Synergistic photocatalytic nanozymes to promote contaminant removal and hydrogen production

Photocatalytic nanozymes, which combine light-induced redox reactions and enzyme-like catalysis, have emerged as a promising class of nanomaterials. This alliance offers tremendous potential for light- enhanced enzyme-like activity and expands the applications of nanozymes in energy and environmental fields. In this study, a photocatalytic nanozyme OVs-TiO2/Pd hybrid nanosheets (HNSs) with abundant oxygen vacancies (OVs) and controllable Pd component was prepared by a one-step solid-phase reduction method. Benefiting from the synergistic effect and the strong metal-support interaction, OVs-TiO2/Pd HNSs exhibit remarkable light-enhanced oxidase-like and hydrogenase-like activity, they efficiently catalyze the degradation of antibiotics and the production of hydrogen, respectively. Electron spin resonance and transient photovoltage techniques elucidated that the enhanced enzyme-like activities are attributed to the increased generation of charge carriers and reactive oxygen species. This study builds a bridge between photocatalysis and enzyme-like catalysis, opening up a new avenue to explore the multiple functional nanomaterials for a myriad of applications.