Electrospinning preparation of g-CN/NbO nanofibers heterojunction for enhanced photocatalytic degradation of organic pollutants in water.

In this study, graphitic carbon nitride (g-CN) and niobium pentoxide nanofibers (NbO NFs) heterojunction was prepared by means of a direct electrospinning approach combined with calcination process. The characterizations confirmed a well-defined morphology of the g-CN/NbO heterojunction in which NbO NFs were tightly attached onto g-CN nanosheets. Compared to pure g-CN and NbO NFs, the as-prepared g-CN/NbO heterojunction exhibited remarkably enhanced photocatalytic activity for degradation of rhodamine B and phenol under visible light irradiation. The enhanced catalytic activity was attributed predominantly to the synergistic effect between g-CN sheets and NbO NFs, which promoted the transferring of carriers and prohibited their recombination, confirmed by the measurement of transient photocurrent responses and photoluminescence spectra. In addition, the active species trapping experiments indicated that superoxide radical anion (·O) and hole (h) were the major active species contributing to the photocatalytic process. With its high efficacy and ease of preparation, g-CN/NbO heterojunction has great potentials for applications in treatment of organic pollutants and conversion of solar energy.