Heterogeneous Photocatalysis Scalability for Environmental Remediation: Opportunities and Challenges

Abstract

Heterogeneous photocatalysis is an ecofriendly technique for purifying organic pollutants in environmental systems. While pilot-scale photoreactors have explored photocatalytic system upscalibility, their practical implementation is restricted for various reasons. These include feed composition alteration, complicated photoreactor designs, high operation and synthesis costs, photocatalyst poisoning, low quantum yield under solar irradiation, fast exciton recombination, and low reuse or regeneration capabilities. In this paper, we highlight the photocatalyst scalability challenges for real-world applications. We also provide an in-depth discussion on photocatalyst opportunities for effective air and water pollution control. Lastly, we offer a contemporary perspective on photocatalysis scale-up for the real environmental treatment.

Síntesis verde de materiales nanoestructurados de ZnO en la degradación de contaminantes orgánicos por medio de la fotocatálisis heterogénea

“…Entonces cuando tenemos un colorante y se le agrega un semiconductor, y lo iluminamos con luz UV esta tiene mayor energía (Luz UV = 3.94 eV) que la energía de banda prohibida, entonces un electrón (e -) se mueve desde la VB hacia la CB creando un hueco en la VB. Los pares electro-huecos creados se separan y generan portadores de carga eléctrica que migran a la superficie del sólido donde reaccionan con H2O y O2 adsorbidos, dando como resultado la formación de especies activas como los radicales hidroxilos (OH*), el peróxido de hidrógeno (H2O2) y los súper óxidos (O2 − ) que catalizan en la superficie de la partícula semiconductora [20]- [22].…”

Ti2O3/TiO2-Assisted Solar Photocatalytic Degradation of 4-tert-Butylphenol in Water

“…Heterogeneous photocatalysis may be considered an economically feasible solution to remove 4-t-BP from water due to the competitive cost of the process and the ambient conditions of temperature and pressure [25][26][27]. Moreover, it is considered an environmentally friendly oxidation process since it allows not only the degradation of the pollutant from the contaminated system but also its total elimination, without generating any undesired by-products, which could be even more toxic compounds than the parent one [28,29].…”

The enhanced visible-light-induced photocatalytic activities of bimetallic Mn–Fe MOFs for the highly efficient reductive removal of Cr(vi)

“…8 Due to the instantaneous charge separation, the moderate tunability, and chemical instability, the application of prevalent semiconductors as photocatalysts is restricted, and researches are concentrated on nding novel, tunable and efficient photocatalysts. 9 Compared with conventional inorganic semiconductors, metal-organic frameworks (MOFs), a category of porous materials built from metal ions and organic linkers, have been lately considered as photocatalysts owing to their striking advantages in the following features: (1) the high porosity of MOFs permits the availability of catalytic sites and accelerates the transport of reactants; (2) the tunability of MOFs creates an excellent opportunity to develop the light response over the visible range;…”