The article reviews the research progress on the modification of titanium dioxide (TiO₂) photocatalysts and their application in the photodegradation of organic pollutants. TiO₂, known for its excellent photocatalytic activity, high photoelectric conversion efficiency, and economic viability, has been widely used for azo dye degradation. However, its inherent limitations, such as limited visible light absorption and rapid charge carrier recombination, have hindered broader applications. To address these issues, various modification techniques have been explored, including precious metal deposition, transition metal doping, rare earth metal doping, composite semiconductors, and composite polymers. These modifications enhance TiO₂'s absorption capacity in the visible region and reduce carrier recombination rates, significantly improving its photocatalytic performance. The article discusses the synthesis methods of TiO₂, such as sol-gel, hydrothermal, atomic layer deposition, and microemulsion, and their advantages and disadvantages. It also delves into the mechanisms and kinetics of photodegradation, emphasizing the importance of understanding these processes to optimize degradation efficiency. The review highlights the significant advancements in TiO₂ modification, including the improvement of specific surface area, reduction of band gap energy, and enhancement of charge carrier separation. These modifications have broadened the photoresponse range and improved the utilization of sunlight, making TiO₂ photocatalysts more efficient and versatile. Despite the progress, challenges remain, such as stability issues and high preparation costs. Future research directions include optimizing modification methods, enhancing stability, reducing costs, and improving performance in various real-world environments. The article concludes by emphasizing the potential of TiO₂ photocatalysts in environmental governance and sustainable development, with a focus on developing more efficient, stable, and environmentally friendly materials.The article reviews the research progress on the modification of titanium dioxide (TiO₂) photocatalysts and their application in the photodegradation of organic pollutants. TiO₂, known for its excellent photocatalytic activity, high photoelectric conversion efficiency, and economic viability, has been widely used for azo dye degradation. However, its inherent limitations, such as limited visible light absorption and rapid charge carrier recombination, have hindered broader applications. To address these issues, various modification techniques have been explored, including precious metal deposition, transition metal doping, rare earth metal doping, composite semiconductors, and composite polymers. These modifications enhance TiO₂'s absorption capacity in the visible region and reduce carrier recombination rates, significantly improving its photocatalytic performance. The article discusses the synthesis methods of TiO₂, such as sol-gel, hydrothermal, atomic layer deposition, and microemulsion, and their advantages and disadvantages. It also delves into the mechanisms and kinetics of photodegradation, emphasizing the importance of understanding these processes to optimize degradation efficiency. The review highlights the significant advancements in TiO₂ modification, including the improvement of specific surface area, reduction of band gap energy, and enhancement of charge carrier separation. These modifications have broadened the photoresponse range and improved the utilization of sunlight, making TiO₂ photocatalysts more efficient and versatile. Despite the progress, challenges remain, such as stability issues and high preparation costs. Future research directions include optimizing modification methods, enhancing stability, reducing costs, and improving performance in various real-world environments. The article concludes by emphasizing the potential of TiO₂ photocatalysts in environmental governance and sustainable development, with a focus on developing more efficient, stable, and environmentally friendly materials.