Defective High-Crystallinity g-C<sub>3</sub>N<sub>4</sub> Heterostructures by Double-End Modulation for Photocatalysis
Tao Jiang, Zhaowu Wang, Guo Wei, Shixin Wu, Liqiu Huang, Derun Li, Xuefeng Ruan, Yichao Liu, Changzhong Jiang, Feng Ren
Abstract
Photocatalytic overall water splitting is difficult due to the limitations of band structure, solar absorption efficiency, and carrier recombination. Rich nitrogen vacancies containing g-C 3 N 4 nanosheets were prepared by spark plasma sintering. By modifying highly crystalline graphitic carbon nitride (g-C 3 N 4 ) with rich nitrogen vacancies as the hydrogen- and oxygen-producing ends and building a Z-scheme heterostructure, overall water splitting can be achieved. Hydrogen and oxygen evolution rates (λ > 320 nm) of 1.51 and 0.75 mmol g –1 h –1 with the reported highest solar-to-hydrogen efficiency of 1.39% for pure g-C 3 N 4 catalyst with cocatalysts under an AM1.5G filter (100 mW cm –2 ) are reached. The double-ended modulation method improves the overall photocatalytic overall water splitting efficiency of high-crystallinity defect-rich g-C 3 N 4 .