Sustainable hybrid photocatalysts: titania immobilized on carbon materials derived from renewable and biodegradable resources

This review comprises the preparation, properties and heterogeneous photocatalytic applications of TiO₂ immobilized on carbon materials derived from earth-abundant, renewable and biodegradable agricultural residues and sea food waste resources. The overview provides key scientific insights into widely used TiO₂ supported on carbonaceous materials emanating from biopolymeric materials such as lignin, cellulose, cellulose acetate, bacterial cellulose, bamboo, wood, starch, chitosan and agricultural residues (biochar, charcoal, activated carbon and their magnetic forms, coal fly ash) or seafood wastes namely eggshell, clamshell and fish scales; materials that serve as a support/template for TiO₂. Heightened awareness and future inspirational developments for the valorisation of various forms of carbonaceous functional materials is the main objective. This appraisal abridges various strategies available to upgrade renewable carbon-based feedstock <i>via</i> the generation of sustainable TiO₂/carbon functional materials and provides remarks on their future prospects. Hopefully, this will stimulate the development of efficient and novel composite photocatalysts and engender the necessary knowledge base for further advancements in greener photocatalytic technologies.