Controllable synthesis of Titania‐Supported Bismuth Oxyiodide Heterostructured Nanofibers with Highly Exposed (1 1 0) Bismuth Oxyiodide Facets for Enhanced Photocatalytic Activity

The bismuth oxyiodide/titanium dioxide (BiOI/TiO2) heterostructured nanofibers with exposed (110) BiOI facets were synthesized via electrospinning and hydrothermal methods. The BiOI/TiO2 heterostructures with exposed (110) BiOI facets exhibited much enhanced photoreactivity, in which the methylene blue and phenol degradation rate rises more than 2 times and the photocurrent density is 12 times as high as that of BiOI with exposed (110) facets. The electron spin resonance (ESR) spectroscopy indicated that the hydroxyl radicals and superoxide radicals could be generated by BiOI/TiO2 heterostructures with exposed (110) BiOI facets. Based on the experimental results, the enhancement of photocatalytic activity could be attributed to the strong oxidization by hydroxyl radicals, enlarged band gap, lowered valence band (VB) position as well as the suppressed recombination of photoinduced electron-hole pairs by the manipulation of heterostructures with exposed (110) BiOI reactive facets.