Photoelectrochemical Degradation of Glyphosate Using Schottky Heterojunction between MXene and Graphitic Carbon Nitride Based Photocatalyst

Glyphosate is one of the most commonly used herbicides that is frequently observed in soil and water systems. Its persistence and toxicity pose serious concerns to human health and the environment. Conventional treatment methods such as adsorption and biological processes are often inadequate as these approaches either transfer the pollutant to another phase or show partial mineralization. In this work, MXene (Ti₃C₂Tx) and graphitic carbon nitride (g-C₃N₄) supported over activated carbon fibre (ACF) were integrated to create a Schottky-type heterojunction as a stable photoanode for photoelectrochemical (PEC) degradation of glyphosate. For single-chamber PEC operation, g-C₃N₄ served as the visible-light absorber, metallic MXene acted as an electron sink while ACF as a conductive and sustainable support. Strong interfacial coupling between MXene and g-C₃N₄ was established by structural and spectroscopic investigations that supported band bending at the interface and enabled effective charge separation. The hybrid system accelerated the oxidation of glyphosate by significantly increasing the production of reactive oxygen species. Under ideal conditions, glyphosate was degraded to around 100% in 270 min at a bias potential of 1.4 V. These findings highlight the potential of MXene-g-C₃N₄/ACF photoanode as a scalable, cost-effective, and visible light active platform for remediation of glyphosate and potentially other organic contaminants in water.