Hybridized 2D Nanomaterials Toward Highly Efficient Photocatalysis for Degrading Pollutants: Current Status and Future Perspectives

Abstract

Organic pollutants including industrial dyes and chemicals and agricultural waste have become a major environmental issue in recent years. As an alternative to simple adsorption, photocatalytic decontamination is an efficient and energy‐saving technology to eliminate these pollutants from water environment, utilizing the energy of external light, and unique function of photocatalysts. Having a large specific surface area, numerous active sites, and varied band structures, 2D nanosheets have exhibited promising applications as an efficient photocatalyst for degrading organic pollutants, particularly hybridization with other functional components. The novel hybridization of 2D nanomaterials with various functional species is summarized systematically with emphasis on their enhanced photocatalytic activities and outstanding performances in environmental remediation. First, the mechanism of photocatalytic degradation is given for discussing the advantages/shortcomings of regular 2D materials and identifying the importance of constructing hybrid 2D photocatalysts. An overview of several types of intensively investigated 2D nanomaterials (i.e., graphene, g‐C3N4, MoS2, WO3, Bi2O3, and BiOX) is then given to indicate their hybridized methodologies, synergistic effect, and improved applications in decontamination of organic dyes and other pollutants. Finally, future research directions are rationally suggested based on the current challenges.

Multi‐Component Mesocrystalline Nanoparticles with Enhanced Photocatalytic Activity

“…[ 49 ] The highly reactive OH radicals produced in the above processes effectively decompose methylene blue dye, a model organic pollutant molecule, into unit molecules such as CO 2 and H 2 O. [ 50–52 ]…”

“…[49] The highly reactive OH radicals produced in the above processes effectively decompose methylene blue dye, a model organic pollutant molecule, into unit molecules such as CO 2 and H 2 O. [50][51][52] The photocatalytic performances of mesocrystalline nanoparticles were measured by the degradation of methylene blue (MB) solution under visible light in the presence of H 2 O 2 . Detailed conditions of photo-Fenton-like catalytic processes such as the amount of H 2 O 2 , dye concentration, and pH were set according to previous studies ( Figure S13, Supporting Information).…”

MoS2-based nanocomposites for cancer diagnosis and therapy

“…Two-dimensional nanomaterials (MoS 2 , MoSe 2 , WS 2 , WSe 2 , and etc.) have attracted great interest in the biomedical field [ 8 , 18 , [386] , [387] , [388] , [389] , [390] , [391] , [392] , [393] , [394] , [395] , [396] , [397] ], especially MoS 2 -based nanocomposites due to their outstanding physi-chemical properties and good biocompatibility. MoS 2 with a large specific surface area can load various biomolecules, drugs, fluorescent molecules, and other nanomaterials to improve its colloidal stability and tumor targeting, increase its sensitivity and accuracy in detecting specific biomarkers, and enhance its specific response to the stimulation of tumor microenvironment, which reduces side effects during treatment.…”

Recent Progress on Fullerene-Based Materials: Synthesis, Properties, Modifications, and Photocatalytic Applications

“…Generally, for photocatalytic decontamination, the separated holes and electrons of the semiconductor can react with ambient substances (i.e., H 2 O and O 2 ) to produce free radicals (i.e., •OH, •O 2 − , HO 2 •, H 2 O 2 ). Then, the highly oxidative holes and reactive radicals will intensively degrade organic pollutants into small molecules or inorganic materials through addition/substitution reaction and electron transfer between contaminants and free radicals [ 29 ]. Through the processes above, the pollution is mitigated or eliminated.…”