Note: Intro -- Contents -- 1 Dyes and Pigments: Interventions and How Safe and Sustainable Are Colors of Life!!! -- 1.1 Introduction -- 1.1.1 Ancient History of Uses of Dyes -- 1.2 Classification of Dyes -- 1.2.1 Natural Dyes -- 1.2.2 Synthetic Dye -- 1.2.3 Pigments -- 1.3 Application of Dyes -- 1.3.1 In Textile Sector -- 1.3.2 In Food Industry or Food Supply Chain -- 1.3.3 In Packaging and allied Sectors -- 1.3.4 In Cosmetic Sector -- 1.4 Toxic Implications Production and Discharge to Effluents -- 1.5 Guidelines -- 1.5.1 Market Scenario and Growth of Dyes and Pigments -- 1.5.2 New Designing of Dyes Using Computed Programming for Functional Applications -- 1.5.3 Bacterial Pigments with Reduced or Minimal Toxicity Implications -- 1.6 Future Prospects -- 1.7 Conclusion -- References -- 2 Recent Advances in Photocatalytic Degradation of Dyes Using Heterogeneous Catalysts -- 2.1 Introduction -- 2.2 Classification of Dyes -- 2.3 Impact of Textile Dyes on the Environment -- 2.4 Principle of Photocatalysis and Mechanistic Pathways -- 2.4.1 Photocatalysts -- 2.4.2 Basic Principle of Photocatalysis -- 2.5 Effect of Key Operational Parameters -- 2.5.1 Effect of pH -- 2.5.2 Effect of the Dose of Semiconductor -- 2.5.3 Effect of the Initial Concentration of Dye -- 2.5.4 Effect of Additives -- 2.5.5 Effect of Temperature -- 2.5.6 Effect of Light Intensity and Wavelength -- 2.5.7 Effect of Irradiation Time -- 2.6 Degradation Studies of Dyes -- 2.6.1 General Considerations -- 2.6.2 Photocatalytic Degradation Scheme for an Azo Dye -- 2.6.3 Effect of Substituents -- 2.6.4 Comparison of Cationic and Anionic Dye -- 2.6.5 Correlation of Dye Degradation with Its Type -- 2.6.6 Effect of Doping and Mixed Semiconductors -- 2.7 Types of Heterogeneous Photocatalysts -- 2.7.1 TiO2 Catalyst -- 2.7.2 ZnO Catalyst -- 2.7.3 Other Photocatalysts. , 2.8 Application of Heterogeneous Photocatalysis -- 2.8.1 Self-Cleaning -- 2.8.2 Air Cleaning -- 2.8.3 Application for Water and Wastewater Treatment -- 2.8.4 Removal of Trace Metals -- 2.8.5 Removal of Inorganic Compounds -- 2.8.6 Applications in Photodynamic Therapy -- 2.9 Conclusion and Outlook -- References -- 3 Recent Developments in Photocatalytic Techniques of Dye Degradation in Effluents -- 3.1 Introduction -- 3.2 Literature -- 3.3 Photocatalytic Dye Degradation Chemical Phenomena in Core-Shell -- 3.4 Optimization of Variables in Photocatalysis of Dye Degradation -- 3.4.1 pH Variable Effect on the Dye's Degradation Chemical Phenomena -- 3.4.2 Issues Still to Be Handled with New Trends -- 3.5 Summary -- References -- 4 Role of Doped Semiconductors in the Catalytic Activity -- 4.1 Introduction -- 4.2 Photocatalytic Mechanism and Influencing Factor -- 4.2.1 Reaction Mechanism -- 4.3 Metal-Doped Semiconductor -- 4.3.1 Silver and Gold Doped Semiconductor -- 4.3.2 Silver Doped Semiconductor -- 4.3.3 Palladium Doped Semiconductor -- 4.3.4 Ag-Doped TiO2 -- 4.3.5 Au-TiO2 -- 4.4 Conclusion -- References -- 5 Hybrid Treatment Technologies for Dye Degradation in Wastewater -- 5.1 Introduction -- 5.2 Advanced Treatment Technologies -- 5.2.1 Fenton-Type Processes -- 5.2.2 Irradiation Based Processes -- 5.2.3 Ozone Based Processes -- 5.2.4 Other AOPs -- 5.3 Limitations of AOPs -- 5.4 Emerging Hybrid Treatment Technologies -- 5.4.1 Photochemical Processes Coupled with Electrochemical Processes -- 5.4.2 Photochemical Processes Coupled with Sonolytic Processes -- 5.5 Conclusions and Future Prospects -- References -- 6 Aerogel Nanomaterials for Dye Degradation -- 6.1 Introduction -- 6.1.1 Aerogel-Overview -- 6.2 Classification, Properties and Applications -- 6.2.1 Synthesis of Aerogel Materials -- 6.2.2 Dye Degradation using Aerogel Materials -- 6.3 Conclusion. , References -- 7 Effective Materials in the Photocatalytic Treatment of Dyestuffs and Stained Wastewater -- 7.1 Introduction -- 7.2 Classification of Dyes -- 7.3 Photocatalysis -- 7.3.1 The Process of Photocatalysis -- 7.3.2 Direct Mechanism for Dye Degradation -- 7.3.3 The Mechanism of Indirect Degradation of Dye -- 7.4 Factors Affecting Photocatalytic Performances -- 7.4.1 pH -- 7.4.2 Light Intensity -- 7.4.3 Feed Flow Rate -- 7.5 Concentration of Reactants -- 7.5.1 Number of Catalysts Loading Layers on Substrate -- 7.6 Temperature During Catalyst Immobilisation -- 7.6.1 Ions Species -- 7.7 Photocatalysis of Wastewater -- 7.8 Dye Removal From Wastewater May Be Accomplished Using a Variety of Methods -- 7.8.1 Adsorption Technique -- 7.8.2 Advanced Oxidation Process (AOP) -- 7.8.3 Bioremediation and Biodegradation -- 7.8.4 Electrochemical Method -- 7.8.5 Ion-Exchange Method -- 7.8.6 Membrane Filtration Technique -- 7.9 Modulation of Photocatalysis of Wastewater by Dyes -- 7.9.1 Methyl Orange -- 7.9.2 Indigo Carmine -- 7.9.3 Malachite Green -- 7.9.4 Rhodamine B -- 7.9.5 Methylene Blue -- 7.10 Conclusion -- References -- 8 Optimizing Nanocatalyst's and Technological Factors Influencing on Photocatalytic Degradation of Organic and Inorganic Pollutants -- 8.1 Introduction -- 8.2 Significance of Photocatalysis in Water Treatment -- 8.3 Mechanism of Nanoparticles (Photocatalyst) Involved in Photocatalysis of Wastewater Pollutants -- 8.4 Factors Influencing on the Photocatalysis Mechanism -- 8.5 Conclusion -- References -- 9 Biological Synthesis of Metallic Nanoparticles and Their Application in Photocatalysis -- 9.1 Introduction -- 9.2 Preparation of Metallic Nanoparticles -- 9.2.1 Physical Methods -- 9.2.2 Chemical Methods -- 9.2.3 Biological Methods -- 9.3 Biological Synthesis -- 9.3.1 Plant Components in Metallic Nanoparticles Synthesis. , 9.3.2 Microbial Components in Metal Oxide Nanoparticle Synthesis -- 9.3.3 Animal Components in Metal Oxide Nanoparticle Synthesis -- 9.4 Mechanism of Biological Synthesis of Metallic Nanoparticles Using Plant Extract -- 9.5 Advantages and Disadvantages of Biological Synthesis of Metallic Nanoparticles -- 9.6 Photocatalysis -- 9.6.1 Mechanism of Photocatalysis -- 9.6.2 Factors Affecting Photocatalysis Process -- 9.6.3 Role of Photocatalytic Process Against Different Wastewater Pollutants -- 9.7 Photocatalysts -- 9.7.1 Selection of Nanomaterials as Photocatalysts -- 9.7.2 Metal Oxide Nanoparticles Photocatalysts -- 9.7.3 Nanocomposites and Other Photocatalysts -- 9.8 Future Scope and Conclusion -- References -- 10 Mechanistic Aspect of the Dye Degradation Using Photocatalysts -- 10.1 Introduction -- 10.2 Classification of Dyes -- 10.3 Dye-Related Toxicity -- 10.4 Techniques for Investigating Dye Degradation -- 10.5 Strategies for Dealing with Dye -- 10.5.1 Physical Mechanistic Procedures -- 10.5.2 Chemical Approaches -- 10.5.3 Biological Remediation -- 10.6 The Fundamentals of Photocatalysis -- 10.6.1 Photocatalytic Routes and Their Mechanism -- 10.6.2 Photocatalyst -- 10.6.3 Parameters Affecting Photocatalytic Degradation -- 10.6.4 Intermediary Product Detection -- 10.7 Conclusion -- References.