Electrospun nanostructured Co3O4/BiVO4 composite films for photoelectrochemical applications

J Colloid Interface Sci. 2019 Mar 15:539:442-447. doi: 10.1016/j.jcis.2018.12.081. Epub 2018 Dec 21.

Abstract

Co3O4/BiVO4 (Co/BiV) based nanostructured photoanode films were fabricated by simple facile electrospinning method and were characterized by a variety of techniques. It was found that the films have web-linked structure, composed of BiVO4 and Co3O4 nanostructures. The photoanode was used for the photoelectrochemical (PEC) degradation of bisphenol-A (BPA) by illumination at 0.25 V vs. SCE assisted by 1 mM peroxymonosulfate (PMS). The removal percentage of BPA was enhanced to 96% for the Co/BiV film that was much better than that of BiVO4 film, which was 48%. The pseudo-first kinetic constants were raised from 0.1126 min-1 to 0.4714 min-1, respectively. The enhanced PEC performance of Co/BiV films can be attributed its p-n heterojunction setup and synergetic contribution of PMS, which efficiently inhibits the recombination of photogenerated electron-hole pairs. The free radicals quenching experiment and electron spin resonance suggested that the major reactive oxygen species were photogenerated holes, superoxide radicals and sulfate radicals. These findings demonstrate that PMS assisted Co/BiV films, are good candidates for PEC application in environmental purification.

Keywords: BiVO(4); Electrospinning; Peroxymonosulfate; Photoelectrochemistry; Thin films.