Porous Graphitic Carbon Nitride Nanosheets by Pre-polymerization for Enhanced Hydrogen Evolution from Water Splitting under Solar Light

Abstract

A facile and green method was developed to fabricate porous graphitic carbon nitride (g-C3N4) nanosheets by simple pre-polymerizing melamine. Porous structures were formed in polymerized g-C3N4 at 350∘C for 2h, which greatly enhanced the specifi  surface area and pore volume, resulting in superior photocatalytic evolution. The hydrogen evolution rate was 11.2 higher than that of bulk g-C3N4 under visible light. The porous structure not only provided abundant active catalytic sites and cross-plane diffusion channels to facilitate the charge and mass transportation, but also promoted the charge separation in the photocatalytic reaction. This g-C3N4 is suitable for mass-production to generate hydrogen from water splitting.


Keywords: graphitic carbon nitride, photocatalytic, porous structures, prepolymerization, hydrogen evolution from water splitting

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