ZnO/Cu2O heterojunctions treated glass surface for photocatalytic and self-cleaning applications

Abstract

Here we report the synthesis route for glass surface functionalization by ZnO nanorods and nanowires-based Cu2O heterojunction. In the first step, ZnO elongated structures were grown on a seeded substrate following the classic hydrothermal method, and their thickness can be controlled by polyethyleneimine (PEI) concentration. In the second step, ZnO/Cu2O heterojunctions were fabricated by immersion of ZnO-grown substrate upside-down into the copper sulfate solution with glucose as a reducing agent. After characterization of prepared ZnO/Cu2O heterojunction by SEM, TEM, and XRD, its application capability for waste-water treatment was successfully demonstrated on Estriol (E3) hormone degradation under UV light by using a continuous Drip Flow Biofilm Reactor. Furthermore, functionalized glasses were shown to be effective for designing self-cleaning surfaces. The photocatalytic-induced self-cleaning ability was demonstrated by resazurin-based smart ink and tert-butyl alcohol-based methylene blue ink.