Construction of immobilized 0D/1D heterostructure photocatalyst Au/CuS/CdS/TiO2 NBs with enhanced photocatalytic activity towards moxifloxacin degradation

Strong absorption in a wide wavelength range and effective charge separation are main factors for improving photocatalytic activity of semiconductor photocatalysts. Herein, immobilized zero-dimensional/one-dimensional (0D/1D) Au/CuS/CdS/TiO 2 nanobelts (Au/CuS/CdS/TiO 2 NBs) heterostructure photocatalyst with innovative morphology and appropriate band-gap configuration was synthesized for the first time. For this construction, TiO 2 NBs provide the 1D structure for a large superficial area and fast electron mobility, 0D CdS and CuS nanoparticles are the visible-light responsive nanomaterials, and Au nanoparticles serve as the surface plasmon resonance effect and electron transfer. The Au/CuS/CdS/TiO 2 NBs showed improved photocatalytic performance towards moxifloxacin (MOX) degradation, which can be attributed to the promoted photoabsorption contribution and enhanced separation and transfer of photoexcited electrons and holes. The morphology, constitution, optical and electrochemical properties of the prepared photocatalyst were investigated comprehensively. Moreover, the photocatalytic degradation mechanism and degradation by-products of moxifloxacin were studied. Results showed that the OH, O 2 − and h + are the main chemical oxidation species responsible for the degradation of MOX. Eight different photocatalytic degradation products were detected. The stability assessment showed that photodissolution plays the primary role in the photocatalytic performance decrease of Au/CuS/CdS/TiO 2 NBs. This work gives a promising strategy to rational design efficient hybrid metal-semiconductor photocatalysts for solar energy conversion.