Single-step electrodeposited ZnO/MXene hybrid photoelectrodes for visible-light-driven photoelectrocatalytic treatment of industrial wastewater

The development of scalable and efficient photoelectrodes for the treatment of chromophore-contaminated industrial wastewater remains challenging due to limitations in charge separation and performance in complex effluents. Herein, ZnO/Ti₃C₂Tₓ MXene (ZnO–MX) hybrid photoelectrodes were fabricated on indium tin oxide (ITO) substrates via a single-step aqueous electrodeposition technique and evaluated in electrodeposition-assisted photoelectrocatalysis (ED–PEC) under visible-light irradiation. An optimal MXene loading of 1.0 wt% significantly enhanced interfacial charge transport, reducing charge-transfer resistance by ~ 60% and increasing photocurrent density by ~ 35% relative to ZnO. The optimized electrode achieved removal efficiencies of 99.2% for methylene blue and 92.1% for Congo red at low concentrations in model solutions and maintained 92.6% and 85.8% removal, respectively, in industrial textile wastewater containing multiple chromophores and high organic load. The system also removed ~ 70% or more of additional constituents and retained ~ 80% of its activity after six reuse cycles. Furthermore, an interpretable multi-output neural network was developed to quantify the effects of initial concentration and irradiation time on removal performance. This work enables a practical, scalable hybrid electrode platform for advanced industrial wastewater treatment.