Photocatalytic Degradation Of Dyes

Introduction

Water pollution is an escalating global issue, with industrial effluents being one of the major contributors. Many synthetic dyes are known to be toxic, carcinogenic, and mutagenic. When released into aquatic ecosystems without adequate treatment, they can significantly reduce light penetration, disrupt photosynthetic activity in aquatic plants, and pose serious health risks to aquatic organisms and humans alike. Therefore, the removal of dyes from wastewater before discharge into the environment is a critical step in sustainable water management.

In recent years, photocatalytic degradation has emerged as a highly promising technique for dye removal. This advanced oxidation process (AOP) harnesses light energy—typically from UV or visible light sources—to activate a semiconductor catalyst. The activated catalyst generates reactive oxygen species (ROS) such as hydroxyl radicals, which are powerful oxidants capable of decomposing dye molecules into harmless end products like carbon dioxide and water.

This book chapter aims to provide a comprehensive overview of the principles, materials, mechanisms, and applications of photocatalytic degradation for dye removal.