ABSTRACT
Rapid urbanization and transportation during the last few decades have given rise to a number of environmental problems such as wastewater supply, wastewater generation, and its collection, treatment, and disposal. Water scarcity is becoming a burning problem as water resources are being polluted at an ever-increasing pace. This problem will be more severe in the next few decades. The majority of industries do not give priority to the treatment of their efuents or to recycling the water. Photocatalytic technology utilizing abundant solar light holds great promise to tackle such challenging environmental and energy issues. In recent years, various types of photocatalysts that are active for environmental purication have been developed.
