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

Sunlight-driven photocatalytic water splitting to generate hydrogen (H-2) is a promising approach for utilizing solar energy. Herein, direct Z-scheme Fe2O3/g-C3N4 photocatalysts are rationally fabricated for H-2 evolution under visible light. The graphitic carbon nitride (g-C3N4) nanosheets obtained by solvent exfoliation of bulk g-C3N4 display modest photocatalytic activity. Strikingly, its photocatalytic performance can be greatly improved by electrostatically assembling with hematite alpha-Fe2O3 nanoplates. With platinum (Pt) as co-catalyst and triethanolamine (TEOA) as hole scavenger, the H-2 generation rate of optimized Fe2O3/g-C3N4 composite with Fe2O3 weight percentage of 10% is about 13-fold that of g-C3N4. 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-C3N4 surface. This rationally synthesized Fe2O3/g-C3N4 composite is expected to have great potentials in solar energy conversation.