The rational fabrication of an efficient heterojunction is critical to the enhancement of photocatalytic hydrogen(H_(2)) evolution performance.Herein,a new-fashioned graphitic-carbon nitride(g-C_(3) N_(4)) based isoty...The rational fabrication of an efficient heterojunction is critical to the enhancement of photocatalytic hydrogen(H_(2)) evolution performance.Herein,a new-fashioned graphitic-carbon nitride(g-C_(3) N_(4)) based isotype step-scheme(S-scheme) heterojunction composed of sulfur-doped and sulfur-free active sites is developed by liquid sulfur-mediation of exfoliated g-C_(3) N_(4).Particularly,the liquid sulfur not only contributes to the full contact between sulfur species and exfoliated g-C_(3) N_(4),but also creates sulfur-doping and abundant pores,since self-gas foaming effect of sulfur vapor.Moreover,the S-doped and S-free active sites located in the structural unit of C_(3) N_(4) jointly construct a typical sulfur-doped g-C_(3) N_(4)/g-C_(3) N_(4) isotype step-scheme heterojunction,which endows highly efficient photocatalytic reaction process.Therefore,the optimal sample possesses remarkable photocatalytic H_(2) evolution activity(5548.1 μmol g^(-1) h^(-1)) and robust durability.Most importantly,the investigation will open up a new path for the exploration of other carbon-based isotype S-scheme heterojunctions.展开更多
The rational construction of a high-efficiency stepscheme heterojunctions is an effective strategy to accelerate the photocatalytic H_(2).Unfortunately,the variant energy-level matching between two different semicondu...The rational construction of a high-efficiency stepscheme heterojunctions is an effective strategy to accelerate the photocatalytic H_(2).Unfortunately,the variant energy-level matching between two different semiconductor confers limited the photocatalytic performance.Herein,a newfangled graphitic-carbon nitride(g-C_(3)N_(4))based isotype step-scheme heterojunction,which consists of sulfur-doped and defective active sites in one microstructural unit,is successfully developed by in-situ polymerizing N,N-dimethylformamide(DMF)and urea,accompanied by sulfur(S)powder.Therein,the polymerization between the amino groups of DMF and the amide group of urea endows the formation of rich defects.The propulsive integration of S-dopants contributes to the excellent fluffiness and dispersibility of lamellar g-C_(3)N_(4).Moreover,the developed heterojunction exhibits a significantly enlarged surface area,thus leading to the more exposed catalytically active sites.Most importantly,the simultaneous introduction of S-doping and defects in the units of g-C_(3)N_(4) also results in a significant improvement in the separation,transfer and recombination efficiency of photo-excited electron-hole pairs.Therefore,the resulting isotype step-scheme heterojunction possesses a superior photocatalytic H_(2) evolution activity in comparison with pristine g-C_(3)N_(4).The newly afforded metal-free isotype step-scheme heterojunction in this work will supply a new insight into coupling strategies of heteroatoms doping and defect engineering for various photocatalytic systems.展开更多
Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen.A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to...Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen.A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to significantly boost the photocatalytic activity,but is yet to be realized.Herein,we find that cobalt salt added in the ionothermal synthesis can promote the phase transition of heptazine-based crystalline carbon nitride(CCN)to triazine-based poly(triazine imide)(PTI),rendering the creation of singleatom cobalt coordinated isotype CCN/PTI heterojunction.Co-CCN/PTI exhibits an appreciable apparent quantum yield of 20.88%at 425 nm for photocatalytic hydrogen production with a rate achieving3538μmol h^(-1)g^(-1)(λ>420 nm),which is 4.8 times that of CCN and 27.6 times that of PTI.The high photocatalytic activity is attributed to the Type II isotype highly-crystallized CCN/PTI heterojunction for promoting charge carrier migration,and the single-atom Co sites for accelerating surface oxidation reaction.展开更多
Photocatalytic conversion of CO_(2) to high-value products plays a crucial role in the global pursuit of carbon–neutral economy.Junction photocatalysts,such as the isotype heterojunctions,offer an ideal paradigm to n...Photocatalytic conversion of CO_(2) to high-value products plays a crucial role in the global pursuit of carbon–neutral economy.Junction photocatalysts,such as the isotype heterojunctions,offer an ideal paradigm to navigate the photocatalytic CO_(2) reduction reaction(CRR).Herein,we elucidate the behaviors of isotype heterojunctions toward photocatalytic CRR over a representative photocatalyst,g-C_(3)N_(4).Impressively,the isotype heterojunctions possess a significantly higher efficiency for the spatial separation and transfer of photogenerated carriers than the single components.Along with the intrinsically outstanding stability,the isotype heterojunctions exhibit an exceptional and stable activity toward the CO_(2) photoreduction to CO.More importantly,by combining quantitative in situ technique with the first-principles modeling,we elucidate that the enhanced photoinduced charge dynamics promotes the production of key intermediates and thus the whole reaction kinetics.展开更多
The facile designs and fabrication of noble metal-free electrocatalysts are highly required to achieve multifunctional catalytic activity with excellent stability in Zn-air batteries,fuel cells and water splitting sys...The facile designs and fabrication of noble metal-free electrocatalysts are highly required to achieve multifunctional catalytic activity with excellent stability in Zn-air batteries,fuel cells and water splitting systems.Herein,a heterostructure engineering is applied to construct the high performance Co,Ncontaining carbon-based multifunctional electrocatalysts with the feature of isotype(i.e.n-n type Co_(2)N_(0.67)-BHPC)and anisotype(i.e.p-n type Co_(2)O_(3)-BHPC)heterojunctions for ORR,OER and HER.The nn type Co_(2)N_(0.67)-BHPC,in which biomass(e.g.mushroom)-derived hierarchical porous carbon(BHPC)incorporated with nonstoichiometric active species Co_(2)N_(0.67),is fabricated by using an in situ protective strategy of macrocyclic central Co-N_(4) from CoTPP(5,10,15,20-tetrakis(phenyl)porphyrinato cobalt)precursor through the intermolecularπ-πinteractions between CoTPP and its metal-free analogue H_(2) TPP.Meanwhile,an unprotected strategy of macrocyclic central Co-N_(4) from CoTPP can afford the anisotype Co_(2)O_(3)-BHPC p-n heterojunction.The as-prepared n-n type Co_(2)N_(0.67)-BHPC heterojunction exhibited a higher density of Co-based active sites with outstanding stability and more efficient charge transfer at the isotype heterojunction interface in comparison with p-n type Co_(2)O_(3)-BHPC heterojunction.Consequently,for ORR,Co_(2)N_(0.67)-BHPC exhibits the more positive onset and half-wave potentials of 0.93 and 0.86 V vs.RHE,respectively,superior to those of the commercial 20 wt%Pt/C and most of Cobased catalysts reported so far.To drive a current density of 10 mA cm^(-2),Co_(2)N_(0.67)-BHPC also shows the lower overpotentials of 0.34 and 0.21 V vs.RHE for OER and HER,respectively.Furthermore,the Zn-air battery equipped with Co_(2)N_(0.67)-BHPC displays higher maximum power density(109 mW cm^(-2))and charge-discharge cycle stability.Interestingly,the anisotype heterojunction Co_(2)O_(3)-BHPC as trifunctional electrocatalyst reveals evidently photoelectrochemical enhancement compared with the photosta展开更多
Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly aggressive pathogen that caused SARS in 2003 and 2004.^(1-4) Spike protein (S) on the surface of virus particles mediates the attachment of the viru...Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly aggressive pathogen that caused SARS in 2003 and 2004.^(1-4) Spike protein (S) on the surface of virus particles mediates the attachment of the virus to cell surface receptors and induces the fusion of viral and cellular membranes. According to the epitope analysis and structure of S protein, we used two fragments of S protein S1 (108-488aa) and S2 (723-938aa) expressed in Escherichia coli and immunized Balb/c mice to investigate the immune response to the recombinant proteins in mice.~5展开更多
Graphitic carbon nitride(g-C_(3)N_(4))is viewed as a promising visible-light photocatalyst for industrialization due to its low processing temperature and high chemical stability.However,serious charge recombination c...Graphitic carbon nitride(g-C_(3)N_(4))is viewed as a promising visible-light photocatalyst for industrialization due to its low processing temperature and high chemical stability.However,serious charge recombination caused by incomplete polymerization during direct calcination of nitrogen-rich precursors significantly limits its photocatalytic performances.To boost charge separation,herein,we propose a rational strategy by constructing a crystalline g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) isotype heterostructure through the molten salt method.Theoretical calculation reveals that apparent charge-transfer channels are formed between g-C_(3)N_(4) and S-doped g-C_(3)N_(4) layers in the heterostructure.Owing to high crystallinity for decreasing charge recombination and isotype heterostructure for efficient charge transfer,the as-prepared g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) showed remarkable photocatalytic performances with the hydrogen production rate elevated by up to 12.3 times of its singular components.Another novelty of this work is we investigated for the first time the piezocatalytic activity of crystalline g-C_(3)N_(4) by characterizing its performance for H2O2 generation and KMnO4 reduction.Strikingly,its superior piezocatalytic performance over components can be further improved by NaBH4 treatment,which is uncovered to enhance the asymmetric structure of crystalline g-C_(3)N_(4) by introducing extra cyano groups and removing partial NHx species in its tri-s-triazine layer structure.This work opens up new strategies for the design of highly efficient polymeric photocatalysts and highlights the piezocatalytic studies of g-C_(3)N_(4).展开更多
基金supported by the National Natural Science Foundation of China (Nos.62004143 and 21975084)the Central Government Guided Local Science and Technology Development Special Fund Project (No.2020ZYYD033)+5 种基金the Natural Science Foundation of Hubei Province (No.2021CFB133)the Opening Fund of Key Laboratory of Rare Mineral,Ministry of Natural Resources(No.KLRM-KF 202005)the Opening Fund of Key Laboratory for Green Chemical Process of Ministry of Education of Wuhan Institute of Technology (No.GCP202101)the Open Research Fund of Key Laboratory of Material Chemistry for Energy Conversion and Storage (HUST),Ministry of Education (No.2021JYBKF05)the Innovation Project of Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education (No.LCX2021003)the 12^(th) Graduate Education Innovation Fund of Wuhan Institute of Technology (No.CX2020341)。
文摘The rational fabrication of an efficient heterojunction is critical to the enhancement of photocatalytic hydrogen(H_(2)) evolution performance.Herein,a new-fashioned graphitic-carbon nitride(g-C_(3) N_(4)) based isotype step-scheme(S-scheme) heterojunction composed of sulfur-doped and sulfur-free active sites is developed by liquid sulfur-mediation of exfoliated g-C_(3) N_(4).Particularly,the liquid sulfur not only contributes to the full contact between sulfur species and exfoliated g-C_(3) N_(4),but also creates sulfur-doping and abundant pores,since self-gas foaming effect of sulfur vapor.Moreover,the S-doped and S-free active sites located in the structural unit of C_(3) N_(4) jointly construct a typical sulfur-doped g-C_(3) N_(4)/g-C_(3) N_(4) isotype step-scheme heterojunction,which endows highly efficient photocatalytic reaction process.Therefore,the optimal sample possesses remarkable photocatalytic H_(2) evolution activity(5548.1 μmol g^(-1) h^(-1)) and robust durability.Most importantly,the investigation will open up a new path for the exploration of other carbon-based isotype S-scheme heterojunctions.
基金This work was supported by the National Natural Science Foundation of China(No.62004143)the Central Government Guided Local Science and Technology Development Special Fund Project(No.2020ZYYD033)+4 种基金the Natural Science Foundation of Hubei Province(No.2021CFB133)the Opening Fund of Key Laboratory of Rare Mineral Ministry of Natural Resources(No.KLRM-KF 202005)the Open Research Fund of Key Laboratory of Material Chemistry for Energy Conversion and Storage(HUST),Ministry of Education(No.2021JYBKF05)the Opening Fund of Key Laboratory for Green Chemical Process of Ministry of Education of Wuhan Institute of Technology(No.GCP202101)the Innovation Project of Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education(No.LCX2021003)。
文摘The rational construction of a high-efficiency stepscheme heterojunctions is an effective strategy to accelerate the photocatalytic H_(2).Unfortunately,the variant energy-level matching between two different semiconductor confers limited the photocatalytic performance.Herein,a newfangled graphitic-carbon nitride(g-C_(3)N_(4))based isotype step-scheme heterojunction,which consists of sulfur-doped and defective active sites in one microstructural unit,is successfully developed by in-situ polymerizing N,N-dimethylformamide(DMF)and urea,accompanied by sulfur(S)powder.Therein,the polymerization between the amino groups of DMF and the amide group of urea endows the formation of rich defects.The propulsive integration of S-dopants contributes to the excellent fluffiness and dispersibility of lamellar g-C_(3)N_(4).Moreover,the developed heterojunction exhibits a significantly enlarged surface area,thus leading to the more exposed catalytically active sites.Most importantly,the simultaneous introduction of S-doping and defects in the units of g-C_(3)N_(4) also results in a significant improvement in the separation,transfer and recombination efficiency of photo-excited electron-hole pairs.Therefore,the resulting isotype step-scheme heterojunction possesses a superior photocatalytic H_(2) evolution activity in comparison with pristine g-C_(3)N_(4).The newly afforded metal-free isotype step-scheme heterojunction in this work will supply a new insight into coupling strategies of heteroatoms doping and defect engineering for various photocatalytic systems.
基金supported by the National Key Research and Development Program of China(2018YFB1502003)the National Natural Science Foundation of China(51961165103)supported by the National Program for Support of Top-notch Young Professionals and‘‘The Youth Innovation Team of Shaanxi Universities”。
文摘Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen.A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to significantly boost the photocatalytic activity,but is yet to be realized.Herein,we find that cobalt salt added in the ionothermal synthesis can promote the phase transition of heptazine-based crystalline carbon nitride(CCN)to triazine-based poly(triazine imide)(PTI),rendering the creation of singleatom cobalt coordinated isotype CCN/PTI heterojunction.Co-CCN/PTI exhibits an appreciable apparent quantum yield of 20.88%at 425 nm for photocatalytic hydrogen production with a rate achieving3538μmol h^(-1)g^(-1)(λ>420 nm),which is 4.8 times that of CCN and 27.6 times that of PTI.The high photocatalytic activity is attributed to the Type II isotype highly-crystallized CCN/PTI heterojunction for promoting charge carrier migration,and the single-atom Co sites for accelerating surface oxidation reaction.
基金This work was financially supported in part by the National Natural Science Foundation of China(Grant Nos.12047564,52071041,12074048)the Project for Fundamental and Frontier Research in Chongqing(cstc2020jcyj-msxmX0777 and cstc2020jcyj-msxmX0796)+1 种基金the Fundamental Research Funds for the Central Universities(cqu2018CDHB1A09,106112016CDJZR308808)Open access funding provided by Shanghai Jiao Tong University
文摘Photocatalytic conversion of CO_(2) to high-value products plays a crucial role in the global pursuit of carbon–neutral economy.Junction photocatalysts,such as the isotype heterojunctions,offer an ideal paradigm to navigate the photocatalytic CO_(2) reduction reaction(CRR).Herein,we elucidate the behaviors of isotype heterojunctions toward photocatalytic CRR over a representative photocatalyst,g-C_(3)N_(4).Impressively,the isotype heterojunctions possess a significantly higher efficiency for the spatial separation and transfer of photogenerated carriers than the single components.Along with the intrinsically outstanding stability,the isotype heterojunctions exhibit an exceptional and stable activity toward the CO_(2) photoreduction to CO.More importantly,by combining quantitative in situ technique with the first-principles modeling,we elucidate that the enhanced photoinduced charge dynamics promotes the production of key intermediates and thus the whole reaction kinetics.
基金financially supported by the National Natural Science Foundation of China(21771192)Major Program of Shandong Province Natural Science Foundation(ZR2017ZB0315)+3 种基金Program for Taishan Scholar of Shandong Province(ts201712019)the Fundamental Research Funds for the Central Universities(19CX05001A,18CX02053A)Qingdao Applied Basic Research Project(19-6-2-20-cg)Yankuang Group 2019 Science and Technology Program。
文摘The facile designs and fabrication of noble metal-free electrocatalysts are highly required to achieve multifunctional catalytic activity with excellent stability in Zn-air batteries,fuel cells and water splitting systems.Herein,a heterostructure engineering is applied to construct the high performance Co,Ncontaining carbon-based multifunctional electrocatalysts with the feature of isotype(i.e.n-n type Co_(2)N_(0.67)-BHPC)and anisotype(i.e.p-n type Co_(2)O_(3)-BHPC)heterojunctions for ORR,OER and HER.The nn type Co_(2)N_(0.67)-BHPC,in which biomass(e.g.mushroom)-derived hierarchical porous carbon(BHPC)incorporated with nonstoichiometric active species Co_(2)N_(0.67),is fabricated by using an in situ protective strategy of macrocyclic central Co-N_(4) from CoTPP(5,10,15,20-tetrakis(phenyl)porphyrinato cobalt)precursor through the intermolecularπ-πinteractions between CoTPP and its metal-free analogue H_(2) TPP.Meanwhile,an unprotected strategy of macrocyclic central Co-N_(4) from CoTPP can afford the anisotype Co_(2)O_(3)-BHPC p-n heterojunction.The as-prepared n-n type Co_(2)N_(0.67)-BHPC heterojunction exhibited a higher density of Co-based active sites with outstanding stability and more efficient charge transfer at the isotype heterojunction interface in comparison with p-n type Co_(2)O_(3)-BHPC heterojunction.Consequently,for ORR,Co_(2)N_(0.67)-BHPC exhibits the more positive onset and half-wave potentials of 0.93 and 0.86 V vs.RHE,respectively,superior to those of the commercial 20 wt%Pt/C and most of Cobased catalysts reported so far.To drive a current density of 10 mA cm^(-2),Co_(2)N_(0.67)-BHPC also shows the lower overpotentials of 0.34 and 0.21 V vs.RHE for OER and HER,respectively.Furthermore,the Zn-air battery equipped with Co_(2)N_(0.67)-BHPC displays higher maximum power density(109 mW cm^(-2))and charge-discharge cycle stability.Interestingly,the anisotype heterojunction Co_(2)O_(3)-BHPC as trifunctional electrocatalyst reveals evidently photoelectrochemical enhancement compared with the photosta
文摘Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly aggressive pathogen that caused SARS in 2003 and 2004.^(1-4) Spike protein (S) on the surface of virus particles mediates the attachment of the virus to cell surface receptors and induces the fusion of viral and cellular membranes. According to the epitope analysis and structure of S protein, we used two fragments of S protein S1 (108-488aa) and S2 (723-938aa) expressed in Escherichia coli and immunized Balb/c mice to investigate the immune response to the recombinant proteins in mice.~5
基金supported by the National Natural Science Foundation of China(51902045,51904059)Fundamental Research Funds for the Central Universities(N182503030,N182505036,N2002005)+1 种基金Liao Ning Revitalization Talents Program(XLYC1807123)Young Elite Scientist Sponsorship Program by CAST(YESS)2019-2021QNRC.
文摘Graphitic carbon nitride(g-C_(3)N_(4))is viewed as a promising visible-light photocatalyst for industrialization due to its low processing temperature and high chemical stability.However,serious charge recombination caused by incomplete polymerization during direct calcination of nitrogen-rich precursors significantly limits its photocatalytic performances.To boost charge separation,herein,we propose a rational strategy by constructing a crystalline g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) isotype heterostructure through the molten salt method.Theoretical calculation reveals that apparent charge-transfer channels are formed between g-C_(3)N_(4) and S-doped g-C_(3)N_(4) layers in the heterostructure.Owing to high crystallinity for decreasing charge recombination and isotype heterostructure for efficient charge transfer,the as-prepared g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) showed remarkable photocatalytic performances with the hydrogen production rate elevated by up to 12.3 times of its singular components.Another novelty of this work is we investigated for the first time the piezocatalytic activity of crystalline g-C_(3)N_(4) by characterizing its performance for H2O2 generation and KMnO4 reduction.Strikingly,its superior piezocatalytic performance over components can be further improved by NaBH4 treatment,which is uncovered to enhance the asymmetric structure of crystalline g-C_(3)N_(4) by introducing extra cyano groups and removing partial NHx species in its tri-s-triazine layer structure.This work opens up new strategies for the design of highly efficient polymeric photocatalysts and highlights the piezocatalytic studies of g-C_(3)N_(4).
