Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites whi...Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites which possess unsaturated titanium–oxo clusters,mesoporous structure,and intimate interface were successfully constructed via an in-situ distilled water-etched route.The X-ray photoelectron spectroscopy (XPS) measurements indicated strong electronic interaction between TiO_(2)and NH_(2)-MIL-125(Ti),confirming the formation of TiO 2@NH_(2)-MIL-125(Ti) nanocomposite.Photoelectrochemical and thermodynamics measurements showed that TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposites have improved charge separation efficient and decreased transfer resistance of the carriers within the heterojunction interfaces,which facilitates the photoexcited electrons transfer and reduction of the Cr(VI) species.Therefore,the optimal TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposite demonstrated superior performance compared to NH_(2)-MIL-125(Ti) and NH_(2)-MIL-125(Ti) derived TiO_(2).Based on the free radical trapping experiment and electron paramagnetic resonance (EPR) measurements,a possible type-II scheme was proposed for the enhanced photocatalytic activity over the TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposite.展开更多
Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise appro...Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise approach.In this work,a novel NH2-MIL-125(Ti)/Bi2WO6 composite was constructed via self-assembly growing Bi2WO6 nanosheets on NH2-MIL-125(Ti)material.The characterization results demonstrated that NH2-MIL-125(Ti)was successfully incorporated into Bi2WO6 and the photoexcited carriers could be efficiently separated and transferred between the two components.NH2-MIL-125(Ti)/Bi2WO6 composites displayed enhanced photocatalytic activity for the removal of rhodamine B(RhB)and tetracycline(TC)under visible light irradiation,and the optimal weight ratio of NH2-MIL-125(Ti)was determined to be 7 wt%.The introduction of NH2-MIL-125(Ti)into Bi2WO6 could raise the absorption of visible light,accelerate the separation and transfer of charge carriers,and boost photocatalytic activity.This research presents a wide range of possibilities for the further development of novel composites in the field of environment purification.展开更多
One key strategy to enhance photocatalytic performance is to improve the transfer and separation efficiency of photogenerated carriers by building optimized heterojunctions.Herein,novel Bi_(4)O_5Br_(2)/NH_(2)-MIL-125(...One key strategy to enhance photocatalytic performance is to improve the transfer and separation efficiency of photogenerated carriers by building optimized heterojunctions.Herein,novel Bi_(4)O_5Br_(2)/NH_(2)-MIL-125(Ti)Z-scheme heterojunctions are fabricated and used as photocatalysts for organic pollutant photodegradation.The NH_(2)-MIL-125(Ti)nanosheets are exfoliated via a self-developed alkali solution stripping approach and then uniformly decorated on Bi_(4)O_(5)Br_(2).The as-prepared Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)presents more than 90%degradation of various pollutants,outperforming the counterpart individual ones.The various characterization results suggest that the enhanced degradation rate is due to the more intimate face-to-face interfacial contact of the lamellar Z-scheme heterojunction materials,in which the migration path of carriers from the material's interior to the surface can be reduced,in turn enhancing migration efficiency and separation capability significantly.A possible photocatalytic reaction mechanism is proposed based on the photoelectric behaviors,radical trapping experiments and liquid chromatography mass spectrometry analysis.This work promotes the development of new photocatalytic materials for heterojunctions with face-to-face interfacial contacts,as well as the effective purification of wastewater in environmental remediation.展开更多
NH_(2)-MIL-125(Ti)is a Ti-MOFs(MOFs:metal-organic frameworks)with high adsorption properties and is therefore widely used for wastewater purification.However,the powdered MOF material suffers from the disadvantages of...NH_(2)-MIL-125(Ti)is a Ti-MOFs(MOFs:metal-organic frameworks)with high adsorption properties and is therefore widely used for wastewater purification.However,the powdered MOF material suffers from the disadvantages of being difficult to separate and being potentially wasted due to easy agglomeration,which limits its application in practical applications.Here,a mesoporous Ti-MOF/polymer(PEG,PVA,and PAM)monolithic material was prepared by freeze casting in liquid nitrogen(-196℃)as an adsorbent for wastewater remediation.The composites could be easily picked up with tweezers and used for recovery tests.Characterization results such as XRD,BET,FT-IR,and SEM proved the successful synthesis of Ti-MOF/polymer.Adsorption tests using 100 mg/L methylene blue(MB)simulated wastewater showed that the Ti-MOF/PEG monolithic material had the best adsorption capacity.The order of adsorption was Ti-MOF@PEG10(747.4 mg/g)>Ti-MOF@PVA10(687.4 mg/g)>Ti-MOF@PAM10(633.7 mg/g)>NH_(2)-MIL-125(Ti)(571.4 mg/g).The effects of polymer dosage,different pollutants(methylene blue,methyl orange,indigo,actual textile wastewater),pH,anions,and cations on the adsorption effect of Ti-MOF/polymer were also investigated.It was demonstrated that all the above pollutants were well adsorbed by this Ti-MOF/polymer in the pH range 3-9.The adsorption isotherms and kinetic data are fully consistent with the Langmuir and pseudo-secondary models.This suggests that the adsorption between the pollutant and the adsorbent is a chemical interaction.Thermodynamic studies indicate that the adsorption process is exothermic and spontaneous.This work provides the potential methods to fabricate Ti-MOF/polymer monolith to avoid the pollution from powdery adsorbents that could be practical applications.展开更多
Infections caused by bacteria threaten human health,so how to effectively kill bacteria is an urgent problem.We therefore synthesized a NH_(2)-MIL-125-GO-Pt ternary composite heterojunction with graphene oxide(GO)and ...Infections caused by bacteria threaten human health,so how to effectively kill bacteria is an urgent problem.We therefore synthesized a NH_(2)-MIL-125-GO-Pt ternary composite heterojunction with graphene oxide(GO)and platinum(Pt)nanoparticles co-doped with metal-organic framework(NH_(2)-MIL-125)for use in photocatalytic and photothermal synergistic disinfection under white light irradiation.Due to the good conductivity of GO and the Schottky junction between Pt and MOF,the doping of GO and Pt will effectively separate and transfer the photogenerated electron-hole pairs generated by NH_(2)-MIL-125,thereby effectively improving the photocatalytic efficiency of NH_(2)-MIL-125.Meanwhile,NH_(2)-MIL-125-GO-Pt has good photothermal effect under white light irradiation.Therefore,the NH_(2)-MIL-125-GO-Pt composite can be used for effective sterilization.The antibacterial efficiency of NH_(2)-MIL-125-GO-Pt against Staphylococcus aureus and Escherichia coli were as high as 99.94%and 99.12%,respectively,within 20 min of white light irradiation.In vivo experiments showed that NH_(2)-MIL-125-GO-Pt could effectively kill bacteria and promote wound healing.This work brings new insights into the use of NH_(2)-MIL-125-based photocatalyst materials for rapid disinfection of environments with pathogenic microorganisms.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 61204078, 21671059, and 21877027)the Program for Innovative Research Team (in Science and Technology) of Henan Normal University (No. 2022TD03)+1 种基金the Henan Science and Technology Program (No. 21B150005)the Scientific and Technological Innovation Team of Henan Normal University (No. 2022TD03)。
文摘Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites which possess unsaturated titanium–oxo clusters,mesoporous structure,and intimate interface were successfully constructed via an in-situ distilled water-etched route.The X-ray photoelectron spectroscopy (XPS) measurements indicated strong electronic interaction between TiO_(2)and NH_(2)-MIL-125(Ti),confirming the formation of TiO 2@NH_(2)-MIL-125(Ti) nanocomposite.Photoelectrochemical and thermodynamics measurements showed that TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposites have improved charge separation efficient and decreased transfer resistance of the carriers within the heterojunction interfaces,which facilitates the photoexcited electrons transfer and reduction of the Cr(VI) species.Therefore,the optimal TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposite demonstrated superior performance compared to NH_(2)-MIL-125(Ti) and NH_(2)-MIL-125(Ti) derived TiO_(2).Based on the free radical trapping experiment and electron paramagnetic resonance (EPR) measurements,a possible type-II scheme was proposed for the enhanced photocatalytic activity over the TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposite.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21476098,21471069 and 21576123)and Jiangsu University Scientific Research Funding(No.11JDG0146).
文摘Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise approach.In this work,a novel NH2-MIL-125(Ti)/Bi2WO6 composite was constructed via self-assembly growing Bi2WO6 nanosheets on NH2-MIL-125(Ti)material.The characterization results demonstrated that NH2-MIL-125(Ti)was successfully incorporated into Bi2WO6 and the photoexcited carriers could be efficiently separated and transferred between the two components.NH2-MIL-125(Ti)/Bi2WO6 composites displayed enhanced photocatalytic activity for the removal of rhodamine B(RhB)and tetracycline(TC)under visible light irradiation,and the optimal weight ratio of NH2-MIL-125(Ti)was determined to be 7 wt%.The introduction of NH2-MIL-125(Ti)into Bi2WO6 could raise the absorption of visible light,accelerate the separation and transfer of charge carriers,and boost photocatalytic activity.This research presents a wide range of possibilities for the further development of novel composites in the field of environment purification.
基金financially supported by the National Natural Science Foundation of China(No.51302061)the Natural Science Foundation of Hebei province(Nos.E2014201076,E2020201021 and E2023201019)+3 种基金the Research Innovation Team of College of Chemistry and Environmental Science of Hebei University(No.hxkytd2102)Shenzhen Science and Technology Innovation Committee(No.JCYJ20200109141412308)Bintuan Science and Technology Program(Nos.2020DB002 and 2022DB009)CWO funding of Ghent University。
文摘One key strategy to enhance photocatalytic performance is to improve the transfer and separation efficiency of photogenerated carriers by building optimized heterojunctions.Herein,novel Bi_(4)O_5Br_(2)/NH_(2)-MIL-125(Ti)Z-scheme heterojunctions are fabricated and used as photocatalysts for organic pollutant photodegradation.The NH_(2)-MIL-125(Ti)nanosheets are exfoliated via a self-developed alkali solution stripping approach and then uniformly decorated on Bi_(4)O_(5)Br_(2).The as-prepared Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)presents more than 90%degradation of various pollutants,outperforming the counterpart individual ones.The various characterization results suggest that the enhanced degradation rate is due to the more intimate face-to-face interfacial contact of the lamellar Z-scheme heterojunction materials,in which the migration path of carriers from the material's interior to the surface can be reduced,in turn enhancing migration efficiency and separation capability significantly.A possible photocatalytic reaction mechanism is proposed based on the photoelectric behaviors,radical trapping experiments and liquid chromatography mass spectrometry analysis.This work promotes the development of new photocatalytic materials for heterojunctions with face-to-face interfacial contacts,as well as the effective purification of wastewater in environmental remediation.
基金the National Natural Science Foundation of China(No.21902118)
文摘NH_(2)-MIL-125(Ti)is a Ti-MOFs(MOFs:metal-organic frameworks)with high adsorption properties and is therefore widely used for wastewater purification.However,the powdered MOF material suffers from the disadvantages of being difficult to separate and being potentially wasted due to easy agglomeration,which limits its application in practical applications.Here,a mesoporous Ti-MOF/polymer(PEG,PVA,and PAM)monolithic material was prepared by freeze casting in liquid nitrogen(-196℃)as an adsorbent for wastewater remediation.The composites could be easily picked up with tweezers and used for recovery tests.Characterization results such as XRD,BET,FT-IR,and SEM proved the successful synthesis of Ti-MOF/polymer.Adsorption tests using 100 mg/L methylene blue(MB)simulated wastewater showed that the Ti-MOF/PEG monolithic material had the best adsorption capacity.The order of adsorption was Ti-MOF@PEG10(747.4 mg/g)>Ti-MOF@PVA10(687.4 mg/g)>Ti-MOF@PAM10(633.7 mg/g)>NH_(2)-MIL-125(Ti)(571.4 mg/g).The effects of polymer dosage,different pollutants(methylene blue,methyl orange,indigo,actual textile wastewater),pH,anions,and cations on the adsorption effect of Ti-MOF/polymer were also investigated.It was demonstrated that all the above pollutants were well adsorbed by this Ti-MOF/polymer in the pH range 3-9.The adsorption isotherms and kinetic data are fully consistent with the Langmuir and pseudo-secondary models.This suggests that the adsorption between the pollutant and the adsorbent is a chemical interaction.Thermodynamic studies indicate that the adsorption process is exothermic and spontaneous.This work provides the potential methods to fabricate Ti-MOF/polymer monolith to avoid the pollution from powdery adsorbents that could be practical applications.
基金the China National Funds for Distinguished Young Scientists(No.51925104)the National Natural Science Foundation of China(Nos.51871162,and 52173251).
文摘Infections caused by bacteria threaten human health,so how to effectively kill bacteria is an urgent problem.We therefore synthesized a NH_(2)-MIL-125-GO-Pt ternary composite heterojunction with graphene oxide(GO)and platinum(Pt)nanoparticles co-doped with metal-organic framework(NH_(2)-MIL-125)for use in photocatalytic and photothermal synergistic disinfection under white light irradiation.Due to the good conductivity of GO and the Schottky junction between Pt and MOF,the doping of GO and Pt will effectively separate and transfer the photogenerated electron-hole pairs generated by NH_(2)-MIL-125,thereby effectively improving the photocatalytic efficiency of NH_(2)-MIL-125.Meanwhile,NH_(2)-MIL-125-GO-Pt has good photothermal effect under white light irradiation.Therefore,the NH_(2)-MIL-125-GO-Pt composite can be used for effective sterilization.The antibacterial efficiency of NH_(2)-MIL-125-GO-Pt against Staphylococcus aureus and Escherichia coli were as high as 99.94%and 99.12%,respectively,within 20 min of white light irradiation.In vivo experiments showed that NH_(2)-MIL-125-GO-Pt could effectively kill bacteria and promote wound healing.This work brings new insights into the use of NH_(2)-MIL-125-based photocatalyst materials for rapid disinfection of environments with pathogenic microorganisms.