Insight into MoS₂ Synthesis with Biophotoelectrochemical Engineering and Applications in Levofloxacin Elimination

Biosynthesis of nanomaterials is an emerging technology in recent decades ascribed to its unique “greener” route and higher energy efficiency. It is superior to the traditional physicochemical synthesis processes, in which hazardous intermediates or high energy-consumption are often inevitable and remain a significant obstacle. In this work, a coupling system based on a photodriven microbial fuel cell (MFC) was constructed to controllably synthesize different sizes of MoS2 nanomaterials in situ. By virtue of the MFC producing electricity as a driving force, the MoS42– ions could be reduced to MoS2 nanoparticles. Impressively, photoexcited electrons produced from a polydopamine coated TiO2 nanotube (PDA/TiO2 NT) electrode under visible light irradiation (>420 nm) could also be utilized online to facilitate MoS2 nanoparticle growth effectively. Interestingly, the MoS2 material was further cultivated on a PDA/TiO2 substrate and then biologically modified MoS2/PDA/TiO2 electrodes were easily obtained, which exhibited unique hydrophilic behavior (14.74°) and bioelectrocatalytic performance for effectively promoting the complete removal of antibiotics in the MFC and photoelectrocatalytic (PEC) cooperative system. Thus, we believe that such obvious advantages of the constructed photoboosted MFC system could provide an environmentally benign pathway to synthesize nanostructured electrode materials and create new opportunities for diverse pollutant removal in situ.