TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the...TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the reaction mechanism of Z‐scheme photocatalysts,recent research progress in the application of TiO2‐based Z‐scheme photocatalysts,and improved methods for photocatalytic performance enhancement are explored.Their applications,including water splitting,CO2reduction,decomposition of volatile organic compounds,and degradation of organic pollutants,are also described.The main factors affecting the photocatalytic performance of TiO2‐based Z‐scheme photocatalysts,such as pH,conductive medium,cocatalyst,architecture,and mass ratio,are discussed.Concluding remarks are presented,and some suggestions for the future development of TiO2‐based Z‐scheme photocatalysts are highlighted.展开更多
As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemic...As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemical, graphitic carbon nitride (g-C3N4) has become research hotspots in the community. However, g-C3N4 photocatalyst still suffers from many problems, resulting in unsatisfactory photocatalytic activity such as low specific surface area, high charge recombination and insufficient visible light utilization. Since 2009, g-C3N4-based heterostructures have attracted the attention of scientists worldwide for their greatly enhanced photocatalytic performance. Overall, this review summarizes the recent advances of g-C3N4-based nanocomposites modified with transition metal sulfide (TMS), including (1) preparation of pristine g-C3N4,(2) modification strategies of g-C3N4,(3) design principles of TMS-modified g-C3N4 heterostructured photocatalysts, and (4) applications in energy conversion. What is more, the characteristics and transfer mechanisms of each classification of the metal sulfide heterojunction system will be critically reviewed, spanning from the following categories:(1) Type I heterojunction,(2) Type II heterojunction,(3) p-n heterojunction,(4) Schottky junction and (5) Z-scheme heterojunction. Apart from that, the application of g-C3N4-based heterostructured photocatalysts in H2 evolution, CO2 reduction, N2 fixation and pollutant degradation will also be systematically presented. Last but not least, this review will conclude with invigorating perspectives, limitations and prospects for further advancing g-C3N4-based heterostructured photocatalysts toward practical benefits for a sustainable future.展开更多
The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxid...The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxidation processes（AOP）have been focused for removal of dye from waste water due to their advantages such as ecofriendly,economic and capable to degrade many dyes or organic pollutant present in water.Photocatalysis is one of the advance oxidation processes,mainly carried out under irradiation of light and suitable photocatalytic materials.The photocatalytic activity of the photocatalytic materials mainly depends on the band gap,surface area,and generation of electron–hole pair for degradation dyes present in water.It has been observed that the surface area plays a major role in photocatalytic degradation of dyes,by providing higher surface area,which leads to the higher adsorption of dye molecule on the surface of photocatalyst and enhances the photocatalytic activity.This present review discusses the synergic effect of adsorption of dyes on the photocatalytic efficiency of various nanostructured high surface area photocatalysts.In addition,it also provides the properties of the water polluting dyes,their mechanism and various photocatalytic materials;and their morphology used for the dye degradation under irradiation of light along with the future prospects of highly adsorptive photocatalytic material and their application in photocatalytic removal of dye from waste water.展开更多
As a class of famous carbon materials,biochars(BCs)and their derivative materials with excellent physicochemical properties and diversified functionalities present great potential in wastewater treatment fields.This r...As a class of famous carbon materials,biochars(BCs)and their derivative materials with excellent physicochemical properties and diversified functionalities present great potential in wastewater treatment fields.This review focuses on the latest development in reported biochar-based materials as superior adsorbents or catalysts for removing harmful organic contaminants from wastewater.The construction and properties of biochar-based materials are briefly introduced at the beginning.As one of the major factors affecting the properties of BCs,the wide diversity of feedstocks,such as agricultural and forest residues,industrial by-products as well as municipal wastes,endows BCs different chemical compositions and structures.Woody and herbaceous BCs usually have higher carbon contents,larger surface areas and strong aromaticity,which is in favor of the organic contaminant removal.Driven by the desire of more cost-effective materials,several types of biochar-based hybrid materials,such as magnetic BC composites(MBC),nanometal/nanometallic oxides/hydroxide BC composites and layered nanomaterial-coated BCs,as well as physically/chemically activated BCs,have also been developed.With the help of foreign materials,these types of hybrid BCs have excellent capacities to remove a wide range of organic contaminants,including organic dyestuff,phenols and chemical intermediates,as well as pharmaceutically active compounds,from aquatic solutions.Depending on the different types of biochar-based materials,organic contaminants can be removed by different mechanisms,such as physical adsorption,electrostatic interaction,π-πinteraction and Fenton process,as well as photocatalytic degradation.In summary,the low cost,tunable surface chemistry and excellent physical-chemical properties of BCs allow it to be a potential material in organic contaminant removal.The combination of BCs with foreign materials endows BCs more functionalities and broader development opportunities.Considering the urgent demand of practical wastewater treatment,we展开更多
基金supported by the National Natural Science Foundation of China(51602207,21433007,51320105001,21573170)the Self-determined and Innovative Research Funds of SKLWUT(2017-ZD-4,2016-KF-17)the Natural Science Foundation of Hubei Province of China(2015CFA001)~~
文摘TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the reaction mechanism of Z‐scheme photocatalysts,recent research progress in the application of TiO2‐based Z‐scheme photocatalysts,and improved methods for photocatalytic performance enhancement are explored.Their applications,including water splitting,CO2reduction,decomposition of volatile organic compounds,and degradation of organic pollutants,are also described.The main factors affecting the photocatalytic performance of TiO2‐based Z‐scheme photocatalysts,such as pH,conductive medium,cocatalyst,architecture,and mass ratio,are discussed.Concluding remarks are presented,and some suggestions for the future development of TiO2‐based Z‐scheme photocatalysts are highlighted.
基金supported by Xiamen University Malaysia Research Fund (XMUMRF/2019-C3/IENG/0013)financial assistance and faculty start-up grants/supports from Xiamen University~~
文摘As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemical, graphitic carbon nitride (g-C3N4) has become research hotspots in the community. However, g-C3N4 photocatalyst still suffers from many problems, resulting in unsatisfactory photocatalytic activity such as low specific surface area, high charge recombination and insufficient visible light utilization. Since 2009, g-C3N4-based heterostructures have attracted the attention of scientists worldwide for their greatly enhanced photocatalytic performance. Overall, this review summarizes the recent advances of g-C3N4-based nanocomposites modified with transition metal sulfide (TMS), including (1) preparation of pristine g-C3N4,(2) modification strategies of g-C3N4,(3) design principles of TMS-modified g-C3N4 heterostructured photocatalysts, and (4) applications in energy conversion. What is more, the characteristics and transfer mechanisms of each classification of the metal sulfide heterojunction system will be critically reviewed, spanning from the following categories:(1) Type I heterojunction,(2) Type II heterojunction,(3) p-n heterojunction,(4) Schottky junction and (5) Z-scheme heterojunction. Apart from that, the application of g-C3N4-based heterostructured photocatalysts in H2 evolution, CO2 reduction, N2 fixation and pollutant degradation will also be systematically presented. Last but not least, this review will conclude with invigorating perspectives, limitations and prospects for further advancing g-C3N4-based heterostructured photocatalysts toward practical benefits for a sustainable future.
基金CSIR-CSMCRI communication No.160/2016funding through Network Project on "Waste to Wealth-Waste Plastics (W2W)" (Project No: CSC-0120)
文摘The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxidation processes（AOP）have been focused for removal of dye from waste water due to their advantages such as ecofriendly,economic and capable to degrade many dyes or organic pollutant present in water.Photocatalysis is one of the advance oxidation processes,mainly carried out under irradiation of light and suitable photocatalytic materials.The photocatalytic activity of the photocatalytic materials mainly depends on the band gap,surface area,and generation of electron–hole pair for degradation dyes present in water.It has been observed that the surface area plays a major role in photocatalytic degradation of dyes,by providing higher surface area,which leads to the higher adsorption of dye molecule on the surface of photocatalyst and enhances the photocatalytic activity.This present review discusses the synergic effect of adsorption of dyes on the photocatalytic efficiency of various nanostructured high surface area photocatalysts.In addition,it also provides the properties of the water polluting dyes,their mechanism and various photocatalytic materials;and their morphology used for the dye degradation under irradiation of light along with the future prospects of highly adsorptive photocatalytic material and their application in photocatalytic removal of dye from waste water.
基金support from the National Key Research and Development Program of China(2017YFA0207002)the National Natural Science Foundation of China(21836001,21607042)the Fundamental Research Funds for the Central Universities(2018ZD11,2018MS114).
文摘As a class of famous carbon materials,biochars(BCs)and their derivative materials with excellent physicochemical properties and diversified functionalities present great potential in wastewater treatment fields.This review focuses on the latest development in reported biochar-based materials as superior adsorbents or catalysts for removing harmful organic contaminants from wastewater.The construction and properties of biochar-based materials are briefly introduced at the beginning.As one of the major factors affecting the properties of BCs,the wide diversity of feedstocks,such as agricultural and forest residues,industrial by-products as well as municipal wastes,endows BCs different chemical compositions and structures.Woody and herbaceous BCs usually have higher carbon contents,larger surface areas and strong aromaticity,which is in favor of the organic contaminant removal.Driven by the desire of more cost-effective materials,several types of biochar-based hybrid materials,such as magnetic BC composites(MBC),nanometal/nanometallic oxides/hydroxide BC composites and layered nanomaterial-coated BCs,as well as physically/chemically activated BCs,have also been developed.With the help of foreign materials,these types of hybrid BCs have excellent capacities to remove a wide range of organic contaminants,including organic dyestuff,phenols and chemical intermediates,as well as pharmaceutically active compounds,from aquatic solutions.Depending on the different types of biochar-based materials,organic contaminants can be removed by different mechanisms,such as physical adsorption,electrostatic interaction,π-πinteraction and Fenton process,as well as photocatalytic degradation.In summary,the low cost,tunable surface chemistry and excellent physical-chemical properties of BCs allow it to be a potential material in organic contaminant removal.The combination of BCs with foreign materials endows BCs more functionalities and broader development opportunities.Considering the urgent demand of practical wastewater treatment,we
