Self‐standing Janus nanofiber heterostructure photocatalyst with hydrogen production and degradation of methylene blue

Abstract

AbstractA highly efficient, stable, easily recyclable carbon‐based [g‐C3N4/C]//[TiO2/C] Janus nanofibers heterostructure photocatalyst (gT‐JNHP) was first designed and constructed through the combination of conjugative electro‐spinning with subsequent calcination procedure. gT‐JNHP with novel Janus structure consists of two sides: one side is g‐C3N4/C nanofiber that absorbs visible light (VL), and the other side is TiO2/C nanofiber that can capture ultraviolet light (UL), and the two strands of nanofibers are tightly combined together to form the unique heterostructure Janus nanofiber, which can make full use of sunlight (SL). gT‐JNHP presents better remarkably boosted photocatalytic performance in comparison with the counterpart g‐C3N4/C, TiO2/C, or their mechanical mixture, and the degradation efficiencies of methylene blue in gT‐JNHP‐2, respectively, are 95.1% (160 min) and 98.6% (140 min), as well as hydrogen evolution rates reach up to 12.40 and 16.72 mmol h–1 g–1 under VL and simulated SL, respectively, thereby displaying the excellent dual functions of high‐efficient hydrogen release and removal of organic contaminant. The outstanding photocatalytic property is ascribed to the joint effect among the unique Janus‐typed heterostructure, catalyst components, and electrically conductive carbon fiber, achieving close contact between the interfaces, effective separation of photo‐excited carriers, strong light capture ability, and many more exposed active sites, etc. Feasible photocatalytic mechanisms are advanced. Moreover, gT‐JNHP owns the characteristics of flexible self‐standing, easy recycling, and superb durability. The constructing mechanisms of Janus nanofibers and gT‐JNHP are discussed in detail, and the novel fabricating techniques are established. The designing idea and construction techniques adopted in this paper are popularized for research and development of other peculiar uni‐dimensional dual‐functional nanofibrous photocatalysts.