Ternary synergy: a TiO₂/BiVO₄/AC composite for sustainable water purification

A ternary TiO₂/BiVO₄/activated carbon (AC) heterostructure was synthesized and evaluated for photocatalytic degradation of phenol and methylene blue (MB) under UVA and visible light. Structural and optical analyses confirmed an S-scheme TiO₂–BiVO₄ junction uniformly distributed on porous AC, with reduced band gap (2.41 eV). AC incorporation enhanced adsorption, light absorption, and charge separation. The composite achieved up to 99% phenol removal and 96% MB degradation under UVA, retained ~ 81% efficiency after five cycles, and showed broad-spectrum activity. Radical scavenging indicated valence band holes and superoxide radicals as dominant species. The synergistic charge separation, adsorption, and extended photoresponse make TiO₂/BiVO₄/AC a promising photocatalyst for water purification.