S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB...S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)degradation.The effects of two different mixing routes were identified on the MB degradation performance.Particularly,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with Co-S.Furthermore,the degradation parameters,including pH and MOF-AEP dosage,were investigated.Finally,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.展开更多
Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading tetracycline.XRD and TEM results showed that Cu and Mn were successfully co-doped into CeO_...Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading tetracycline.XRD and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer process.Notably,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.展开更多
Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),...Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),x=1.0,2.0,3.0,4.0)was synthesized via solid-phase reaction of sodium citrate(NaCA)and pure CN powder in the Teflon-sealed autoclave under air conditions at 180℃.Surface area of Na/O-CN_(3.0) is measured to be 18.8 m^(2)/g,increasing by 60.7%compared to that of pure CN(11.7 m^(2)/g).Bandgap energy of Na/O-CN_(3.0) is determined to be 2.68 eV,marginally lower than that of pure CN(2.70 eV),thereby enhancing its capacity for sunlight absorption.Meanwhile,the incorporation of Na and O atoms into Na/O-CN_(x) is found to effectively reduce recombination rates of photogenerated electron-hole pairs.As a result,Na/O-CN_(x) samples exhibit markedly enhanced photocatalytic hydrogen evolution activity under visible light irradiation.Notably,the optimal Na/O-CN_(3.0) sample achieves a photocatalytic hydrogen production rate of 103.2μmol·g^(–1)·h^(–1),which is 8.2 times greater than that of pure CN(11.2μmol·g^(–1)·h^(–1)).Furthermore,a series of Na/O-CN_(x)-yO_(2)(y=0,20%,40%,60%,80%,100%)samples were prepared by modulating the oxygen content within reaction atmosphere.The catalytic performance evaluations reveal that the incorporation of both Na and O atoms in Na/O-CN_(3.0) enhances photocatalytic activity.This study also introduces novel methodologies for synthesis of metal atom-doped CN materials at lower temperature,highlighting the synergistic effect of Na and O atoms in photocatalytic hydrogen production of Na/O-CN_(x) samples.展开更多
For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of e...For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).展开更多
Nitrogen-phosphorus co-doped carbon dots(N,P-CDs)were synthesized via a one-step hydrothermal method using p-phenylene diisocyanate,ethylenediamine,and concentrated phosphoric acid as raw materials.The morphology,stru...Nitrogen-phosphorus co-doped carbon dots(N,P-CDs)were synthesized via a one-step hydrothermal method using p-phenylene diisocyanate,ethylenediamine,and concentrated phosphoric acid as raw materials.The morphology,structure,and optical properties of the N,P-CDs were characterized in detail.The N,P-CDs exhibit excellent water solubility,with optimal excitation and emission wavelengths of 392 nm and 520 nm,respectively.A novel fluorescence method for detection of curcumin was developed,demonstrating a linear range of 3.50-242.24μmol/L and a detection limit of 0.086μmol/L.When applied to the detection of curcumin in real water samples and chili powder seasoning,the method achieved recovery between 94.48%and 105.82%,and with the relative standard deviations(RSDs)ranging from 0.17%to 0.62%.These results highlight that the constructed fluorescence analysis method based on the N,P-CDs has the potential for the accurate and reliable detection of curcumin in real-world samples.展开更多
Flexible energy storage devices have been paid much attention and adapts to apply in various fields.Benefiting from the active sites of boron(B)and phosphorus(P)doping materials,co-doped carbon materials are widely us...Flexible energy storage devices have been paid much attention and adapts to apply in various fields.Benefiting from the active sites of boron(B)and phosphorus(P)doping materials,co-doped carbon materials are widely used in energy storage devices for the enhanced electrochemical performance.Herein,B and P co-doped flexible carbon nanofibers with nitrogen-rich(B-P/NC)are investigated with electro-spinning for sodium-ion battery.The flexible of binderless B-P/NC with annealing of 600℃(B-P/NC-600)exhibits the remarkable performance for the robust capacity of 200 mAh/g at 0.1 A/g after 500 cycles and a durable reversible capacity of 160 m Ah/g even at 1 A/g after 12,000 cycles,exhibiting the equally commendable stability of flexible B-P/NC-600.In addition,B-P/NC-600 delivers the reversible capacity of265 m Ah/g with the test temperature of 60℃.More importantly,the flexible B-P/NC-600 is fabricated as anode for the whole battery,delivering the capacity of 90 m Ah/g at 1 A/g after 200 cycles.Meanwhile,theoretical calculation further verified that boron and phosphorus co-doping can improve the adsorption capacity of nitrogen carbon materials.The favorable performance of flexible B-P/NC-600 can be ascribed to the nitrogen-rich carbon nanofibers with three-dimensional network matrix for the more active site of boron and phosphorus co-doping.Our work paves the way for the improvement of flexible anodes and wide-operating temperature of sodium-ion batteries by doping approach of much heteroatom.展开更多
Ce^(3+),due to its broadband emission,has the potential to serve as a donor ion for energy transfer to achieve the possible efficient tunable multi-emission in materials.However,current related research primarily focu...Ce^(3+),due to its broadband emission,has the potential to serve as a donor ion for energy transfer to achieve the possible efficient tunable multi-emission in materials.However,current related research primarily focuses on photoluminescent(PL)phosphors,while studies on achieving tunable long persistent luminescence(LPL),particularly in glass materials,are insufficient.In this work,Ce-Tb codoped boroaluminate glass was synthesized using a high-temperature melting method under a reducing atmosphere.Under the influence of oxygen vacancy traps induced during the reduction of Ce^(4+)to Ce^(3+),glass samples exhibit an obvious LPL with a broadband center wavelength at 420 nm and a narrowband center wavelength at 547 nm,which correspond well to Ce^(3+)ions'd-f transitions and Tb^(3+)ions'f-f transitions,respectively.A reasonable Ce^(3+)doping amount achieves the optimal trap depth and concentration to enhance LPL intensity and duration.Additionally,it improves the PL intensity of Tb^(3+)by enhancing the energy transfer from Ce^(3+)to Tb^(3+),thereby enabling the glass to exhibit variable LPL colo rs ranging from blue to cyan.Finally,based on the PL and LPL characteristics of the samples,a dynamic encryption anticounterfeiting application is described.展开更多
Monolithic catalysts with excellent O_(3)catalytic decomposition performance were prepared by in situ loading of Co-doped KMn_(8)O_(16)on the surface of nickel foam.The triple-layer structure with Co-doped KMn_(8)O_(1...Monolithic catalysts with excellent O_(3)catalytic decomposition performance were prepared by in situ loading of Co-doped KMn_(8)O_(16)on the surface of nickel foam.The triple-layer structure with Co-doped KMn_(8)O_(16)/Ni6MnO_(8)/Ni foam was grown spontaneously on the surface of nickel foam by tuning the molar ratio of KMnO_(4)to Co(NO_(3))_(2)·6H_(2)O precursors.Importantly,the formed Ni6MnO_(8)structure between KMn_(8)O_(16)and nickel foam during in situ synthesis process effectively protected nickel foam from further etching,which significantly enhanced the reaction stability of catalyst.The optimum amount of Co doping in KMn_(8)O_(16)was available when the molar ratio of Mn to Co species in the precursor solution was 2:1.And the Mn2Co1 catalyst had abundant oxygen vacancies and excellent hydrophobicity,thus creating outstanding O_(3)decomposition activity.The O_(3)conversion under dry conditions and relative humidity of 65%,90%over a period of 5 hr was 100%,94%and 80%with the space velocity of 28,000 hr^(−1),respectively.The in situ constructed Co-doped KMn_(8)O_(16)/Ni foam catalyst showed the advantages of low price and gradual applicability of the preparation process,which provided an opportunity for the design of monolithic catalyst for O_(3)catalytic decomposition.展开更多
Aqueous zinc-based energy storage devices(ZESDs)have garnered considerable interest because of their high specific capacity,abundant zinc reserves,excellent safety,and environmental friendliness.In recent years,variou...Aqueous zinc-based energy storage devices(ZESDs)have garnered considerable interest because of their high specific capacity,abundant zinc reserves,excellent safety,and environmental friendliness.In recent years,various types of boron,nitrogen co-doped carbon(BNC)materials have been developed to improve electrochemical performance of ZESDs.To promote the advancement of these technologies,we herein give a comprehensive review of the progress in BNC materials for ZESDs.The different synthetic methods employed in the preparation of BNC materials,including direct carbonization,template method,chemical vapor deposition,hydrothermal method,etc.,are summarized.These methods play a vital role in tailoring the structure,composition,and properties of BNC materials to optimize their performance in energy storage applications.Furthermore,some key achievements of BNC materials in zinc-air batteries and zinc-ion hybrid supercapacitors are elaborated.Lastly,future challenges and development directions of BNC materials in ZESDs are prospected.This comprehensive review could serve as a valuable resource in the energy storage field,providing insights into the potential of BNC materials in zinc-based energy storage technologies.展开更多
Harnessing the redox potential of biochar to activate airborne O_(2)for contaminant removal is challenging.In this study,ferrihydrite(Fh)modified the boron(B),nitrogen(N)co-doped biochars(BCs)composites(Fh/B(n)NC)were...Harnessing the redox potential of biochar to activate airborne O_(2)for contaminant removal is challenging.In this study,ferrihydrite(Fh)modified the boron(B),nitrogen(N)co-doped biochars(BCs)composites(Fh/B(n)NC)were developed for enhancing the degradation of a model pollutant,tetracycline(TC),merely by airborne O_(2).Fh/B(3)NC showed excellent O_(2)activation activity for efficient TC degradation with a apparent TC degradation rate of 5.54,6.88,and 22.15 times that of B(3)NC,Fh,and raw BCs,respectively,where 1O_(2)and H_(2)O_(2)were identified as the dominant ROS for TC degradation.The B incorporation into the carbon lattice of Fh/B(3)NC promoted the generation of electron donors,sp2 C and the reductive B species,hence boosting Fe(III)reduction and 1O_(2)generation.O_(2)adsorption was enhanced due to the positively charged adsorption sites(C-B+and N-C+).And 1O_(2)was generated via Fe(II)catalyzed low-efficient successive one-electron transfer(O_(2)→O_(2)·−→1O_(2),H_(2)O_(2)),as well as biochar catalyzed high-efficient two-electron transfer(O_(2)→H_(2)O_(2)→1O_(2))that does not involve.O_(2)−as the intermediate.Moreover,Fh/B,N co-doped biochar showed a wide pH range,remarkable anti-interference capabilities,and effective detoxification.These findings shed new light on the development of environmentally benign BCs materials capable of degradading organic pollutants.展开更多
We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method,and carefully investigated the luminescent properties and the spectral modulation of Tb/Eucodoped borosilicate...We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method,and carefully investigated the luminescent properties and the spectral modulation of Tb/Eucodoped borosilicate glasses under UV(200-400 nm)excitation.The results show that the prepared samples have the characteristics of broadband response,excellent transparency and tunable luminescence.By adjusting the excitation wavelength,the emissions of Tb^(3+),Eu^(2+)and Eu^(3+)ions are observed,which exhibit yellow-green,blue,red color and multi-color even white emissions,respectively.Moreover,the energy transfer between Tb^(3+)and Eu^(3+)ions in the codoped glasses is confirmed.Tb^(3+)absorbs a large number of solar-blind light,transfers to Eu^(3+)and results in intense visible emission in a wide waveband range.This makes the Tb/Eu co-doped glass a desirable candidate for solar-blind light detections.The photodetection system was built and shows a strong and stable response to the UV light of 210-400 nm.Due to broad detection range,high sensitivity and stability,our results offer strong implications for the development of photodetection device for diverse applications.展开更多
K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concent...K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concentrations of 50 and 100μg/mL.After 24 h of incubation treatment,cell viability decreased to(36.8±6.5)% and(33.4±6.4)%at 50 and 100μg/mL,respectively.With extended exposure to 48 h,cell viability was(45.2±2.3)%and(32.3±2.8)%at the same concentrations.Phase-contrast microscopy revealed characteristic morphological changes including cell shrinkage and membrane blebbing formation,indicative of cell death.These findings demonstrate the potential of KNMOH nanoflowers as a cytotoxic agent for cervical cancer applications and provide a foundation for further mechanistic studies.展开更多
Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by ...Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.展开更多
Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable...Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.展开更多
The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ...The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.展开更多
Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption metho...Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption method is the most effective and convenient method. The adsorption amount of traditional activated carbon is limited, so it needs to be modified to improve the adsorption rate. This experiment determined a reasonable modification method, and the calcination method was selected for the modification. This paper mainly compares the surface morphological characteristics of activated carbon before and after modification. The modified X-ray diffraction peak is increased and the infrared ray absorption peak increased, and the results show that the surface of the modified activated carbon is more rough than that of the modified activated carbon, the functional groups are increased, and the sulfur and nitrogen are doped on the activated carbon. Therefore, the modified activated carbon has a high removal rate and the best performance under acidic conditions.展开更多
Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3...Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3)N_(4)(N,S-g-C_(3)N_(4))is elaborately designed on the basis of theoretical predictions of first-principle density functional theory(DFT).The calculated Gibbs free energy of adsorbed hydrogen(ΔGH∗)for N,S-g-C_(3)N_(4) at the N-doping active sites is extremely close to zero(0.01 eV).Inspired by the theoretical predictions,the N,S-g-C_(3)N_(4) is successfully fabricated through ammonia-rich pyrolysis synthesis strategy,in which ammonia is in-situ obtained by pyrolyzing melamine.Subsequent characterizations indicate that the N,S-g-C_(3)N_(4) possesses high specific surface area,outstanding light utilization,good hydrophilicity,and efficient carrier transfer efficiency.Consequently,the N,S-g-C_(3)N_(4) displays an extremely high H2 evolution rate of 8269.9μmol g−1 h−1,achieves an apparent quantum efficiency(AQE)of 3.24%,and also possesses outsatnding durability.Theoretical calculations further demonstrate that N and S dopants can not only introduce doping energy level to reduce the band gap,but also induce charge redistribution to facilitate hydrogen adsorption,thus promoting the photocatalytic HER process.Moreover,femtosecond transient absorption(fs-TA)spectroscopy further corroborates the efficient photogenerated carrier transport of N,S-g-C_(3)N_(4).This research highlights a promising and reliable strategy to achieve superior photocatalytic activity,and exhibits significant guidance for precise designing high-efficiency photocatalysts.展开更多
This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A compar...This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A comparative exploration of TEA gas sensing characterization for different Co_(3)O_(4)-based sensors is conducted systematically.The result shows that the sensor based on the NiZn–Co_(3)O_(4)HCSS displays the highest sensing response of 42.5 at a working temperature of 180°C.In particular,the Ni Zn–Co_(3)O_(4)HCSS device possesses a fast responserecovery speed,excellent anti-humidity and outstanding long-term stability of up to 40 days to TEA gas.The improved TEA gas sensing property can be attributed to the intriguing hierarchical core–shell architecture and abundant oxygen vacancy induced by NiZn co-doping.Moreover,to study the sensing mechanism in detail,the adsorption behavior and charge transfer phenomenon between OV–NiZn–Co_(3)O_(4)(110)and TEA molecule is carried out by the density functional theory(DFT).This work demonstrates an outstanding performance of Ni and Zn co-doped hierarchical core–shell Co_(3)O_(4)in TEA detection by combining theoretical and experimental investigations into mechanisms for optimized TEA gas molecule sensing.展开更多
F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confi...F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confirm that this method effectively promotes the growth of the highly active anatase(001)facets and enhances visible and infrared light absorption while inducing oxygen vacancies.Under optimal conditions,the hydrogen evolution reaches 20.57μmol after 10 h of ultraviolet-visible(UV-Vis)light irradiation,exceeding the commercial TiO_(2)nanoparticles Degussa P25 by more than 10 times.These findings highlight the potential of F-B co-doped TiO_(2)nanosheets for efficient photocatalysis.展开更多
The nitrogen and fluorine co doped TiO 2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetra butyl titanate with ammonium fluoride. Nitrogen and fluorine co doping causes the abso...The nitrogen and fluorine co doped TiO 2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetra butyl titanate with ammonium fluoride. Nitrogen and fluorine co doping causes the absorption edge of TiO 2 to shift to a lower energy region. The photocatalytic activity of co doped TiO 2 with anatase phases was found to be 2 4 times higher than that of the commercial TiO 2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation. The co doped TiO 2 powders only contain anatase phases even at 1000℃. Apparently, ammonium fluoride added retarded phase transformation of the TiO 2 powders from anatase to rutile. The substitutional fluorine and interstitial nitrogen atoms in co doped TiO 2 polycrystalline powder were responsible for the vis light response and caused the absorption edge of TiO 2 to shift to a lower energy region.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51602018 and 51902018)the Natural Science Foundation of Beijing Municipality(No.2154052)+3 种基金the China Postdoctoral Science Foundation(No.2014M560044)the Fundamental Research Funds for the Central Universities(No.FRF-MP-20-22)USTB Research Center for International People-to-people Exchange in Science,Technology and Civilization(No.2022KFYB007)Education and Teaching Reform Foundation at University of Science and Technology Beijing(Nos.2023JGC027,KC2022QYW06,and KC2022TS09)。
文摘S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)degradation.The effects of two different mixing routes were identified on the MB degradation performance.Particularly,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with Co-S.Furthermore,the degradation parameters,including pH and MOF-AEP dosage,were investigated.Finally,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.
基金Funded by the Scientific Research Fund of Wuhan Institute of Technology(No.K2023055)the Key Research and Development Project of Hubei Province(No.2020BCA075)the Shccig-Qinling Program(No.2022QL-XM-ZhuLi-HG-006)。
文摘Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading tetracycline.XRD and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer process.Notably,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.
基金National Natural Science Foundation of China(21806023)Natural Science Foundation of Hunan Province(2021JJ40199)+2 种基金Education Department Foundation of Hunan Province(20C0813)Hunan University of Science and Technology Fundamental Research FundsPostgraduate Scientific Research Innovation Project of Hunan Province(CX20240877)。
文摘Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),x=1.0,2.0,3.0,4.0)was synthesized via solid-phase reaction of sodium citrate(NaCA)and pure CN powder in the Teflon-sealed autoclave under air conditions at 180℃.Surface area of Na/O-CN_(3.0) is measured to be 18.8 m^(2)/g,increasing by 60.7%compared to that of pure CN(11.7 m^(2)/g).Bandgap energy of Na/O-CN_(3.0) is determined to be 2.68 eV,marginally lower than that of pure CN(2.70 eV),thereby enhancing its capacity for sunlight absorption.Meanwhile,the incorporation of Na and O atoms into Na/O-CN_(x) is found to effectively reduce recombination rates of photogenerated electron-hole pairs.As a result,Na/O-CN_(x) samples exhibit markedly enhanced photocatalytic hydrogen evolution activity under visible light irradiation.Notably,the optimal Na/O-CN_(3.0) sample achieves a photocatalytic hydrogen production rate of 103.2μmol·g^(–1)·h^(–1),which is 8.2 times greater than that of pure CN(11.2μmol·g^(–1)·h^(–1)).Furthermore,a series of Na/O-CN_(x)-yO_(2)(y=0,20%,40%,60%,80%,100%)samples were prepared by modulating the oxygen content within reaction atmosphere.The catalytic performance evaluations reveal that the incorporation of both Na and O atoms in Na/O-CN_(3.0) enhances photocatalytic activity.This study also introduces novel methodologies for synthesis of metal atom-doped CN materials at lower temperature,highlighting the synergistic effect of Na and O atoms in photocatalytic hydrogen production of Na/O-CN_(x) samples.
基金financial support from projects funded by the National Natural Science Foundation of China(52172038,22179017)the National Key Research and Development Program of China(2022YFB4101600,2022YFB4101601)。
文摘For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).
基金National Natural Science Foundation of China(No.22274090)The Basic Research Project of Shanxi Province(No.202203021221026)+1 种基金Shanxi Province Patent Conversion Project(No.202306012)Shanxi Provincial Key Laboratory of Classical Prescription Strengthening Yang(No.202104010910011)。
文摘Nitrogen-phosphorus co-doped carbon dots(N,P-CDs)were synthesized via a one-step hydrothermal method using p-phenylene diisocyanate,ethylenediamine,and concentrated phosphoric acid as raw materials.The morphology,structure,and optical properties of the N,P-CDs were characterized in detail.The N,P-CDs exhibit excellent water solubility,with optimal excitation and emission wavelengths of 392 nm and 520 nm,respectively.A novel fluorescence method for detection of curcumin was developed,demonstrating a linear range of 3.50-242.24μmol/L and a detection limit of 0.086μmol/L.When applied to the detection of curcumin in real water samples and chili powder seasoning,the method achieved recovery between 94.48%and 105.82%,and with the relative standard deviations(RSDs)ranging from 0.17%to 0.62%.These results highlight that the constructed fluorescence analysis method based on the N,P-CDs has the potential for the accurate and reliable detection of curcumin in real-world samples.
基金supported by Natural Science Foundation of China(No.6230031623)the Natural Science Foundation of Hunan Province(No.2024JJ5127)+2 种基金the Education Department of Hunan Province(No.22B0580)the Scientific Research and Innovation Foundation of Hunan University of Technology(No.CX2317)the Innovation and Entrepreneurship Training Project for College Students(No.S202311535061)。
文摘Flexible energy storage devices have been paid much attention and adapts to apply in various fields.Benefiting from the active sites of boron(B)and phosphorus(P)doping materials,co-doped carbon materials are widely used in energy storage devices for the enhanced electrochemical performance.Herein,B and P co-doped flexible carbon nanofibers with nitrogen-rich(B-P/NC)are investigated with electro-spinning for sodium-ion battery.The flexible of binderless B-P/NC with annealing of 600℃(B-P/NC-600)exhibits the remarkable performance for the robust capacity of 200 mAh/g at 0.1 A/g after 500 cycles and a durable reversible capacity of 160 m Ah/g even at 1 A/g after 12,000 cycles,exhibiting the equally commendable stability of flexible B-P/NC-600.In addition,B-P/NC-600 delivers the reversible capacity of265 m Ah/g with the test temperature of 60℃.More importantly,the flexible B-P/NC-600 is fabricated as anode for the whole battery,delivering the capacity of 90 m Ah/g at 1 A/g after 200 cycles.Meanwhile,theoretical calculation further verified that boron and phosphorus co-doping can improve the adsorption capacity of nitrogen carbon materials.The favorable performance of flexible B-P/NC-600 can be ascribed to the nitrogen-rich carbon nanofibers with three-dimensional network matrix for the more active site of boron and phosphorus co-doping.Our work paves the way for the improvement of flexible anodes and wide-operating temperature of sodium-ion batteries by doping approach of much heteroatom.
基金Project supported by the Department of Science and Technology of Zhejiang Province,China(2024C01192)。
文摘Ce^(3+),due to its broadband emission,has the potential to serve as a donor ion for energy transfer to achieve the possible efficient tunable multi-emission in materials.However,current related research primarily focuses on photoluminescent(PL)phosphors,while studies on achieving tunable long persistent luminescence(LPL),particularly in glass materials,are insufficient.In this work,Ce-Tb codoped boroaluminate glass was synthesized using a high-temperature melting method under a reducing atmosphere.Under the influence of oxygen vacancy traps induced during the reduction of Ce^(4+)to Ce^(3+),glass samples exhibit an obvious LPL with a broadband center wavelength at 420 nm and a narrowband center wavelength at 547 nm,which correspond well to Ce^(3+)ions'd-f transitions and Tb^(3+)ions'f-f transitions,respectively.A reasonable Ce^(3+)doping amount achieves the optimal trap depth and concentration to enhance LPL intensity and duration.Additionally,it improves the PL intensity of Tb^(3+)by enhancing the energy transfer from Ce^(3+)to Tb^(3+),thereby enabling the glass to exhibit variable LPL colo rs ranging from blue to cyan.Finally,based on the PL and LPL characteristics of the samples,a dynamic encryption anticounterfeiting application is described.
基金supported by the National Natural Science Foundation of China (Nos.21876019 and 22276022)the National Key Research and Development Program of China (No.2019YFC1903903).
文摘Monolithic catalysts with excellent O_(3)catalytic decomposition performance were prepared by in situ loading of Co-doped KMn_(8)O_(16)on the surface of nickel foam.The triple-layer structure with Co-doped KMn_(8)O_(16)/Ni6MnO_(8)/Ni foam was grown spontaneously on the surface of nickel foam by tuning the molar ratio of KMnO_(4)to Co(NO_(3))_(2)·6H_(2)O precursors.Importantly,the formed Ni6MnO_(8)structure between KMn_(8)O_(16)and nickel foam during in situ synthesis process effectively protected nickel foam from further etching,which significantly enhanced the reaction stability of catalyst.The optimum amount of Co doping in KMn_(8)O_(16)was available when the molar ratio of Mn to Co species in the precursor solution was 2:1.And the Mn2Co1 catalyst had abundant oxygen vacancies and excellent hydrophobicity,thus creating outstanding O_(3)decomposition activity.The O_(3)conversion under dry conditions and relative humidity of 65%,90%over a period of 5 hr was 100%,94%and 80%with the space velocity of 28,000 hr^(−1),respectively.The in situ constructed Co-doped KMn_(8)O_(16)/Ni foam catalyst showed the advantages of low price and gradual applicability of the preparation process,which provided an opportunity for the design of monolithic catalyst for O_(3)catalytic decomposition.
基金financially supported by the National Natural Science Foundation of China(No.22302177)the Public Technology Application Project of Jinhua City(No.2022–4-067)the Self Designed Scientific Research of Zhejiang Normal University(No.2021ZS0604)。
文摘Aqueous zinc-based energy storage devices(ZESDs)have garnered considerable interest because of their high specific capacity,abundant zinc reserves,excellent safety,and environmental friendliness.In recent years,various types of boron,nitrogen co-doped carbon(BNC)materials have been developed to improve electrochemical performance of ZESDs.To promote the advancement of these technologies,we herein give a comprehensive review of the progress in BNC materials for ZESDs.The different synthetic methods employed in the preparation of BNC materials,including direct carbonization,template method,chemical vapor deposition,hydrothermal method,etc.,are summarized.These methods play a vital role in tailoring the structure,composition,and properties of BNC materials to optimize their performance in energy storage applications.Furthermore,some key achievements of BNC materials in zinc-air batteries and zinc-ion hybrid supercapacitors are elaborated.Lastly,future challenges and development directions of BNC materials in ZESDs are prospected.This comprehensive review could serve as a valuable resource in the energy storage field,providing insights into the potential of BNC materials in zinc-based energy storage technologies.
基金supported by the National Natural Science Foundation of China(No.U21A20293).
文摘Harnessing the redox potential of biochar to activate airborne O_(2)for contaminant removal is challenging.In this study,ferrihydrite(Fh)modified the boron(B),nitrogen(N)co-doped biochars(BCs)composites(Fh/B(n)NC)were developed for enhancing the degradation of a model pollutant,tetracycline(TC),merely by airborne O_(2).Fh/B(3)NC showed excellent O_(2)activation activity for efficient TC degradation with a apparent TC degradation rate of 5.54,6.88,and 22.15 times that of B(3)NC,Fh,and raw BCs,respectively,where 1O_(2)and H_(2)O_(2)were identified as the dominant ROS for TC degradation.The B incorporation into the carbon lattice of Fh/B(3)NC promoted the generation of electron donors,sp2 C and the reductive B species,hence boosting Fe(III)reduction and 1O_(2)generation.O_(2)adsorption was enhanced due to the positively charged adsorption sites(C-B+and N-C+).And 1O_(2)was generated via Fe(II)catalyzed low-efficient successive one-electron transfer(O_(2)→O_(2)·−→1O_(2),H_(2)O_(2)),as well as biochar catalyzed high-efficient two-electron transfer(O_(2)→H_(2)O_(2)→1O_(2))that does not involve.O_(2)−as the intermediate.Moreover,Fh/B,N co-doped biochar showed a wide pH range,remarkable anti-interference capabilities,and effective detoxification.These findings shed new light on the development of environmentally benign BCs materials capable of degradading organic pollutants.
基金Project supported by the Significant Science and Technology Projects of LongMen Laboratory in Henan Province(231100220100,231100221100)the Key Research and Development Program of Henan province(231111222200)+2 种基金the College Students Innovations Special Project(202410482008)the National Natural Science Foundation of China(62275105,12104163)Basic Scientific Research Operating Expenses of Henan Academy of Sciences(240607004)。
文摘We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method,and carefully investigated the luminescent properties and the spectral modulation of Tb/Eucodoped borosilicate glasses under UV(200-400 nm)excitation.The results show that the prepared samples have the characteristics of broadband response,excellent transparency and tunable luminescence.By adjusting the excitation wavelength,the emissions of Tb^(3+),Eu^(2+)and Eu^(3+)ions are observed,which exhibit yellow-green,blue,red color and multi-color even white emissions,respectively.Moreover,the energy transfer between Tb^(3+)and Eu^(3+)ions in the codoped glasses is confirmed.Tb^(3+)absorbs a large number of solar-blind light,transfers to Eu^(3+)and results in intense visible emission in a wide waveband range.This makes the Tb/Eu co-doped glass a desirable candidate for solar-blind light detections.The photodetection system was built and shows a strong and stable response to the UV light of 210-400 nm.Due to broad detection range,high sensitivity and stability,our results offer strong implications for the development of photodetection device for diverse applications.
文摘K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concentrations of 50 and 100μg/mL.After 24 h of incubation treatment,cell viability decreased to(36.8±6.5)% and(33.4±6.4)%at 50 and 100μg/mL,respectively.With extended exposure to 48 h,cell viability was(45.2±2.3)%and(32.3±2.8)%at the same concentrations.Phase-contrast microscopy revealed characteristic morphological changes including cell shrinkage and membrane blebbing formation,indicative of cell death.These findings demonstrate the potential of KNMOH nanoflowers as a cytotoxic agent for cervical cancer applications and provide a foundation for further mechanistic studies.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22076063,22076098,and 21477047)the Natural Science Foundation of Shandong Province(No.ZR2020MB033)+1 种基金the Key Laboratory of Photochemical Conversion and Optoelectronic Materials,TIPC,CAS(No.PCOM202106)the program for Taishan Scholars of Shandong Province,and the Science and Technology Programof the University of Jinan(No.XKY2111).
文摘Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.
基金financially supported by the National Natural Science Foundation of China(12175089,12205127,52220105010)the Key Research and Development Program of Yunnan Province(202103AF140006)+3 种基金the Applied Basic Research Programs of Yunnan Provincial Science and Technology Department(202001AW070004,202301AS070051,202301AU070064)Yunnan Industrial Innovative Talents Program for“Xingdian Talent Support Plan”(KKXY202252001)Yunnan Program for Introducing Foreign Talents(202305AO350042)Yunnan Major Scientific and Technological Projects(202202AG050003).
文摘Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.
基金supported by the Science Technology Talents Lifting Project of Hunan Province(No.2022TJ-N16)the Natural Science Foundation of Hunan Province(Nos.2024JJ4022,2023JJ30277,2025JJ60382)+3 种基金the China Postdoctoral Fellowship Program(GZC20233205)the Scientifc Research Fund of Hunan Provincial Education Department,China(No.24B0270)the National Natural Science Foundation of China(No.32201646)the Key Project of Jiangxi Provincial Research and Development Program(No.20243BBI91001).
文摘The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.
文摘Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption method is the most effective and convenient method. The adsorption amount of traditional activated carbon is limited, so it needs to be modified to improve the adsorption rate. This experiment determined a reasonable modification method, and the calcination method was selected for the modification. This paper mainly compares the surface morphological characteristics of activated carbon before and after modification. The modified X-ray diffraction peak is increased and the infrared ray absorption peak increased, and the results show that the surface of the modified activated carbon is more rough than that of the modified activated carbon, the functional groups are increased, and the sulfur and nitrogen are doped on the activated carbon. Therefore, the modified activated carbon has a high removal rate and the best performance under acidic conditions.
基金supported by the National Natural Science Foun-dation of China(No.62004143)the Key R&D Program of Hubei Province(No.2022BAA084)the Natural Science Foundation of Hubei Province(No.2021CFB133).
文摘Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3)N_(4)(N,S-g-C_(3)N_(4))is elaborately designed on the basis of theoretical predictions of first-principle density functional theory(DFT).The calculated Gibbs free energy of adsorbed hydrogen(ΔGH∗)for N,S-g-C_(3)N_(4) at the N-doping active sites is extremely close to zero(0.01 eV).Inspired by the theoretical predictions,the N,S-g-C_(3)N_(4) is successfully fabricated through ammonia-rich pyrolysis synthesis strategy,in which ammonia is in-situ obtained by pyrolyzing melamine.Subsequent characterizations indicate that the N,S-g-C_(3)N_(4) possesses high specific surface area,outstanding light utilization,good hydrophilicity,and efficient carrier transfer efficiency.Consequently,the N,S-g-C_(3)N_(4) displays an extremely high H2 evolution rate of 8269.9μmol g−1 h−1,achieves an apparent quantum efficiency(AQE)of 3.24%,and also possesses outsatnding durability.Theoretical calculations further demonstrate that N and S dopants can not only introduce doping energy level to reduce the band gap,but also induce charge redistribution to facilitate hydrogen adsorption,thus promoting the photocatalytic HER process.Moreover,femtosecond transient absorption(fs-TA)spectroscopy further corroborates the efficient photogenerated carrier transport of N,S-g-C_(3)N_(4).This research highlights a promising and reliable strategy to achieve superior photocatalytic activity,and exhibits significant guidance for precise designing high-efficiency photocatalysts.
基金financially supported by the Doctoral Funding projects from Heze University(No.XY22BS07)
文摘This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A comparative exploration of TEA gas sensing characterization for different Co_(3)O_(4)-based sensors is conducted systematically.The result shows that the sensor based on the NiZn–Co_(3)O_(4)HCSS displays the highest sensing response of 42.5 at a working temperature of 180°C.In particular,the Ni Zn–Co_(3)O_(4)HCSS device possesses a fast responserecovery speed,excellent anti-humidity and outstanding long-term stability of up to 40 days to TEA gas.The improved TEA gas sensing property can be attributed to the intriguing hierarchical core–shell architecture and abundant oxygen vacancy induced by NiZn co-doping.Moreover,to study the sensing mechanism in detail,the adsorption behavior and charge transfer phenomenon between OV–NiZn–Co_(3)O_(4)(110)and TEA molecule is carried out by the density functional theory(DFT).This work demonstrates an outstanding performance of Ni and Zn co-doped hierarchical core–shell Co_(3)O_(4)in TEA detection by combining theoretical and experimental investigations into mechanisms for optimized TEA gas molecule sensing.
基金National Natural Science Foundation of China(No.81861138040)。
文摘F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confirm that this method effectively promotes the growth of the highly active anatase(001)facets and enhances visible and infrared light absorption while inducing oxygen vacancies.Under optimal conditions,the hydrogen evolution reaches 20.57μmol after 10 h of ultraviolet-visible(UV-Vis)light irradiation,exceeding the commercial TiO_(2)nanoparticles Degussa P25 by more than 10 times.These findings highlight the potential of F-B co-doped TiO_(2)nanosheets for efficient photocatalysis.
文摘The nitrogen and fluorine co doped TiO 2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetra butyl titanate with ammonium fluoride. Nitrogen and fluorine co doping causes the absorption edge of TiO 2 to shift to a lower energy region. The photocatalytic activity of co doped TiO 2 with anatase phases was found to be 2 4 times higher than that of the commercial TiO 2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation. The co doped TiO 2 powders only contain anatase phases even at 1000℃. Apparently, ammonium fluoride added retarded phase transformation of the TiO 2 powders from anatase to rutile. The substitutional fluorine and interstitial nitrogen atoms in co doped TiO 2 polycrystalline powder were responsible for the vis light response and caused the absorption edge of TiO 2 to shift to a lower energy region.