Bio-inspired Spinach-leaf-based Au/ZnO Nanocomposites as Photocatalyst

A photocatalyst of Au/ZnO (s-Au/ZnO) has been prepared via an approach, which uses spinach leaves with interconnected hierarchical structure as sacrificial biological template. The resultant s-Au/ZnO has well maintained the physical characteristics of the spinach leaf and demonstrated superior photocatalytic performance as well as enhanced photocurrent generation capability. Moreover, functional sacrificial agents (AgNO3, ammonium oxalate (AO) and tert-butyl alcohol (TBA)) have been employed to quench electrons, holes and hydroxyl radicals respectively to identify the active species of photocatalytic reaction and to investigate the mechanism of photocatalytic degradation. The facile method herein presented provides a convenient option for the preparation of bio-inspired leaf-like photocatalysts of ZnO-based nano-materials, holding potential applications in not only environmental purification but also solar-to-electric energy conversion.