We prepared the Fe3O4/g‐C3N4nanoparticles(NPs)through a simple electrostatic self‐assembly method with a3:97weight ratio to investigate their Fenton,photo‐Fenton and oxidative functionalities besides photocatalytic...We prepared the Fe3O4/g‐C3N4nanoparticles(NPs)through a simple electrostatic self‐assembly method with a3:97weight ratio to investigate their Fenton,photo‐Fenton and oxidative functionalities besides photocatalytic functionality.We observed an improvement of the Fenton and photo‐Fenton activities of the Fe3O4/g‐C3N4nanocomposites.This improvement was attributed to efficient charge transfer between Fe3O4and g‐C3N4at the heterojunctions,inhibition of electron‐hole recombination,a high surface area,and stabilization of Fe3O4against leaching by the hydrophobic g‐C3N4.The obtained NPs showed a higher degradation potential for rhodamine B(RhB)dye than those of Fe3O4and g‐C3N4.As compared to photocatalysis,the efficiency of RhB degradation in the Fenton and photo‐Fenton reactions was increased by20%and90%,respectively.Additionally,the horseradish peroxidase(HRP)activity of the prepared nanomaterials was studied with3,3,5,5‐tetramethylbenzidinedihydrochloride(TMB)as a substrate.Dopamine oxidation was also examined.Results indicate that Fe3O4/g‐C3N4nanocomposites offers more efficient degradation of RhB dye in a photo‐Fenton system compared with regular photocatalytic degradation,which requires a long time.Our study also confirmed that Fe3O4/g‐C3N4nanocomposites can be used as a potential material for mimicking HRP owing to its high affinity for TMB.These findings suggest good potential for applications in biosensing and as a catalyst in oxidation reactions.展开更多
以片状g-C3N4、六水三氯化铁、柠檬酸三钠和尿素为原料,聚丙烯酰胺为稳定剂,采用水热法制备Fe3O4/g-C3N4复合材料并作为过硫酸钠(PS)降解罗丹明B(RhB)的活化剂。通过XRD、SEM、EDS、FT-IR对样品结构、形貌与组成进行表征。考察Fe3O4与g-...以片状g-C3N4、六水三氯化铁、柠檬酸三钠和尿素为原料,聚丙烯酰胺为稳定剂,采用水热法制备Fe3O4/g-C3N4复合材料并作为过硫酸钠(PS)降解罗丹明B(RhB)的活化剂。通过XRD、SEM、EDS、FT-IR对样品结构、形貌与组成进行表征。考察Fe3O4与g-C3N4的质量比、活化剂质量、PS质量、溶液pH等对Fe3O4/g-C3N4活化PS降解RhB效果的影响。结果表明,与g-C3N4复合有效提高了Fe3O4的分散性和活化性能;在Fe3O4与g-C3N4质量比为3∶4、Fe3O4/g-C3N4质量为50 mg、PS质量为20 mg、RhB溶液pH为2.1时,反应120 min RhB的降解率达到100%。Fe3O4/g-C3N4可用磁铁进行分离回收,循环使用5次,活化PS去除RhB降解率仍达95.5%。展开更多
Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and charact...Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and characterized by powder X‐ray diffraction,Fourier transform infrared spectroscopy,thermogravimetric analysis,transmission electron microscopy,UV‐visible diffuse‐reflectance spectrometry,and photoluminescence emission spectrometry.The photocatalytic activities of the series of MG‐x heterojunctions toward Cr(VI)reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight.The influence of different organic compounds(ethanol,citric acid,oxalic acid,and diclofenac sodium)as hole scavengers and the pH values(2,3,4,6,and 8)on the photocatalytic activities of the series of MG‐x heterojunctions was investigated.MG‐20%showed superior photocatalytic Cr(VI)reduction and diclofenac sodium degradation performance than did the individual MIL‐100(Fe)and g‐C3N4 because of the improved separation of photoinduced electron‐hole charges,which was clarified via photoluminescence emission and electrochemical data.Moreover,the MG‐x exhibited good reusability and stability after several runs.展开更多
The novel polyoxometalate, 32[Mo8ⅣMo4ⅤV2ⅣO38(PO4)], was synthesized and characterized by elementary analysis, EPR, IR spectra and X ray diffraction. The compoundcrystallizes in triclinic system, space group with a=...The novel polyoxometalate, 32[Mo8ⅣMo4ⅤV2ⅣO38(PO4)], was synthesized and characterized by elementary analysis, EPR, IR spectra and X ray diffraction. The compoundcrystallizes in triclinic system, space group with a= 1.41999(2)nm, b=1.43467(2)nm, c=1.694610(10)nm, α=95.7250(10)°, β=92.2110(10)°, γ=92.6060(10)°, V=3.42829(7)nm3, Z=2, Dc=2.388g·cm-3, Mr=2465.10g·mol-1, μ=2.489mm-1, F(000)=2388, R1=0.0584, wR2=0.1461, S=1.164. The heteropolyanion is a bi capped pseudo Keggin complex. CCDC: 186645.展开更多
Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are ha...Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are hampered by the shuttle effect of soluble lithium polysulfides(LPS),which results in low cycle stability.Herein,a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C3 N4(t-C3 N4)embedded with Fe304 nanospheres.t-C3 N4 exhibits high surface area and strong anchoring of LPS,and the Fe3 O4/t-C3 N4 accelerates the anchoring of LPS and improves the electronic pathways.The combination of these materials leads to remarkable battery performance with 400%improvement in a specific capacity and a low capacity decay per cycle of 0.02%at 2 C over 1000 cycles,and stable cycling at 6.4 mg cm-2 for high-sulfur-loading cathode.展开更多
Exfoliation of bulk graphitic carbon nitride(g‐C3N4)into two‐dimensional(2D)nanosheets is one of the effective strategies to improve its photocatalytic properties so that the 2D g‐C3N4 nanosheets(CN)have larger spe...Exfoliation of bulk graphitic carbon nitride(g‐C3N4)into two‐dimensional(2D)nanosheets is one of the effective strategies to improve its photocatalytic properties so that the 2D g‐C3N4 nanosheets(CN)have larger specific surface areas and more reaction sites.In addition,poly‐o‐phenylenediamine(PoPD)can improve the electrical conductivity and photocatalytic activity of semiconductor materials.Here,the novel efficient composite PoPD/AgCl/g‐C3N4 nanosheets was first synthesized by a precipitation reaction and the photoinitiated polymerization approach.The obtained photocatalysts have larger specific surface areas and could achieve better visible‐light response.However,silver chloride(AgCl)is susceptible to agglomeration and photocorrosion.The PoPD/AgCl/CN composite exhibits an extremely high photocurrent density,which is three times that of CN.Obviously enhanced photocatalytic activities of PoPD/AgCl/g‐C3N4 are revealed through the photodegradation of tetracycline.The stability of PoPD/AgCl/CN is demonstrated based on four cycles of experiments that reveal that the degradation rate only decreases slightly.Furthermore,.O2^-and h+are the main active species,which are confirmed through a trapping experiment and ESR spin‐trap technique.Therefore,the prepared PoPD/AgCl/CN can be considered as a stable photocatalyst,in which PoPD is added as a charge carrier and acts a photosensitive protective layer on the surface of the AgCl particles.This provides a new technology for preparing highly stable composite photocatalysts that can effectively deal with environmental issues.展开更多
The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic syste...The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic systems focused on the utilization of the ultraviolet light but ignored the visible light generated by high voltage discharge.Graphitic carbon nitride(g‐C3N4),a metal‐free semiconductor that exhibits high chemical stability,can utilize both the ultraviolet and visible light from high voltage discharge.However,the synergistic system of NTP and g‐C3N4 has been researched little.In this paper,the effect of NTP generated by dielectric barrier discharge(DBD)on g‐C3N4 is studied by comparing the photocatalytic activities,the surface physical structure and the surface chemical characteristics of pristine and plasma treated g‐C3N4.Experimental results indicate that the DBD plasma can change the physical structure and the chemical characteristics and to further affect the photocatalytic activity of g‐C3N4.The effect of NTP on g‐C3N4 is associated with the discharge intensity and the discharge time.For a long time scale,the effect of NTP on g‐C3N4 photocatalysts presents a periodic change trend.展开更多
The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyan...The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyandiamide as the precursor and Fe3+doped in this study.The composite catalysts were characterized by XRD,SEM,FT-IR,XPS and photocurrent measurements.Close interaction occurred between Fe2O3 and nitrogen deficient g-C3N4-x,more photogenerated electrons were created and effectively separated from the holes,resulting in a decrease of photocarrier recombination,and thus enhancing the photocurrent.Photocatalytic performance experiments showed that Fe2O3/nitrogen deficient g-C3N4-x could utilize lowenergy visible light more efficiently than pure g-C3N4,and the removal rate was 92%in 60 minutes.展开更多
The photocatalytic reduction of aqueous Cr(VI)to Cr(III)was preliminarily studied using porousg‐C3N4as a photocatalyst under acidic conditions.The observed synergistic photocatalytic effect ofporous g‐C3N4on a Cr(VI...The photocatalytic reduction of aqueous Cr(VI)to Cr(III)was preliminarily studied using porousg‐C3N4as a photocatalyst under acidic conditions.The observed synergistic photocatalytic effect ofporous g‐C3N4on a Cr(VI)/4‐chlorophenol(4‐CP)composite pollution system was further studiedunder different pH conditions.Compared with single‐component photocatalytic systems for Cr(VI)reduction or4‐CP degradation,the Cr(VI)reduction efficiency and4‐CP degradation efficiency weresimultaneously improved in the Cr(VI)/4‐CP composite pollution system.The synergistic photocatalyticeffect in the Cr(VI)/4‐CP composite pollution system can be attributed to the acceleratedredox reaction between dichromate and4‐CP by electron transfer with porous g‐C3N4.展开更多
基金supported by the National Natural Science Foundation of China(51572253,21771171)Scientific Research Grant of Hefei Science Center of CAS(2015SRG-HSC048)+1 种基金cooperation between NSFC and Netherlands Organization for Scientific Research(51561135011)CAS-TWAS Scholarship Program~~
文摘We prepared the Fe3O4/g‐C3N4nanoparticles(NPs)through a simple electrostatic self‐assembly method with a3:97weight ratio to investigate their Fenton,photo‐Fenton and oxidative functionalities besides photocatalytic functionality.We observed an improvement of the Fenton and photo‐Fenton activities of the Fe3O4/g‐C3N4nanocomposites.This improvement was attributed to efficient charge transfer between Fe3O4and g‐C3N4at the heterojunctions,inhibition of electron‐hole recombination,a high surface area,and stabilization of Fe3O4against leaching by the hydrophobic g‐C3N4.The obtained NPs showed a higher degradation potential for rhodamine B(RhB)dye than those of Fe3O4and g‐C3N4.As compared to photocatalysis,the efficiency of RhB degradation in the Fenton and photo‐Fenton reactions was increased by20%and90%,respectively.Additionally,the horseradish peroxidase(HRP)activity of the prepared nanomaterials was studied with3,3,5,5‐tetramethylbenzidinedihydrochloride(TMB)as a substrate.Dopamine oxidation was also examined.Results indicate that Fe3O4/g‐C3N4nanocomposites offers more efficient degradation of RhB dye in a photo‐Fenton system compared with regular photocatalytic degradation,which requires a long time.Our study also confirmed that Fe3O4/g‐C3N4nanocomposites can be used as a potential material for mimicking HRP owing to its high affinity for TMB.These findings suggest good potential for applications in biosensing and as a catalyst in oxidation reactions.
文摘以片状g-C3N4、六水三氯化铁、柠檬酸三钠和尿素为原料,聚丙烯酰胺为稳定剂,采用水热法制备Fe3O4/g-C3N4复合材料并作为过硫酸钠(PS)降解罗丹明B(RhB)的活化剂。通过XRD、SEM、EDS、FT-IR对样品结构、形貌与组成进行表征。考察Fe3O4与g-C3N4的质量比、活化剂质量、PS质量、溶液pH等对Fe3O4/g-C3N4活化PS降解RhB效果的影响。结果表明,与g-C3N4复合有效提高了Fe3O4的分散性和活化性能;在Fe3O4与g-C3N4质量比为3∶4、Fe3O4/g-C3N4质量为50 mg、PS质量为20 mg、RhB溶液pH为2.1时,反应120 min RhB的降解率达到100%。Fe3O4/g-C3N4可用磁铁进行分离回收,循环使用5次,活化PS去除RhB降解率仍达95.5%。
基金supported by the National Natural Science Foundation of China(51578034,51878023)the Great Wall Scholars Training Program Project of Beijing Municipality Universities(CIT&TCD20180323)+3 种基金the Project of Construction of Innovation Teams and Teacher Career Development for Universities and Colleges Under Beijing Municipality(IDHT20170508)the Beijing Talent Project(2017A38)the Fundamental Research Funds for Beijing Universities(X18075/X18076/X18124/X18125/X18276)the Scientific Research Foundation of Beijing University of Civil Engineering and Architecture(KYJJ2017033/KYJJ2017008)~~
文摘Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and characterized by powder X‐ray diffraction,Fourier transform infrared spectroscopy,thermogravimetric analysis,transmission electron microscopy,UV‐visible diffuse‐reflectance spectrometry,and photoluminescence emission spectrometry.The photocatalytic activities of the series of MG‐x heterojunctions toward Cr(VI)reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight.The influence of different organic compounds(ethanol,citric acid,oxalic acid,and diclofenac sodium)as hole scavengers and the pH values(2,3,4,6,and 8)on the photocatalytic activities of the series of MG‐x heterojunctions was investigated.MG‐20%showed superior photocatalytic Cr(VI)reduction and diclofenac sodium degradation performance than did the individual MIL‐100(Fe)and g‐C3N4 because of the improved separation of photoinduced electron‐hole charges,which was clarified via photoluminescence emission and electrochemical data.Moreover,the MG‐x exhibited good reusability and stability after several runs.
文摘The novel polyoxometalate, 32[Mo8ⅣMo4ⅤV2ⅣO38(PO4)], was synthesized and characterized by elementary analysis, EPR, IR spectra and X ray diffraction. The compoundcrystallizes in triclinic system, space group with a= 1.41999(2)nm, b=1.43467(2)nm, c=1.694610(10)nm, α=95.7250(10)°, β=92.2110(10)°, γ=92.6060(10)°, V=3.42829(7)nm3, Z=2, Dc=2.388g·cm-3, Mr=2465.10g·mol-1, μ=2.489mm-1, F(000)=2388, R1=0.0584, wR2=0.1461, S=1.164. The heteropolyanion is a bi capped pseudo Keggin complex. CCDC: 186645.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2019R1A2C1003594 and NRF-2019R1A2C1003551)。
文摘Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are hampered by the shuttle effect of soluble lithium polysulfides(LPS),which results in low cycle stability.Herein,a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C3 N4(t-C3 N4)embedded with Fe304 nanospheres.t-C3 N4 exhibits high surface area and strong anchoring of LPS,and the Fe3 O4/t-C3 N4 accelerates the anchoring of LPS and improves the electronic pathways.The combination of these materials leads to remarkable battery performance with 400%improvement in a specific capacity and a low capacity decay per cycle of 0.02%at 2 C over 1000 cycles,and stable cycling at 6.4 mg cm-2 for high-sulfur-loading cathode.
基金supported by the National Natural Science Foundation of China(21576125,21776117)the China Postdoctoral Science Foundation(2017M611716,2017M611734)+1 种基金the Six talent peaks project of Jiangsu Province(XCL-014)the Zhenjiang Science&Technology Program(SH2016012)~~
文摘Exfoliation of bulk graphitic carbon nitride(g‐C3N4)into two‐dimensional(2D)nanosheets is one of the effective strategies to improve its photocatalytic properties so that the 2D g‐C3N4 nanosheets(CN)have larger specific surface areas and more reaction sites.In addition,poly‐o‐phenylenediamine(PoPD)can improve the electrical conductivity and photocatalytic activity of semiconductor materials.Here,the novel efficient composite PoPD/AgCl/g‐C3N4 nanosheets was first synthesized by a precipitation reaction and the photoinitiated polymerization approach.The obtained photocatalysts have larger specific surface areas and could achieve better visible‐light response.However,silver chloride(AgCl)is susceptible to agglomeration and photocorrosion.The PoPD/AgCl/CN composite exhibits an extremely high photocurrent density,which is three times that of CN.Obviously enhanced photocatalytic activities of PoPD/AgCl/g‐C3N4 are revealed through the photodegradation of tetracycline.The stability of PoPD/AgCl/CN is demonstrated based on four cycles of experiments that reveal that the degradation rate only decreases slightly.Furthermore,.O2^-and h+are the main active species,which are confirmed through a trapping experiment and ESR spin‐trap technique.Therefore,the prepared PoPD/AgCl/CN can be considered as a stable photocatalyst,in which PoPD is added as a charge carrier and acts a photosensitive protective layer on the surface of the AgCl particles.This provides a new technology for preparing highly stable composite photocatalysts that can effectively deal with environmental issues.
文摘The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic systems focused on the utilization of the ultraviolet light but ignored the visible light generated by high voltage discharge.Graphitic carbon nitride(g‐C3N4),a metal‐free semiconductor that exhibits high chemical stability,can utilize both the ultraviolet and visible light from high voltage discharge.However,the synergistic system of NTP and g‐C3N4 has been researched little.In this paper,the effect of NTP generated by dielectric barrier discharge(DBD)on g‐C3N4 is studied by comparing the photocatalytic activities,the surface physical structure and the surface chemical characteristics of pristine and plasma treated g‐C3N4.Experimental results indicate that the DBD plasma can change the physical structure and the chemical characteristics and to further affect the photocatalytic activity of g‐C3N4.The effect of NTP on g‐C3N4 is associated with the discharge intensity and the discharge time.For a long time scale,the effect of NTP on g‐C3N4 photocatalysts presents a periodic change trend.
基金Supported by the Fuling Shale Gas Environmental Exploration Technology of National Science and Technology Special Project(No.2016ZX05060)the Demonstration of Integrated Management of Rocky Desertification and Enhancement of Ecological Service Function in Karst Peak-cluster Depression(No.2016YFC0502400)National Natural Science Foundation of China(No.51709254)
文摘The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyandiamide as the precursor and Fe3+doped in this study.The composite catalysts were characterized by XRD,SEM,FT-IR,XPS and photocurrent measurements.Close interaction occurred between Fe2O3 and nitrogen deficient g-C3N4-x,more photogenerated electrons were created and effectively separated from the holes,resulting in a decrease of photocarrier recombination,and thus enhancing the photocurrent.Photocatalytic performance experiments showed that Fe2O3/nitrogen deficient g-C3N4-x could utilize lowenergy visible light more efficiently than pure g-C3N4,and the removal rate was 92%in 60 minutes.
基金supported by the National Natural Science Foundation of China(51568049,51468043,21366024,21665018)the National Science Fund for Excellent Young Scholars(51422807)+2 种基金the Natural Science Foundation of Jiangxi Province,China(20161BAB206118,20171ACB21035)the Distinguished Youth Science Fund of Jiangxi Province(20162BCB23043)the Natural Science Foundation of Jiangxi Provincial Department of Education,China(GJJ14515)~~
文摘The photocatalytic reduction of aqueous Cr(VI)to Cr(III)was preliminarily studied using porousg‐C3N4as a photocatalyst under acidic conditions.The observed synergistic photocatalytic effect ofporous g‐C3N4on a Cr(VI)/4‐chlorophenol(4‐CP)composite pollution system was further studiedunder different pH conditions.Compared with single‐component photocatalytic systems for Cr(VI)reduction or4‐CP degradation,the Cr(VI)reduction efficiency and4‐CP degradation efficiency weresimultaneously improved in the Cr(VI)/4‐CP composite pollution system.The synergistic photocatalyticeffect in the Cr(VI)/4‐CP composite pollution system can be attributed to the acceleratedredox reaction between dichromate and4‐CP by electron transfer with porous g‐C3N4.
