Constructing 2D/2D Fe₂O₃/g‐C₃N₄ Direct Z‐Scheme Photocatalysts with Enhanced H₂ Generation Performance

Abstract

Sunlight‐driven photocatalytic water splitting to generate hydrogen (H 2 ) is a promising approach for utilizing solar energy. Herein, direct Z‐scheme Fe 2 O 3 /g‐C 3 N 4 photocatalysts are rationally fabricated for H 2 evolution under visible light. The graphitic carbon nitride (g‐C 3 N 4 ) nanosheets obtained by solvent exfoliation of bulk g‐C 3 N 4 display modest photocatalytic activity. Strikingly, its photocatalytic performance can be greatly improved by electrostatically assembling with hematite α‐Fe 2 O 3 nanoplates. With platinum (Pt) as co‐catalyst and triethanolamine (TEOA) as hole scavenger, the H 2 generation rate of optimized Fe 2 O 3 /g‐C 3 N 4 composite with Fe 2 O 3 weight percentage of 10% is about 13‐fold that of g‐C 3 N 4 . Based on the enhanced photocatalytic performance and slower time‐resolved photoluminescence decay, Z‐scheme charge transfer process is accepted for running this photocatalytic system, which is further evidenced by selective photo‐deposition of Pt nanoparticles on the g‐C 3 N 4 surface. This rationally synthesized Fe 2 O 3 /g‐C 3 N 4 composite is expected to have great potentials in solar energy conversation.