A stable PNIPAM/Fe_3O_4/g-C_3N_4 composite photocatalyst was designed and prepared by a thermal photoinitiation technology.The structure and properties of the materials were characterized and the composite photocataly...A stable PNIPAM/Fe_3O_4/g-C_3N_4 composite photocatalyst was designed and prepared by a thermal photoinitiation technology.The structure and properties of the materials were characterized and the composite photocatalyst was found to show good stability for tetracycline degradation.The sample not only retained the magnetic properties of Fe_3O_4,allowing it to be recycled,but its photocatalytic properties could also be changed by controlling the temperature of the reaction system.The degradation intermediate products of tetracycline were further investigated by MS.This work provides a new facile strategy for the development of intelligent and recyclable photocatalytic materials.展开更多
Fe_(2)O_(3)/Co_(3)O_(4)/NiO/NC nanosheets have been successfully prepared via a two-step annealing process of ternary metal coordination polymer. Attributing to the synergistic effects of the multiple metal oxides and...Fe_(2)O_(3)/Co_(3)O_(4)/NiO/NC nanosheets have been successfully prepared via a two-step annealing process of ternary metal coordination polymer. Attributing to the synergistic effects of the multiple metal oxides and the unique 2D nanosheet structure, the improved electrical conductivity and effective electron/ion transfer enables Fe_(2)O_(3)/Co_(3)O_(4)/NiO/NC electrode to exhibit excellent electrochemical properties with outstanding rate capacity and cycling stability. This work may pave the way to construct ternary metal oxide electrode material with an excellent electrochemical performance by introducing multiple metal oxides.展开更多
The low surface area,high recombination rate of photogenerated charge carriers,narrow visible range activity,and difficulty in the separation from cleaned solutions limit the wide application of g-C_(3)N_(4) as a phot...The low surface area,high recombination rate of photogenerated charge carriers,narrow visible range activity,and difficulty in the separation from cleaned solutions limit the wide application of g-C_(3)N_(4) as a photocatalyst.Herein,we have succeeded in developing a one-pot strategy to overcome the above-mentioned difficulties of g-C_(3)N_(4).The broadening of the visible-light response range and inducing magnetic nature to g-C_(3)N_(4) was succeeded by preparing a nanocomposite with Fe_(2)O_(3) via a facile solvothermal method.The preparation method additionally imparted layer exfoliation of g-C_(3)N_(4) as evident from the XRD patterns and TEM images.The strong interaction between the components is revealed from the XPS analysis.The broadened visible-light absorbance of Fe_(2)O_(3)/g-C_(3)N_(4) with a Z-scheme photocatalytic degradation mechanism is well evident from the UV-Vis DRS analysis and PL measurement of the composite with terephthalic acid.The active species of photocatalysis were further investigated using scavenging studies in methylene blue degradation that revealed hydroxyl radicals and holes as the major contributors to the activity of Fe_(2)O_(3)/g-C_(3)N_(4).展开更多
In this work,a comparative study of three frequently employed modification techniques to g-C_(3)N_(4)(CN)nanosheets for the photocatalytic degradation of metribuzin(MET)under visible-light irradiation has been carried...In this work,a comparative study of three frequently employed modification techniques to g-C_(3)N_(4)(CN)nanosheets for the photocatalytic degradation of metribuzin(MET)under visible-light irradiation has been carried out in detail.The modification methods were coupling TiO_(2)nanoparticles(TO)as electron acceptors,nano-sized Fe_(2)O_(3)(FO)to construct a Z-scheme nanocomposite,and phosphate(HP)modification to promote O_(2)adsorption.The steady-state and transient-state surface photovoltage spectra and transient photoluminescence(PL)spectra confirmed that all the three modification techniques enhanced the charge separation with prolonged lifetimes and presented degradation activities in the order of TO/CN[FO/CN[HP/CN.The TO/CN nanocomposite showed the highest photocatalytic activity for MET degradation,with a sixfold higher rate than bulk CN.Liquid chromatography–tandem mass spectrometry and radical trapping experiments indicated that the increased activity was related to the synergetic effect of two radicals(·O^(2-) and ·OH)involved in the photocatalytic degradation pathway,which was different from the·OH radical-dominated pathway of bulk CN.This work reveals the importance of charge separation and the influence of the radical pathway and provides guidance for the design of high-efficiency photocatalysts.展开更多
基金supported by the National Natural Science Foundation of China(31470434,21406090,21576124,21676124,21507047)the Project of Science and Technology Development Plan of Taicang(TC2015NY05)~~
文摘A stable PNIPAM/Fe_3O_4/g-C_3N_4 composite photocatalyst was designed and prepared by a thermal photoinitiation technology.The structure and properties of the materials were characterized and the composite photocatalyst was found to show good stability for tetracycline degradation.The sample not only retained the magnetic properties of Fe_3O_4,allowing it to be recycled,but its photocatalytic properties could also be changed by controlling the temperature of the reaction system.The degradation intermediate products of tetracycline were further investigated by MS.This work provides a new facile strategy for the development of intelligent and recyclable photocatalytic materials.
基金supported by the Natural Science Foundation of Guangdong Province(No.2020A1515010886)the Science and Technology Planning Project of Guangzhou(No.202102010373)。
文摘Fe_(2)O_(3)/Co_(3)O_(4)/NiO/NC nanosheets have been successfully prepared via a two-step annealing process of ternary metal coordination polymer. Attributing to the synergistic effects of the multiple metal oxides and the unique 2D nanosheet structure, the improved electrical conductivity and effective electron/ion transfer enables Fe_(2)O_(3)/Co_(3)O_(4)/NiO/NC electrode to exhibit excellent electrochemical properties with outstanding rate capacity and cycling stability. This work may pave the way to construct ternary metal oxide electrode material with an excellent electrochemical performance by introducing multiple metal oxides.
文摘The low surface area,high recombination rate of photogenerated charge carriers,narrow visible range activity,and difficulty in the separation from cleaned solutions limit the wide application of g-C_(3)N_(4) as a photocatalyst.Herein,we have succeeded in developing a one-pot strategy to overcome the above-mentioned difficulties of g-C_(3)N_(4).The broadening of the visible-light response range and inducing magnetic nature to g-C_(3)N_(4) was succeeded by preparing a nanocomposite with Fe_(2)O_(3) via a facile solvothermal method.The preparation method additionally imparted layer exfoliation of g-C_(3)N_(4) as evident from the XRD patterns and TEM images.The strong interaction between the components is revealed from the XPS analysis.The broadened visible-light absorbance of Fe_(2)O_(3)/g-C_(3)N_(4) with a Z-scheme photocatalytic degradation mechanism is well evident from the UV-Vis DRS analysis and PL measurement of the composite with terephthalic acid.The active species of photocatalysis were further investigated using scavenging studies in methylene blue degradation that revealed hydroxyl radicals and holes as the major contributors to the activity of Fe_(2)O_(3)/g-C_(3)N_(4).
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21971057 and U1805255)the Natural Science Foundation of Heilongjiang Province(Nos.YQ2019B006 and LH2020B012)+2 种基金the Postdoctoral Research Foundation of Heilongjiang Province(No.LBH-Q19052)the Outstanding Youth Fund of Heilongjiang University(No.JCL201901)the Basic Scientific Research Expenses of Colleges and Universities in Heilongjiang Province(No.2020-KYYWF-1008).
文摘In this work,a comparative study of three frequently employed modification techniques to g-C_(3)N_(4)(CN)nanosheets for the photocatalytic degradation of metribuzin(MET)under visible-light irradiation has been carried out in detail.The modification methods were coupling TiO_(2)nanoparticles(TO)as electron acceptors,nano-sized Fe_(2)O_(3)(FO)to construct a Z-scheme nanocomposite,and phosphate(HP)modification to promote O_(2)adsorption.The steady-state and transient-state surface photovoltage spectra and transient photoluminescence(PL)spectra confirmed that all the three modification techniques enhanced the charge separation with prolonged lifetimes and presented degradation activities in the order of TO/CN[FO/CN[HP/CN.The TO/CN nanocomposite showed the highest photocatalytic activity for MET degradation,with a sixfold higher rate than bulk CN.Liquid chromatography–tandem mass spectrometry and radical trapping experiments indicated that the increased activity was related to the synergetic effect of two radicals(·O^(2-) and ·OH)involved in the photocatalytic degradation pathway,which was different from the·OH radical-dominated pathway of bulk CN.This work reveals the importance of charge separation and the influence of the radical pathway and provides guidance for the design of high-efficiency photocatalysts.
