Significant Enhancement of Visible-Light-Driven Hydrogen Evolution by Structure Regulation of Carbon Nitrides

• Published in: ACS nano Vol. 12; no. 6; pp. 5221 - 5227
• Main Authors: Han, Qing, Cheng, Zhihua, Wang, Bing, Zhang, Huimin, Qu, Liangti
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 26.06.2018
• Subjects: antisolvent growth; defect-rich amorphous carbon nitride; photocatalysis; visible-light hydrogen evolution; size-reduced urea
• ISSN: 1936-0851; 1936-086X; 1936-086X
• DOI: 10.1021/acsnano.7b08100

Photocatalytic water splitting for hydrogen evolution by utilizing solar energy has a great significance for high-density solar energy storage and environmental sustainability. Here, a defect-rich amorphous carbon nitride (DACN) photocatalyst has been synthesized by simply direct calcination of the rationally size-reduced urea crystals. The introduction of nitrogen vacancies combined with disordered structure cause a broad visible-light-reponsive range, countless lateral edge/exposed surface bonding sites, and quenched radiative recombination, suggesting that this DACN enhances photocatalytic activity for hydrogen production. A record high hydrogen evolution rate of 37,680 μmol h–1 g–1 under visible-light irradiation and an extraordinary apparent quantum efficiency of 34.4% at 400 nm were achieved, higher than most of the existing graphitic carbon nitride-based photocatalysts.