Work

Interfacial engineering of sulfur-modified g-C3N5/V2O5 heterostructures for enhanced overall water splitting and sonophotocatalytic tetracycline degradation

Year: 2026

Type: article

Abstract: Electrochemical water splitting (EWS) and photocatalytic advanced oxidation processes (AOPs) are promising approaches for clean hydrogen production and environmental remediation; however, their efficiency is often limited by high overpotentials, rapid charge recombination, and poor catalyst stability. To address these issues, multifunctional catalysts were synthesized by coupling V 2 O 5 with g-C 3 N 5 (CN) and sulfur-modified g-C 3 N 5 (SCN), forming V 2 O 5 @x%SCN composites (x = 10, 20, and 30 wt%; denoted as VSCN-1, VSCN-2, and VSCN-3). Among them, the optimized VSCN-2 supported on nickel foam exhibited the highest electrocatalytic activity in 1 M KOH, requiring low overpotentials (η) of 250 mV for the oxygen evolution reaction (OER) and 89 mV for the hydrogen evolution reaction (HER) at 10 mA/cm 2 . It also exhibited low Tafel slopes of 68/109 mV/dec (OER/HER) with stable operation over 60 h. The VSCN-2‖VSCN-2 electrolyzer achieved a low cell voltage of 1.55 V at 10 mA/cm 2 and maintained stable performance for 80 h. In photocatalytic applications, VSCN-2 achieved 99% tetracycline (TC) removal under light-emitting diode (LED) irradiation during sonophotocatalysis (SPC) and retained its activity over repeated cycles. Radical-scavenging experiments and ESR analysis indicated that • O 2 − and • OH were the dominant reactive species involved in TC degradation, supporting the proposed charge transfer mechanism. LC–MS and ECOSAR analyses provided further evidence for the degradation pathways and the formation of products with lower predicted toxicity. The improved performance is attributed to enhanced interfacial charge transfer in the V 2 O 5 /SCN heterostructure, highlighting its potential as a multifunctional catalyst for water splitting and environmental remediation.

Source: Advanced Composites and Hybrid Materials

DOI: 10.1007/s42114-026-02085-y