Good crystallinity can reduce the charge recombination centers caused by defects,whilst structures with strong polycondensation have high charge mobility,leading to more charge transfer to the material surface for rea...Good crystallinity can reduce the charge recombination centers caused by defects,whilst structures with strong polycondensation have high charge mobility,leading to more charge transfer to the material surface for reaction.Much effort has been put into the preparation of a highly efficient g-C_(3)N_(4) with defects to improve its application potential under the premise in high crystallinity.Hence,this review paper emphasizes the importance to balance the defect and crystallinity of g-C_(3)N_(4).In addition,detailed discussion on the relationship between defects and activity of g-C_(3)N_(4) was carried out based on its applications in environmental purification(e.g.,VOCs oxidation,NO_(x) oxidation,H_(2)O_(2) evolution,sterilization,pesticide oxidation)and energy conversion(H_(2) evolution,N_(2) fixation and CO_(2) reduction).Lastly,the challenge in developing more efficient defective g-C_(3)N_(4) photocatalytic materials is summarized.展开更多
This work uses thermal polymerization of urea nitrate,oxyacetic acid and urea as the raw material to prepare ultra-thin porous carbon nitride with carbon defects and C-O band(OA-UN-CN).Density functional theory(DFT)ca...This work uses thermal polymerization of urea nitrate,oxyacetic acid and urea as the raw material to prepare ultra-thin porous carbon nitride with carbon defects and C-O band(OA-UN-CN).Density functional theory(DFT)calculations showed OA-UN-CN had narrower band gap,faster electron transport and a new internal construction electric field.Additionally,the prepared OA-UN-CN significantly enhanced photocatalytic activation of peroxymonosulfate(PMS)due to enhanced light absorption performance and faster electron overflow.As the result,the OA-UN-CN/PMS could entirely degrade bisphenol A(BPA)within 30 min,where the photodegradation rate was 81.8 and 7.9 times higher than that of g-C_(3)N_(4)and OA-UN-CN,respectively.Beyond,the OA-UN-CN/PMS could likewise degrade other bisphenol pollutants and sodium lignosulfonate efficiently.We suggested possible photocatalytic degradation pathways accordingly and explored the toxicity of its degradation products.This work provides a new idea on the development of advanced photocatalytic oxidation processes for the treatment of bisphenol pollutants and lignin derivatives,via a metal-free photothermal-catalyst.展开更多
The photocatalytic activity of catalysts depends on the energy-harvesting ability and the separation or transport of photogenerated carriers.The light absorption capacity of graphitic carbon nitride(g-C_(3)N_(4))-base...The photocatalytic activity of catalysts depends on the energy-harvesting ability and the separation or transport of photogenerated carriers.The light absorption capacity of graphitic carbon nitride(g-C_(3)N_(4))-based composites can be enhanced by adjusting the surface plasmon resonance(SPR)of noble metal nanoparticles(e.g.,Cu,Au,and Pd)in the entire visible region.Adjustments can be carried out by varying the nanocomponents of the materials.The SPR of noble metals can enhance the local electromagnetic field and improve interband transition,and resonant energy transfer occurs from plasmonic dipoles to electron-hole pairs via near-field electromagnetic interactions.Thus,noble metals have emerged as relevant nanocomponents for g-C_(3)N_(4) used in CO_(2) photoreduction and water splitting.Herein,recent key advances in noble metals(either in single atom,cluster,or nanoparticle forms)and composite photocatalysts based on inorganic or organic nanocomponent-incorporated g-C_(3)N_(4) nanosheets are systematically discussed,including the applications of these photocatalysts,which exhibit improved photoinduced charge mobility in CO_(2) photoconversion and H2 production.Issues related to the different types of multi-nanocomponent heterostructures(involving Schottky junctions,Z-/S-scheme heterostructures,noble metals,and additional semiconductor nanocomponents)and the adjustment of dimensionality of heterostructures(by incorporating noble metal nanoplates on g-C_(3)N_(4) forming 2D/2D heterostructures)are explored.The current prospects and possible challenges of g-C_(3)N_(4) composite photocatalysts incorporated with noble metals(e.g.,Au,Pt,Pd,and Cu),particularly in water splitting,CO_(2) reduction,pollution degradation,and chemical conversion applications,are summarized.展开更多
光催化灭活是公认的控制病原微生物最具前景手段之一。本文以尿素和硫代巴比妥酸为起始原料,通过热聚合反应制备S掺杂g-C_(3)N_(4)(SCN),随后采用光还原法将Ag纳米粒负载于SCN表面获得新颖的可见光响应型Ag/SCN抗菌材料。对所制备纳米...光催化灭活是公认的控制病原微生物最具前景手段之一。本文以尿素和硫代巴比妥酸为起始原料,通过热聚合反应制备S掺杂g-C_(3)N_(4)(SCN),随后采用光还原法将Ag纳米粒负载于SCN表面获得新颖的可见光响应型Ag/SCN抗菌材料。对所制备纳米材料进行XRD、SEM、TEM、XPS及UV-Vis DRS表征,并深入探讨其在可见光下灭活大肠杆菌(E.coli)的性能和机制。结果表明,Ag纳米粒均匀且牢固地负载在SCN表面,纳米材料表现出显著增强的可见光响应能力。当负载量为6%时,Ag/SCN-6呈现出最佳的光催化灭菌活性,60 min内能够将6.2 lg CFU·mL^(-1)的E.coli全部灭活。自由基捕获实验结果表明,超氧自由基(·O-2)是灭活过程中最主要活性物种,它协同光生空穴(h+)和羟基自由基(·OH)主导了光催化抗菌的进程。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52370109)China Postdoctoral Science Foundation(2022M710830)+4 种基金Venture and Innovation Support Program for Chongqing Overseas Returnees(cx2022005)the Natural Science Foun-dation Project of CQ CSTC(CSTB2022NSCQ-MSX1267)Research Project of Chongqing Education Commission Foundation(KJQN201800826)Science and Technology Research Program of Chongqing Municipal Education Commission of China(KJZD-K202100801)Post-doctoral Program Funded by Chongqing,and Chongqing Technology and Business University,China(CXQT21023).
文摘Good crystallinity can reduce the charge recombination centers caused by defects,whilst structures with strong polycondensation have high charge mobility,leading to more charge transfer to the material surface for reaction.Much effort has been put into the preparation of a highly efficient g-C_(3)N_(4) with defects to improve its application potential under the premise in high crystallinity.Hence,this review paper emphasizes the importance to balance the defect and crystallinity of g-C_(3)N_(4).In addition,detailed discussion on the relationship between defects and activity of g-C_(3)N_(4) was carried out based on its applications in environmental purification(e.g.,VOCs oxidation,NO_(x) oxidation,H_(2)O_(2) evolution,sterilization,pesticide oxidation)and energy conversion(H_(2) evolution,N_(2) fixation and CO_(2) reduction).Lastly,the challenge in developing more efficient defective g-C_(3)N_(4) photocatalytic materials is summarized.
基金the National Natural Science Foundation of China(No.22076068,8111310014)(China)the University of Calgary’s Canada First Research Excellence Fund(CFREF)program(Canada)for financial support。
文摘This work uses thermal polymerization of urea nitrate,oxyacetic acid and urea as the raw material to prepare ultra-thin porous carbon nitride with carbon defects and C-O band(OA-UN-CN).Density functional theory(DFT)calculations showed OA-UN-CN had narrower band gap,faster electron transport and a new internal construction electric field.Additionally,the prepared OA-UN-CN significantly enhanced photocatalytic activation of peroxymonosulfate(PMS)due to enhanced light absorption performance and faster electron overflow.As the result,the OA-UN-CN/PMS could entirely degrade bisphenol A(BPA)within 30 min,where the photodegradation rate was 81.8 and 7.9 times higher than that of g-C_(3)N_(4)and OA-UN-CN,respectively.Beyond,the OA-UN-CN/PMS could likewise degrade other bisphenol pollutants and sodium lignosulfonate efficiently.We suggested possible photocatalytic degradation pathways accordingly and explored the toxicity of its degradation products.This work provides a new idea on the development of advanced photocatalytic oxidation processes for the treatment of bisphenol pollutants and lignin derivatives,via a metal-free photothermal-catalyst.
基金supported in part by the projects from the National Natural Science Foundation of China(No.51972145)Jinan Science&Technology Bureau,China(No.2021GXRC109)Science and Technology Program of the University of Jinan,China(No.XKY2118).
文摘The photocatalytic activity of catalysts depends on the energy-harvesting ability and the separation or transport of photogenerated carriers.The light absorption capacity of graphitic carbon nitride(g-C_(3)N_(4))-based composites can be enhanced by adjusting the surface plasmon resonance(SPR)of noble metal nanoparticles(e.g.,Cu,Au,and Pd)in the entire visible region.Adjustments can be carried out by varying the nanocomponents of the materials.The SPR of noble metals can enhance the local electromagnetic field and improve interband transition,and resonant energy transfer occurs from plasmonic dipoles to electron-hole pairs via near-field electromagnetic interactions.Thus,noble metals have emerged as relevant nanocomponents for g-C_(3)N_(4) used in CO_(2) photoreduction and water splitting.Herein,recent key advances in noble metals(either in single atom,cluster,or nanoparticle forms)and composite photocatalysts based on inorganic or organic nanocomponent-incorporated g-C_(3)N_(4) nanosheets are systematically discussed,including the applications of these photocatalysts,which exhibit improved photoinduced charge mobility in CO_(2) photoconversion and H2 production.Issues related to the different types of multi-nanocomponent heterostructures(involving Schottky junctions,Z-/S-scheme heterostructures,noble metals,and additional semiconductor nanocomponents)and the adjustment of dimensionality of heterostructures(by incorporating noble metal nanoplates on g-C_(3)N_(4) forming 2D/2D heterostructures)are explored.The current prospects and possible challenges of g-C_(3)N_(4) composite photocatalysts incorporated with noble metals(e.g.,Au,Pt,Pd,and Cu),particularly in water splitting,CO_(2) reduction,pollution degradation,and chemical conversion applications,are summarized.
文摘光催化灭活是公认的控制病原微生物最具前景手段之一。本文以尿素和硫代巴比妥酸为起始原料,通过热聚合反应制备S掺杂g-C_(3)N_(4)(SCN),随后采用光还原法将Ag纳米粒负载于SCN表面获得新颖的可见光响应型Ag/SCN抗菌材料。对所制备纳米材料进行XRD、SEM、TEM、XPS及UV-Vis DRS表征,并深入探讨其在可见光下灭活大肠杆菌(E.coli)的性能和机制。结果表明,Ag纳米粒均匀且牢固地负载在SCN表面,纳米材料表现出显著增强的可见光响应能力。当负载量为6%时,Ag/SCN-6呈现出最佳的光催化灭菌活性,60 min内能够将6.2 lg CFU·mL^(-1)的E.coli全部灭活。自由基捕获实验结果表明,超氧自由基(·O-2)是灭活过程中最主要活性物种,它协同光生空穴(h+)和羟基自由基(·OH)主导了光催化抗菌的进程。
