This review article, authored by Agatino Di Paola, Elisa García-López, Giuseppe Marcì, and Leonardo Palmisano, focuses on the advancements in photocatalytic materials for environmental remediation. The authors highlight the extensive research conducted on TiO₂-based photocatalysts, which have been widely used in air cleaning and water purification. However, they also explore alternative photocatalysts that are not based on TiO₂, including modified and nanoassembled TiO₂, binary compounds, and ternary compounds. The review begins with an introduction to the field of heterogeneous photocatalysis, emphasizing its importance in various applications such as water splitting, hydrogen formation, and environmental remediation. It discusses the limitations of bare TiO₂, such as low light absorption in the visible region and high recombination rates of photogenerated electron-hole pairs, and the efforts to enhance these properties through modifications and nanostructuring. The article then delves into the preparation, characterization, and testing of binary, ternary, and quaternary compounds as potential alternatives to TiO₂. It covers various types of binary oxides, including ZnO, CuO, WO₃, V₂O₅, iron oxides, Bi₂O₃, and N-doped TiO₂. The binary sulfides are also discussed, along with their photocatalytic performance. For modified and nanoassembled TiO₂, the article examines the effects of adding activated carbon, carbon nanotubes (CNTs), and other conductive materials. These modifications enhance the photocatalytic activity by improving surface area, charge separation, and reactivity. The section on TiO₂/CNTs composites highlights the benefits of combining TiO₂ with CNTs, which facilitate charge transfer and reduce recombination. The review also explores the use of conjugated carbon materials, such as graphite, fullerene, and graphene, deposited on TiO₂. These materials improve the photocatalytic efficiency by enhancing charge separation and reducing recombination. The article discusses the synthesis methods and photocatalytic applications of these materials. Finally, the review discusses N-doped TiO₂, which has been developed to extend the absorption spectrum to the visible region, making it more efficient under solar light. The article reviews the synthesis methods, photocatalytic properties, and challenges associated with N-doped TiO₂. Overall, the review provides a comprehensive overview of the current state of photocatalytic materials for environmental remediation, highlighting both the advancements and limitations of different approaches.This review article, authored by Agatino Di Paola, Elisa García-López, Giuseppe Marcì, and Leonardo Palmisano, focuses on the advancements in photocatalytic materials for environmental remediation. The authors highlight the extensive research conducted on TiO₂-based photocatalysts, which have been widely used in air cleaning and water purification. However, they also explore alternative photocatalysts that are not based on TiO₂, including modified and nanoassembled TiO₂, binary compounds, and ternary compounds. The review begins with an introduction to the field of heterogeneous photocatalysis, emphasizing its importance in various applications such as water splitting, hydrogen formation, and environmental remediation. It discusses the limitations of bare TiO₂, such as low light absorption in the visible region and high recombination rates of photogenerated electron-hole pairs, and the efforts to enhance these properties through modifications and nanostructuring. The article then delves into the preparation, characterization, and testing of binary, ternary, and quaternary compounds as potential alternatives to TiO₂. It covers various types of binary oxides, including ZnO, CuO, WO₃, V₂O₅, iron oxides, Bi₂O₃, and N-doped TiO₂. The binary sulfides are also discussed, along with their photocatalytic performance. For modified and nanoassembled TiO₂, the article examines the effects of adding activated carbon, carbon nanotubes (CNTs), and other conductive materials. These modifications enhance the photocatalytic activity by improving surface area, charge separation, and reactivity. The section on TiO₂/CNTs composites highlights the benefits of combining TiO₂ with CNTs, which facilitate charge transfer and reduce recombination. The review also explores the use of conjugated carbon materials, such as graphite, fullerene, and graphene, deposited on TiO₂. These materials improve the photocatalytic efficiency by enhancing charge separation and reducing recombination. The article discusses the synthesis methods and photocatalytic applications of these materials. Finally, the review discusses N-doped TiO₂, which has been developed to extend the absorption spectrum to the visible region, making it more efficient under solar light. The article reviews the synthesis methods, photocatalytic properties, and challenges associated with N-doped TiO₂. Overall, the review provides a comprehensive overview of the current state of photocatalytic materials for environmental remediation, highlighting both the advancements and limitations of different approaches.