splitting under visible light. Although Ag2Mo2O7 has excellent photoelectrochemical properties and strong morphological plasticity, its hydrogen‐producing activity is inhibited due to its low separation efficiency of photogenerated carriers and small photoresponse range. Therefore, we prepared GDY (graphdiyne) using alkynyl anions and compounded GDY with Ag2Mo2O7 by electrostatic self‐assembly. The hydrogen‐producing capacity of the composite catalyst GDY/Ag2Mo2O7 reached up to 8156.6 μmol·g‐1·h‐1, what’s more, the photocatalytic hydrogen‐producing capacity of Ag2Mo2O7, GDY and GDY/Ag2Mo2O7 were investigated by in‐situ XPS, electrochemical testing, fluorescence analysis and DFT calculation. The consequences display that the addition of GDY increases the visible light absorption intensity of Ag2Mo2O7, and the composite catalyst GDY/Ag2Mo2O7 shows the best fluorescence quenching effect and the highest photocurrent response intensity. In the final analysis, the preeminent photocatalytic hydrogen‐producing performance of the composition GDY/Ag2Mo2O7 is due to the establishment of type S heterojunction, the migration rate of photogenerated electrons is increased and the migration path is shortened, consequently plentiful electrons is involved in the hydrogen‐producing reaction therewith increase the amount of hydrogen‐producing of the catalyst. This contributes a practical tactics to effectively enhance the capacity of photocatalytic hydrogen‐producing by solving the problem of serious recombination of photogenerated carriers.This article is protected by copyright. All rights reserved.