Nanophotocatalysis for Degradation of Organic Contaminants

NAPOLI, F.S.R.; URIARTE, D.; GARRIDO, M. ; DOMINI, C.; ACEBAL, C.

Handbook of Green and Sustainable Nanotechnology,

Springer

Lugar: Berlin; Año: 2022; p. 1 - 43

The continuous introduction of pollutants into the environment presents newchallenges for their total removal and promotes the development of novel strategies with high efficiencies. Photocatalysis can be defined as a photoinducedreaction which is accelerated by the presence of a catalyst. Semiconductornanomaterial-based photocatalysis is recognized as a promising alternative tothe conventional methods for pollutant removal owing to its low cost,non-toxicity, reusability, and high stability. Nano-materials used for photocatalysis show many advantages compared to bulk materials due to their unique properties, such as increased surface area and particular quantum effects. Nanophotocatalysts can be classified as metal oxide-based (TiO2, ZnO, Fe2O3) or metalfree-based (graphitic carbon nitride (g-C3N4), CdS, ZnS). Their wide or narrowband gap energies determine if the nanophotocatalysts require high or low energyUV light for their photocatalytic reactions. In this chapter, the most commonpollutants and the importance of their removal from the environment have beendiscussed. Moreover, the principles of photocatalysis along with different variables like the structure of the catalyst, the pH, the amount of the catalyst, and theintensity of the light that affect the photocatalysis of these pollutants have alsobeen mentioned comprehensively. The most commonly applied nanomaterials forthis purpose with their advantages and disadvantages are presented. Differentstrategies adopted for extending the photocatalytic active region to the visiblelight have also been offered including metal/non-metal doping, photosensitivematerials, combination with other nanoparticles, and composite formation.