Nitrogen Vacancy-Promoted Photocatalytic Activity of Graphitic Carbon Nitride

Vacancy defects can play an important role in modifying the electronic structure and the properties of photoexcited charge carriers and consequently the photocatalytic activity of semiconductor photocatalysts. By controlling the polycondensation temperature of a dicyandiamide precursor in the preparation of graphitic carbon nitride (g-C3N4), we introduced nitrogen vacancies in the framework of g-C3N4. These vacancies exert remarkable effects on modifying the electronic structure of g-C3N4 as shown in UV–visible absorption spectra and valence band spectra. Steady and time-resolved fluorescence emission spectra show that, due to the existence of abundant nitrogen vacancies, the intrinsic radiative recombination…