A review on conductive polymers-modified TiO2 photocatalyst for environmental remediation

Abstract

Titanium dioxide (TiO₂) has garnered significant research interest in recent years for its application in the photocatalytic degradation of organic matter, owing to its affordability, high chemical stability, and environmental compatibility. However, TiO₂’s wide band gap (3.0–3.2 eV) and low quantum efficiency (< 20 %) hinder its photocatalytic performance. Conductive polymers (CPs), due to their high electrical conductivity and adjustable band gaps, can enhance the absorption of visible light by TiO₂ and inhibit the recombination of electron-hole pairs, providing a solution to address these limitations. As a result, CPs are widely employed to modify TiO₂. This paper reviews the most commonly used CPs for TiO₂ modification, such as polyaniline (PANI), polypyrrole (PPy), and polythiophene (PTh), along with typical modification techniques. Studies the photocatalytic mechanism and the mechanism of enhanced photocatalytic activity of CPs-modified TiO₂, highlighting the roles of photosensitization and the synergistic effects of CPs modification in enhancing photocatalytic efficiency. Discusses the application of CPs-modified TiO₂ in water treatment, and finally looks ahead to the opportunities and challenges faced by the research on CPs-modified TiO₂.