Highly efficient photoelectrocatalytic degradation of cefotaxime sodium on the MoSe2/TiO2 nanotubes photoanode with abundant oxygen vacancies

Abstract

Novel multifunctional photoanode on basis of MoSe2 nanoparticles modified TiO2 nanotubes(denoted as MoSe2/TiO2 NTs) were successfully prepared by facile electrochemical methods namely anodization followed by cyclic voltammetry method using titanium foil as substrate. Compared to TiO2 NTs, the MoSe2/TiO2 NTs display excellent photoeletric properties, including more abundant surface oxygen vacancies, enhanced visible-light absorption, improved photocurrent response, reduced fluorescence intensity and decreased charge transfer resistance. These enhancements should be attributed to efficient spatial separation and rapid transfer of photo-induced electrons and holes on the intimate contact interface between MoSe2 nanoparticles and TiO2 NTs. In the photo-electric synergistic catalytic system, the as-prepared MoSe2/TiO2 NTs play double roles as both photoanode and catalyst. Under simulated solar light illumination, the MoSe2/TiO2 NTs photoanode shows superior photoelectrocatalytic activity in the degradation of cefotaxime sodium at low applied bias voltage. Moreover, a possible mechanism of the transfer pathway of photo-induced charge carriers on the MoSe2/TiO2 NTs photoanode is proposed based on the synergistic effect of surface oxygen vacancies and direct Z-scheme heterojunction.