Introduction

With the rapid progress of modern industry and agriculture, a large number of toxic and harmful pollutants have been released into the environment in recent years, which seriously threatens the survival and development of human beings and the ecological balance. Currently, degradation by photocatalytic reactions is considered to be the one of the primary methods for removing organic pollutants from environment. Because photocatalysis is a more thorough approach to environmental remediation, since it could completely mineralize organic pollutants into non-toxic inorganics CO₂ and H₂O under mild conditions without secondary pollution. The key to the utilization of photocatalytic technology is the development of photocatalytic materials, although a number of photocatalysts were used for degradation of organic pollutants, such as TiO₂, ZnO, CdS and g-C₃N₄, these photocatalysts often suffer from the rapid recombination of photogenerated electron-hole pairs, resulting in low photocatalytic efficiency and poor practical applications. Notably, as a type of new functional materials, MOFs and COFs with well-ordered porous structures and numerous active sites have been proven to be ideal photocatalysts for the degradation of organic pollutants^[1].

Degradation of Organic Pollutants by MOFs

MOFs can be used in the photocatalytic degradation of organic pollutants in both air and water. The details are as follow:

• Photocatalytic degradation of organic pollutants in air: MOFs and their derivatives have exhibited great performance for photocatalytic degradation of organic pollutants in air like formaldehyde, toluene, acetaldehyde, o-xylene, isopropanol, styrene. For example, Zhang et al. prepared NH₂-MIL-101(Fe) hexagonal microspindles for the photodegradation of gaseous toluene under irradiation of visible light, the degradation efficiency was up to 79.4%, which was much higher than that of the commercial photocatalysts^[2].
• Photocatalytic degradation of organic pollutants in water:  MOFs can be used for the photocatalytic degradation of various water pollutants such as (1) photocatalytic degradation of dyes like methylene blue, methylene orange and rhodamine B; (2) photocatalytic degradation of pharmaceuticals and personal care products like theophylline, ibuprofen, bispheno, tetracycline, amoxicillin and so on; (3) photocatalytic degradation of pesticides and herbicides like atrazine, methyl malathion, chlorpyrifos, methyl malathion and chlorpyrifos; (4) photocatalytic degradation of other organic pollutants like phenolic compounds and nitro-aromatics.

Degradation of Organic Pollutants by COFs

There are two ways for COFs used in photocatalytic degradation of organic pollutants. One is that the singlet oxygen was produced by photocatalyst and the  reactive oxygen ¹O₂ were used to kill pathogenic bacteria in the environment,  another is that photoexcited COFs catalyst is used to generate electrons and holes, which can reduce O₂ into ·O^2- and oxidize OH^- into ·OH^-, and then the ·O^2-  and ·OH^- are used to degrade pollutants. For the former method, the bacteria like grape mold and bacillus coli can be killed, for the latter one, the organic dye and heavy metal ion can be degraded.

What Can Alfa Chemistry Do

Alfa Chemistry provides various MOFs and COFs with high-activity for use in photocatalytic degradation of organic pollutants. And our professional technology team also provides customers with specialized, high-quality MOFs and COFs design and customization services, no matter what design ideas you have, we will implement them together with you. In addition, Alfa Chemistry is committed to supporting customers a series of solutions in photocatalytic degradation of organic pollutants by using MOFs and COFs. Please contact us immediately to order or cooperate in research and development with high quality and reasonable price.