Continuous g-C 3 N 4 layer-coated porous TiO 2 fibers with enhanced photocatalytic activity toward H 2 evolution and dye degradation.

TiO 2 /g-C 3 N 4 composite photocatalysts with various merits, including low-cost, non-toxic, and environment friendliness, have potential application for producing clean energy and removing organic pollutants to deal with the global energy shortage and environmental contamination. Coating a continuous g-C 3 N 4 layer on TiO 2 fibers to form a core/shell structure that could improve the separation and transit efficiency of photo-induced carriers in photocatalytic reactions is still a challenge. In this work, porous TiO 2 (P-TiO 2 )@g-C 3 N 4 fibers were prepared by a hard template-assisted electrospinning method together with the g-C 3 N 4 precursor in an immersing and calcination process. The continuous g-C 3 N 4 layer was fully packed around the P-TiO 2 fibers tightly to form a TiO 2 @g-C 3 N 4 core/shell composite with a strong TiO 2 /g-C 3 N 4 heterojunction, which greatly enhanced the separation efficiency of photo-induced electrons and holes. Moreover, the great length-diameter ratio configuration of the fiber catalyst was favorable for the recycling of the catalyst. The P-TiO 2 @g-C 3 N 4 core/shell composite exhibited a significantly enhanced photocatalytic performance both in H 2 generation and dye degradation reactions under visible light irradiation, owing to the specific P-TiO 2 @g-C 3 N 4 core/shell structure and the high-quality TiO 2 /g-C 3 N 4 heterojunction in the photocatalyst. This work offers a promising strategy to produce photocatalysts with high efficiency in visible light through a rational structure design.