Ecotechnological strategies in the development of alternative photocatalysts

Heterogeneous photocatalysis is presented here as a versatile, low-cost and environmentally treatment technology for a broad scope of pollutants. The efficient and successful application of photocatalysis demands that the pollutant, the catalyst and the source of illumination being in close proximity or contact with each other. The ability of advanced oxidation technology to remove low levels of persistent organic pollutants in water has been widely demonstrated and, progressively, the technology has been now being commercialized in many areas. This review discusses recent developments of alternative photocatalysts in the research and application of heterogeneous photocatalysis for the treatment of organic pollutants. The preparation of photocatalysts from industrial and agroindustrial residues, acting as precursor for support or for catalytic species will be discussed.