High-efficiency photocatalytic water splitting by a N-doped porous g-C3N4 nanosheet polymer photocatalyst derived from urea and N,N-dimethylformamide†
In this work, layered N-doped graphitic carbon nitride (g-C3N4) porous nanosheets were successfully prepared by mixing the precursor of N,N-dimethylformamide (DMF) and urea through a simple one-step thermal copolymerization method. The doped-N plays a significant role in modifying the chemical and electronic structure of g-C3N4, which can decrease the migration pathway of the charges and suppress the recombination of the photogenerated carriers based on experimental characterization data and the density functional theory (DFT) calculation results. Through nanostructure engineering design, the as-prepared photocatalyst exhibits promoted specific surface area and enhanced light absorption capacity. Consequently, the as-prepared N-doped porous g-C3N4 nanosheets yield about 14 times higher H2 evolution rate than pristine g-C3N4 nanosheets under visible light irradiation. The present study provides a simple and convenient method of nanostructure engineering for the synthesis of modified g-C3N4 with excellent photocatalytic activity to meet the sustainable demand of energy.