Electrospinning preparation of g-C(3)N(4)/Nb(2)O(5) nanofibers heterojunction for enhanced photocatalytic degradation of organic pollutants in water

In this study, graphitic carbon nitride (g-C(3)N(4)) and niobium pentoxide nanofibers (Nb(2)O(5) 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-C(3)N(4)/Nb(2)O(5) heterojunction in which Nb(2)O(5) NFs were tightly attached onto g-C(3)N(4) nanosheets. Compared to pure g-C(3)N(4) and Nb(2)O(5) NFs, the as-prepared g-C(3)N(4)/Nb(2)O(5) 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-C(3)N(4) sheets and Nb(2)O(5) 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(2)(–)) and hole (h(+)) were the major active species contributing to the photocatalytic process. With its high efficacy and ease of preparation, g-C(3)N(4)/Nb(2)O(5) heterojunction has great potentials for applications in treatment of organic pollutants and conversion of solar energy.