Metal‐Free Nanoporous Carbons in Photocatalysis

Abstract

Evidences on the photochemical activity of semiconductor and metal-free nanoporous carbons upon irradiation in aqueous environments have opened new opportunities for these materials in photocatalysis, beyond their conventional use as inert supports of semiconductors. The aim of this chapter is to review the recent progress on the photocatalytic performance of nanoporous carbons under different illumination conditions, discussing the photochemical quantum yield of carbons of varied nature and physicochemical features towards the photodegradation of pollutants in water. The tight confinement inside the nanopores is important to minimize surface recombination and to increase the lifetime of the excitons photogenerated upon irradiation of the nanoporous carbons. Furthermore, matching of the molecular dimensions of the compound confined in the porosity of the carbon boosts the light conversion towards the visible spectrum. The composition of the nanoporous carbon is also essential for the stabilization of the charge carriers, and to promote additional transfer reactions involving chromophoric surface moieties decorating the carbon matrix that are capable of generating vacancies upon irradiation under sunlight. Some progress is yet to be done towards the understanding of the fundamentals of the light/carbon/molecule interactions to design photoactive nanoporous carbons with optimized features for an enhanced photocatalytic response under solar light.