Review of TiO2-Graphitic Carbon Nitride Based Composites for the Degradation of Emerging Pollutants

Abstract

Photocatalysis using semiconductor materials has gained attention for its potential in tackling environmental and energy-related challenges. Titanium dioxide (TiO₂) is widely used for its stability, low cost, and non-toxicity, though its photocatalytic activity is limited to the UV region due to its wide band gap and rapid electron-hole recombination. Concurrently, graphitic carbon nitride (g-C₃N₄), a visible-light-responsive, metal-free polymeric semiconductor, has emerged as a promising partner to form heterojunctions with TiO₂. The formation of these heterojunctions enhances charge separation, broadens visible-light absorption, and improves photocatalytic performance. This review explores and compares synthesis methods for TiO₂–g-C₃N₄ composites and their potential to degrade emerging pollutants.