Fabrication of alveolate g-C3N4 with nitrogen vacancies via cobalt introduction for efficient photocatalytic hydrogen evolution

Photocatalytic hydrogen evolution is a promising method for converting solar energy into chemical energy. Herein, on the basis of graphitic carbon nitride (g-C3N4) material with alveolate structure prepared via the hard template method, transition-metal cobalt oxide nanoparticles were reasonably introduced, and a highly efficient cobalt oxide composite alveolate g-C3N4 (ACN) photocatalyst was successfully prepared. A series of test methods were used to characterize the structural properties of the prepared samples systematically, and the photocatalytic activity of the catalysts in photocatalytic hydrogen evolution was explored. The composite materials have excellent photocatalytic performance mainly because the synergistic effect of the alveolate structure of ACN provides multiple scattering effects; nitrogen vacancies serves as the centers of photogenerated carrier separation; and cobalt oxides accelerates electron transfer. This study provides a new idea for the design of g-C3N4-based photocatalysts with wide light responses and simple structures. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.