In situ synthesis of graphitic-C3N4 nanosheet hybridized N-doped TiO2 nanofibers for efficient photocatalytic H2 production and degradation

Abstract

Graphitic carbon nitride nanosheets (g-C 3 N 4 NSs) hybridized nitrogen doped titanium dioxide (N-TiO 2 ) nanofibers (GCN/NT NFs) have been synthesized in situ via a simple electrospinning process combined with a modified heat-etching method. The prepared GCN/NT NFs were characterized by a variety of methods and their photocatalytic activities were evaluated by hydrogen (H 2 ) production from water splitting and degradation of rhodamine B in aqueous solution. It was found that the GCN/NT NFs have a mesoporous structure, composed of g-C 3 N 4 NSs and N-doped TiO 2 crystallites. The g-C 3 N 4 NSs synthesized after heat-etching were found to be embedded in, and covered, the hybrid NFs to form stable interfaces. The partial decomposition of g-C 3 N 4 releases its nitrogen content which eventually gets doped into the nearby TiO 2 skeleton. The GCN/NT NFs give a high photocatalytic H 2 production rate of 8,931.3 μmol·h −1 ·g −1 in aqueous methanol solution under simulated solar light. Such a highly efficient photocatalytic performance can be ascribed to the combined effects of g-C 3 N 4 NSs and N-doped TiO 2 with enhanced light absorption intensity and improved electron transport ability. Also, the large surface area of the mesoporous NFs minimizes light reflection on the surface and provides more surface-active sites. This work highlights the potential of quasi-one dimensional hybrid materials in the field of solar energy conversion.