The disposal of dye-contaminated wastewater is a major concern around the world for which a variety of techniques are used for its treatment. The photocatalytic treatment of dye-contaminated wastewater is one of the treatment methods. Semiconductor-assisted photocatalytic treatment of dye-contaminated wastewater has gained pronounced attention recently. This review outlines the recent advancements in the photocatalytic treatment of dye-contaminated wastewater. The photocatalytic degradation of dyes follows three types of mechanisms: (1) dye sensitization through charge injection, (2) indirect dye degradation through oxidation/reduction, and (3) direct photolysis of dye. Several experimental parameters like initial concentration of dyes, pH, and catalyst dosage significantly affect the photocatalytic degradation of dyes. The photocatalytic materials can be categorized into three generations. The single-component (e.g., ZnO, TiO₂) and multiple component semiconductor metal oxides (e.g., ZnO–TiO₂, Bi₂O₃–ZnO) are categorized as first-generation and second-generation photocatalysts, respectively. The photocatalysts dispersed on an inert solid substrate (e.g., Ag–Al₂O₃, ZnO–C) are classified as third-generation photocatalysts. Finally, we reviewed the challenges that affect the photocatalytic degradation of dyes.

染料污染废水的处理是世界范围内的一个主要问题，为此使用了多种技术进行处理。染料污染废水的光催化处理是处理方法之一。半导体辅助光催化处理染料污染废水最近受到了广泛关注。本综述概述了染料污染废水的光催化处理的最新进展。染料的光催化降解遵循三种类型的机制：(1) 通过电荷注入的染料敏化，(2) 通过氧化/还原的间接染料降解，以及 (3) 染料的直接光解。染料的初始浓度、pH 值和催化剂用量等几个实验参数显着影响染料的光催化降解。光催化材料可分为三代。单组分（例如 ZnO、TiO₂ )和多组分半导体金属氧化物(如ZnO–TiO ₂ , Bi ₂ O ₃ –ZnO)分别被归类为第一代和第二代光催化剂。分散在惰性固体基质（如Ag-Al2O3、ZnO-C）上的光催化剂_被归类_为第三代光催化剂。最后，我们回顾了影响染料光催化降解的挑战。