Sustainable dual usage of spray-pyrolyzed Sb:SnO2 thin films for pollutant degradation and power generation

Abstract

Persistent energy shortages and increasing environmental pollution have accelerated the development and advancement of economically sustainable and environmentally benign solutions for power generation, pollutant remediation, and wastewater treatment. Traditional approaches for photocatalysis involve powder and particulate films, which possess several drawbacks, like poor stability, complex reusability, and the risk of secondary contamination. Thin-film-based photocatalysis has emerged as a viable technique for the effective degradation of organic contaminants in wastewater, taking advantage of the increased surface area, higher light absorption, and ease of recovery compared with typical powder and particulate coating photocatalysts. Herein, an Sb:SnO₂ thin film deposited via a facile spray pyrolysis method is presented as a low-material-loading photoelectrode with durability and stability in pollutant degradation (high photocatalytic rate per mass) under a cost-effective white LED light. Concurrently, the electrodes offer a sustainable approach for application in microbial fuel cells (MFCs) to remediate wastewater whilst generating bioelectricity. The Sb:SnO₂ thin-film electrodes limit the use of considerable amounts of graphite/iron loading in MFCs while offering maximum active surface area for microbial interactions. Thus, the electrodes demonstrate pollutant degradation, water remediation, and power generation, indicating their potential as multifunctional electrodes for a sustainable environment.