Photoanode of ZnO branched nanowires, BNW, doped with nitrogen was fabricated to be used in photochemical cell for hydrogen generation from water splitting process. ZnO BNW was first synthesized by hydrothermal method...Photoanode of ZnO branched nanowires, BNW, doped with nitrogen was fabricated to be used in photochemical cell for hydrogen generation from water splitting process. ZnO BNW was first synthesized by hydrothermal method. Followed by time-control DC glow discharge plasma treatment, to optimize nitrogen doping into nanowire structure. Via X-ray photoelectron spectroscopy （XPS） results, BNW with up to 25% atomic ratio of N to Zn was achieved by plasma treatment. XPS studies confirm nitrogen distribution into ZnO BNW as N substitution at O sites of ZnO nanowires and as well screened molecular nitrogen. Modified BNW electronic structure reflected into flat band potential that increased negatively with N contain into BNW cal studies were demonstrated upon dark and illumination at various power densities. Increasing N contain into BNW leads to increase photocurrent on PEC （Photo-electrochemical cell）. Hydrogen generation from water splitting efficiency of 0.3% was achieved for BNW doped with 25% N.展开更多
Reduced graphene oxide(RGO)assisted TiO2 composite photocatalysts have attracted increased attention because of their high photocatalytic performance under both UV-and visible-light irradiation.However,the correspondi...Reduced graphene oxide(RGO)assisted TiO2 composite photocatalysts have attracted increased attention because of their high photocatalytic performance under both UV-and visible-light irradiation.However,the corresponding properties under the long wavelength irradiation is far from expected.In this study,a series of RGO samples with well-designed N impurity and optimized surface functional groups are prepared and employed during hybridization with TiO2(named N-RGO/TiO2).The coupling between the doped N atoms and surface functional groups is analyzed based on the resulting photocatalytic performances,and the specific mechanism is revealed by the EPR,IR and lifetime of the photoinduced electrons.After comparing the corresponding performances of the RGO/TiO2 and RGO/N-TiO2 specimens,the results show that the surface functional groups of the RGO serve as a precondition to achieveπ-d coupling between the graphene basal plane and TiO2 nanoparticles,while N atoms in the RGO enhance the resulting photoactivity under a long wavelength range(>510 nm).The findings provide a potential approach to promote the photocatalytic properties of graphene-based composite photocatalysts with the low-energy incident photons.展开更多
The defect regulation and p-n heterojunction of composites have gained significant attention due to their potential applications.Nitrogen(N)as doping heteroatoms and perylene-3,4,9,10-tetracarboximide(PDINH)as an appr...The defect regulation and p-n heterojunction of composites have gained significant attention due to their potential applications.Nitrogen(N)as doping heteroatoms and perylene-3,4,9,10-tetracarboximide(PDINH)as an appropriate n-type semiconductor were innovatively and reasonably selected to enhance the photocatalytic performance of pristine p-type cuprous oxide(Cu_(2)O).In this study,the defect regula-tion of N doping(1)achieved the small-size effect of Cu_(2)O,(2)optimized the electron features,and(3)improved the kinetics of reactive oxygen species.The p-n heterojunction with PDINH was developed to sharply improve the light utilization of Cu_(2)O,from the UV region to the near-infrared region.As expected,the optimized Cu_(2)N_(x)O_(1–x)/PDINH(x=0.02)exhibited excellent long-term photocatalytic antibacterial ac-tivities,with antibacterial rates exceeding 91%against Staphylococcus aureus and Pseudomonas aeruginosa.Defect regulation and p-n heterojunction of Cu_(2)O-based composites thus provide a great deal of potential for future advancements in photocatalysis.展开更多
By using the first-principles calculations, the electronic Structure and quantum transport properties of metallic carbon nanotubes with B/N pairs co-doping have been investigated. It is shown that the total energies o...By using the first-principles calculations, the electronic Structure and quantum transport properties of metallic carbon nanotubes with B/N pairs co-doping have been investigated. It is shown that the total energies of metallic carbon nanotubes are sensitive to the doping sites of the B/N pairs. The energy gaps of the doped metallic carbon nanotubes decrease with decreasing the concentration of the B/N pair not only along the tube axis but also around the tube. Moreover, the I-V characteristics and transmissions of the doped tubes are studied. Our results reveal that the conducting ability of the doped tube decreases with increasing the concentrations of the B/N pairs due to symmetry breaking of the system. This fact opens a new way to modulate band structures of metallic carbon nanotubes by doping B/N pair with suitable concentration and the novel characteristics are potentially useful in future applications.展开更多
Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru ...Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.展开更多
Hard carbon (HC) is perceived as an anode candidate for sodium-ion batteries and potassium-ion batteries due to its disordered structure and cost-effectiveness,yet its capacity is restricted by limited active sites.He...Hard carbon (HC) is perceived as an anode candidate for sodium-ion batteries and potassium-ion batteries due to its disordered structure and cost-effectiveness,yet its capacity is restricted by limited active sites.Heteroatom-induced defect engineering of HC is commonly applied for enhancing its reversible capacity,but high heteroatom doping (>14 at%) is challenging due to the absence of heteroatoms in most biomasses.Not only that,the heteroatom doping strategy is also bothered with high diffusion barriers toward Na^(+)/K^(+).Herein,based on a rationally selected low-cost precursor (sodium alginateDmelamineDNaCl),a new HC with high-level N,O heteroatom dopants (21.4 at%) and well-regulated porous structure has been constructed via acylating and controllable pore engineering.Experimental proof and theoretical calculations have been conducted to clarify the influence of heteroatom dopants and porous structures on the ion storage behavior of the designed HC.The rich N,O co-doping could enable efficient Na+/K+adsorption and enhanced electron transfer behavior.Besides,benefiting from the hierarchical porous structures (micro to macropores),the interfacial reaction kinetics and electrochemical behavior can be boosted.Particularly,the optimized N,O dualdoped hierarchical porous HC (NO-HPHC-1,0.285 mol L-1NaCl in precursor) with abundant defects from macropores and moderate micropores make it exhibit excellent Na^(+)storage:127 mAh g^(-1)at 0.5 A g^(-1)even after 2000 cycles.Meanwhile,the superiority of NO-HPHC-1 can be well maintained for K^(+)storage with a reversible capacity of 199 mAh g^(-1)at 0.1 A g^(-1).More importantly,the diverse Na^(+)/K^(+)storage behaviors have been elucidated.展开更多
A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas,...A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas, total pore volumes and microporepercentages of the CO_2-activated samples evidently increase with increasing activation temperature from 800 to950 °C, while the N contents show a contrary trend from7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample(CANHCS-950) has the largest surface area(2072 m^2 g^(-1)), pore volume(1.96 cm^3 g^(-1)), hierarchical micro-mesopore distributions(1.2, 2.6 and 6.2 nm), hollow macropore cores(*91 nm)and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions.Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction(ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4 e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications.展开更多
The exploration of low-cost and high-performance transition metal oxides/carbon(TMOs/C)-based anodes to replace commercial graphite is still a huge challenge for the development of lithium-ion batteries(LIBs).In this ...The exploration of low-cost and high-performance transition metal oxides/carbon(TMOs/C)-based anodes to replace commercial graphite is still a huge challenge for the development of lithium-ion batteries(LIBs).In this work,MnO@N-doped hollow carbon nanotubes(MnO@NHCNT-v,v refers to the adding volume of pyrrole)hybrids are successfully prepared by a facile selftemplate strategy using Mn3O4 nanotubes(Mn3O4 NT)and pyrrole(PY)as the precursors.The morphology,structure and composition of these MnO@NHCNT-v samples are systematically investigated.And the effect of PY adding amounts on the synthesis of MnO@NHCNT-v samples is also explored.The results show that the Mn_(3)O_(4) NT works as a self-template,which releases Mn3+and guides the growth of polypyrrole(PPY)on Mn_(3)O_(4) NT.Meanwhile,it is demonstrated that the synthesis of MnO@NHCNTv hybrids can be well regulated by the added PY amounts.As a result,MnO@NHCNT-1 hybrid not only makes a good balance on the proportion of MnO and carbon matrix but also simultaneously obtains unique peapod-like structure and successful N doping in NHCNT,resulting in good electrical contact between the two components,enhanced chemical binding by Mn-N-C bonds and enough void space inside its microstructure.Benefitting from these merits,the resulting MnO@NHCNT-1 hybrid exhibits outstanding cycling stability and rate capability when used as a LIBs anode.Our work offers a good guidance on the design and preparation of low-price and high-performance TMOs/C-based LIBs anodes.展开更多
Due to its larger ionic radius,further studies are needed before graphite can be used as an anode for sodium/potassium-ion batteries(SIBs/KIBs).It is believed that doping and increasing the layer spacing can improve t...Due to its larger ionic radius,further studies are needed before graphite can be used as an anode for sodium/potassium-ion batteries(SIBs/KIBs).It is believed that doping and increasing the layer spacing can improve the Na+/K+storage.Herein,S/N co-doped graphite nanosheets(GNS)with an enlarged interlayer spacing of 0.39 nm were prepared via exfoliation with three-roll milling(TRM)combined with thiourea heated at different temperatures.This method generates abundant defects and active sites for GNS,as well as facilitates rapid access and transport of electrolytes and electrons/ions.The electrochemical results show that the S/N-doped GNS exfoliated 15 times and heated at 600°C(SNGNS15-600)with thiourea as the electrode delivers a discharge capacity of 94 mAh g–1 over 6000 cycles at 10 A g–1 with an enhanced rate capability and stable performance for application in SIBs.Calculations using density functional theory show that the increased interlayer spacing by TRM and S,N co-doping enhances the adsorption energies of Na+on graphite,thus improving the Na+storage.As the anode for KIBs,the SNGNS15-600 electrode has a capacity of 142 mAh g–1 after 5000 cycles at 0.5 A g–1.This study provides an essential theoretical basis for the effective exfoliation of layered graphite-based materials and their applications in energy storage.展开更多
The design of pore structure is the key factor for the performance of porous carbon spheres.In this wo rk,novel micron-sized colloidal crystal microspheres consisting of fibrous silica(F-SiO_(2)) nanoparticles are fir...The design of pore structure is the key factor for the performance of porous carbon spheres.In this wo rk,novel micron-sized colloidal crystal microspheres consisting of fibrous silica(F-SiO_(2)) nanoparticles are firstly prepared by water-evapo ration-induced self-assembly of F-SiO_(2) nanoparticles in the droplets of an inverse emulsion system to be used as sacrificial templates.Acrylonitrile(AN) was infiltrated in the voids of the F-SiO_(2) colloidal crystal microspheres,and in-situ induced by ^(60)Co γ-ray to polymerize into polyacrylonitrile(PAN).After the PAN-infiltrated F-SiO_(2) colloidal crystal microspheres were carbonized and etched with HF solution,novel micron-sized inverse-opal N-doped carbon(IO-NC) microspheres consisting of hollow carbon nanoparticles with a hierarchical macro/meso-porous inner surface were obtained.The IO-NC microspheres have a specific surface area as high as 266.4 m^(2)/g and a molar ratio of C/N of 5.They have a good dispersibility in water,and show a high adsorption capacity towards rhodamine B(RhB) up to 137.28 mg/(g microsphe re).This work offers a way to obtain novel micron-sized hierarchical macro/meso-porous N-doped carbon microspheres,which opens a new idea to prepare high-performance hierarchical porous carbon materials.展开更多
A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed...A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed crystal anatase-rutile TiO_(2)(ar-TiO_(2)) nanosphere is first prepared by oxidizing Ti using H_(2)O_(2), and then is etched by NH_(3)·H_(2)O to form(NH_(4))2TiO_(3)nanobranches, which is converted into a-TiO_(2)@N-TiO_(2)following an ambient annealing process. The diameter of a-TiO_(2)core is ~500 nm, and the thickness of NTiO_(2)branched shell is ~100 nm with gradually increased N concentration from the bottom to the edge.Ultra-thin amorphous coating layers on the branches are also observed. The morphology of the composites could be further tuned by the amount of NH_(3)·H_(2)O, and its effect on the photocatalytic performance is also investigated. The optimized a-TiO_(2)@N-TiO_(2)shows an outstanding hydrogen evolution rate of 308.1 μmol g^(-1)h^(-1)under air mass(AM) 1.5 illumination, and also exhibits highly active in photocatalytic degradation of various refractory organic pollutants, including organic dyes, phenols, antibiotics,and personal care products, with removal ratios higher than 96% after 2 h operation. This can be due to the gradient-doped N-TiO_(2)nanobranches, which not only provide bending band structure and defect level derived from the N impurities and O vacancies, resulting the formation of n-n+heterojunctions to improve the charge separation, but also enhance the charge transfer at the liquid-solid interface due to the numerous nanobranches and amorphous coating layers.展开更多
Tailored design and synthesis of high-quality electrocatalysts is vital for the advancement of oxygen evolution reaction(OER).Herein,we report a powerful puffing method to fabricate hierarchical porous N-doped carbon ...Tailored design and synthesis of high-quality electrocatalysts is vital for the advancement of oxygen evolution reaction(OER).Herein,we report a powerful puffing method to fabricate hierarchical porous N-doped carbon with numerous embedded Ni nanoparticles.Interestingly,during the puffing and annealing process,rice precursor with N and Ni sources can be in-situ converted into Ni-embedded N-doped porous carbon(N-PC/Ni) composite.The obtained N-PC/Ni composite possesses a cross-linked porous architecture containing conductive carbon backbone and active Ni nanoparticles electrocatalysts for OER.The pore formation in N-PC/Ni composite is also proposed because of carbothermic reduction.The N-PC/Ni composite is fully studied as electrocatalysts for OER.Due to increased active surface area,enhanced electronic conductivity and reactivity,the designed N-PC/Ni composite exhibits superior OER performance with a low Tafel slope(~88 mV/dec) and a low overpotential as well as excellent long-term stability in alkaline solution.Our proposed rational design strategy may provide a new way to construct other advanced metal/heteroatom-doped composites for widespread application in electrocatalysis.展开更多
A series of nitrogen-doped CoAlO(N-CoAlO)were constructed by a hydrothermal route combined with a controllable NH_(3) treatment strategy.The effects of NH_(3) treatment on the physico-chemical properties and oxidation...A series of nitrogen-doped CoAlO(N-CoAlO)were constructed by a hydrothermal route combined with a controllable NH_(3) treatment strategy.The effects of NH_(3) treatment on the physico-chemical properties and oxidation activities of N-Co AlO catalysts were investigated.In comparison to CoAlO,a smallest content decrease in surface Co^(3+)(serving as active sites)while a largest increased amount of surface Co^(2+)(contributing to oxygen species)are obtained over N-Co AlO/4h among the N-CoAlO catalysts.Meanwhile,a maximum N doping is found over N-CoAlO/4h.As a result,N-CoAlO/4h(under NH_(3) treatment at 400℃ for 4 hr)with rich oxygen vacancies shows optimal catalytic activity,with a T90(the temperature required to reach a 90% conversion of propane)at 266℃.The more oxygen vacancies are caused by the co-operative effects of N doping and suitable reduction of Co^(3+) for NCoAlO/4h,leading to an enhanced oxygen mobility,which in turn promotes C_(3)H_(8) total oxidation activity dominated by Langmuir-Hinshelwood mechanism.Moreover,in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTs)analysis shows that N doping facilities the decomposition of intermediate species(propylene and formate)into CO_(2)over the catalyst surface of N-CoAlO/4h more easily.Our reported design in this work will provide a promising way to develop abundant oxygen vacancies of Co-based catalysts derived from hydrotalcites by a simple NH_(3) treatment.展开更多
The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilat...The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilation analysis （PAS）. Upon N doping, a twofold enhancement of the saturation magnetization is observed. Apparently, this enhancement is not related to an increase in oxygen vacancy, rather to unpaired 3d electrons in Ti3＋, arising from titanium vacancies and the replacement of O with N atoms in the futile structure. The production of titanium vacancies can enhance the room temperature ferromagnetism （RTFM）, and substitution of O with N is the onset of ferromagnetism by inducing relatively strong ferromagnetic ordering.展开更多
Exploring low-cost and high-performance catalysts for oxygen evolution reaction(OER)remains to be a great challenge.Iridium-based perovskite oxide has large potential in OER because of its intrinsic activity and outst...Exploring low-cost and high-performance catalysts for oxygen evolution reaction(OER)remains to be a great challenge.Iridium-based perovskite oxide has large potential in OER because of its intrinsic activity and outstanding physicochemical properties.In this study,iridium-doped strontium titanate(Ir-STO)solution is brushed on a Ti sheet by the traditional method to obtain the Ir-STO/Ti electrodes after being calcined at a high temperature.The microstructure and electrocatalysis properties of the Ir-STO are further modified by a facile and scalable NH_(3)-plasma strategy.In addition to the doping of Ir,the NH_(3) plasma treatment further results in N-doping into Ir-STO,which enriches active species and causes oxygen vacancies near doped sites.The resulting N,Ir-STO/Ti electrode reveals excellent acidic OER activity with the lowest overpotential of 390 m V at 10 m A/cm^(2) and the smallest Tafel slope of 140 mV/dec after 10-min plasma treatment.Therefore,the great potential of activated N,Ir-STO/Ti is regarded as a catalyst for the OER,and thus making a new opportunity for developing other perovskite catalysts via NH_(3) plasma treatment.展开更多
Recently electrochemical synthesis of H_(2)O_(2)through oxygen reduction reaction(ORR)via 2e^(-)pathway is considered as a green and on-site route.However,it still remains a big challenge for fabricating novel metal-f...Recently electrochemical synthesis of H_(2)O_(2)through oxygen reduction reaction(ORR)via 2e^(-)pathway is considered as a green and on-site route.However,it still remains a big challenge for fabricating novel metal-free catalysts under acidic solutions,since it suffers from high overpotential due to the intrinsically week*OOH adsorption.Herein,a co-doped carbon nanosheet(O/N–C)catalyst toward regulating O and N content was synthesized for improving the selectivity and activity of H_(2)O_(2)electrosynthesis process.The O/N–C exhibits outstanding 2e-ORR performance with low onset potential of 0.4 V(vs.RHE)and a selectivity of 92.4%in 0.1 mol/L HClO_(4)solutions.The in situ electrochemical impedance spectroscopy(EIS)tests reveals that the N incorporation contributes to the fast ORR kinetics.The density functional theory(DFT)calculations demonstrate that the binding strength of*OOH was optimized by the co-doping of oxygen and nitrogen at certain content,and the O/N–C–COOH site exhibits a lower theoretical overpotential for H_(2)O_(2)formation than O–C–COOH site.Furthermore,the promoted kinetics for typical organic dye degradation in simultaneous electron-Fenton process on O/N–C catalyst was demonstrated particularly for broadening its environmental application.展开更多
Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-dope...Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-doped Ni-Co-Mn(N-NCM)electrocatalyst from waste LIBs,for robust oxygen evolution application.Lithium-rich solution and NCM oxides are effectively separated from ternary cathode materials by sulfation roasting and low-temperature water leaching approach,in which the recovery efficiency of Li metal reaches nearly 100%.By facile NH_(3)treatment,the incorporation of N into NCM significantly increases the ratio of low-valence state Co^(2+)and Mn^(2+),and the formed Mn-N bond benefits the surface catalytic kinetics.Meanwhile,the N doping induces lattice expansion of the NCM,triggering tensile stress to favor the adsorption of the reactant.Thus,the optimized N-NCM electrocatalyst exhibits the superior overpotentials of 256 and 453 mV to achieve the current density of 10 and 100 mA/cm^(2),respectively,with a low Tafel slope of 37.3 mV/dec.This work provides a fresh avenue for recycling spent LIBs in the future to achieve sustainable development.展开更多
Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vi...Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vital to explore alternative catalysts without mercury. We report here that N-doped carbon can catalyze directly transformation of acetylene to vinyl chloride. Particularly, N-doped high surface area mesoporous carbon exhibits a rather high activity with the acetylene conversion reaching 77% and vinyl chloride selectivity above 98% at a space velocity of 1.0 mL.min-l.g-1 and 200 ~C. It delivers a stable performa℃nce within a test period of 100h and no obvious deactivation is observed, demonstrating potentials to substitute the notoriously toxic mercuric chloride catalyst.展开更多
We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent ...We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent catalytic performance in acetylene hydrochlorination.Herein,we examined the activity of Au supported on N‐MC(Au/N‐MC)and compared it with that of Au supported on nitrogen‐free mesoporous carbon(Au/MC).The acetylene conversion of Au/N‐MC was 50%at 180°C with an acetylene space velocity of 600 h–1 and VHCl/VC2H2 of 1.1,which was double the activity of Au/MC(25%).The introduced nitrogen atoms acted as anchor sites that stabilized the Au3+species and inhibited the reduction of Au3+to Au0 during the preparation of Au/N‐MC catalysts.展开更多
The discontinuity of new types of clean energy,such as wind power and solar cells, has promoted the development of large-scale energy storage systems(EES).Rechargeable aqueous zinc-ion batteries(ZIBs) have received ex...The discontinuity of new types of clean energy,such as wind power and solar cells, has promoted the development of large-scale energy storage systems(EES).Rechargeable aqueous zinc-ion batteries(ZIBs) have received extensive attention due to their inherent safety and low cost. At this stage, the performance of ZIBs is still limited by cathode materials. In this work, we have constructed a ZIBs cathode material-V_(2)O_(3)@N–C, through surface coating and N atom doping. The N-doped carbon coating endows V_(2)O_(3)@N–C with excellent structural stability and enhances its electrical conductivity. As a result,V_(2)O_(3)@N–C cathode delivers exceptional reversible of Zn^(2+) intercalation/deintercalation. The fabricated Zn/V_(2)O_(3)@N–C batteries exhibit high capacity of 274.6 mAh·g^(-1) at 5 A·g^(-1) and excellent capacity retention of 94% after 2000 cycles. The reversible intercalation/deintercalation of Zn^(2+) in the V_(2)O_(3)@N–C cathode is proved by ex-situ testing methods. It is believed that this work should inject new vitality into the development of ZIBs cathode.展开更多
文摘Photoanode of ZnO branched nanowires, BNW, doped with nitrogen was fabricated to be used in photochemical cell for hydrogen generation from water splitting process. ZnO BNW was first synthesized by hydrothermal method. Followed by time-control DC glow discharge plasma treatment, to optimize nitrogen doping into nanowire structure. Via X-ray photoelectron spectroscopy （XPS） results, BNW with up to 25% atomic ratio of N to Zn was achieved by plasma treatment. XPS studies confirm nitrogen distribution into ZnO BNW as N substitution at O sites of ZnO nanowires and as well screened molecular nitrogen. Modified BNW electronic structure reflected into flat band potential that increased negatively with N contain into BNW cal studies were demonstrated upon dark and illumination at various power densities. Increasing N contain into BNW leads to increase photocurrent on PEC （Photo-electrochemical cell）. Hydrogen generation from water splitting efficiency of 0.3% was achieved for BNW doped with 25% N.
基金supported by the National Natural Science Foundation of China(Grant Nos.51506012 and 51706023)the Changzhou City Science and Technology Support Program(Grant No.CE20185043)。
文摘Reduced graphene oxide(RGO)assisted TiO2 composite photocatalysts have attracted increased attention because of their high photocatalytic performance under both UV-and visible-light irradiation.However,the corresponding properties under the long wavelength irradiation is far from expected.In this study,a series of RGO samples with well-designed N impurity and optimized surface functional groups are prepared and employed during hybridization with TiO2(named N-RGO/TiO2).The coupling between the doped N atoms and surface functional groups is analyzed based on the resulting photocatalytic performances,and the specific mechanism is revealed by the EPR,IR and lifetime of the photoinduced electrons.After comparing the corresponding performances of the RGO/TiO2 and RGO/N-TiO2 specimens,the results show that the surface functional groups of the RGO serve as a precondition to achieveπ-d coupling between the graphene basal plane and TiO2 nanoparticles,while N atoms in the RGO enhance the resulting photoactivity under a long wavelength range(>510 nm).The findings provide a potential approach to promote the photocatalytic properties of graphene-based composite photocatalysts with the low-energy incident photons.
基金supported by the National Natural Science Foundation Joint Fund(Nos.U1806223 and U2106226)the National Natural Science Foundation of China(No.52371081)the Key Technology Research and Development Program of Shandong Province(No.2020CXGC010703).
文摘The defect regulation and p-n heterojunction of composites have gained significant attention due to their potential applications.Nitrogen(N)as doping heteroatoms and perylene-3,4,9,10-tetracarboximide(PDINH)as an appropriate n-type semiconductor were innovatively and reasonably selected to enhance the photocatalytic performance of pristine p-type cuprous oxide(Cu_(2)O).In this study,the defect regula-tion of N doping(1)achieved the small-size effect of Cu_(2)O,(2)optimized the electron features,and(3)improved the kinetics of reactive oxygen species.The p-n heterojunction with PDINH was developed to sharply improve the light utilization of Cu_(2)O,from the UV region to the near-infrared region.As expected,the optimized Cu_(2)N_(x)O_(1–x)/PDINH(x=0.02)exhibited excellent long-term photocatalytic antibacterial ac-tivities,with antibacterial rates exceeding 91%against Staphylococcus aureus and Pseudomonas aeruginosa.Defect regulation and p-n heterojunction of Cu_(2)O-based composites thus provide a great deal of potential for future advancements in photocatalysis.
基金supported by the Major Research Plan from the Ministry of Science and Technology of China (Grant No. 2011CB921900)the China Postdoctoral Science Special Foundation (Grant No. 201003009)+2 种基金the China Postdoctoral Science Foundation (GrantNo. 20090460145)the Fundamental Research Funds for the Central Universities (Grant No. 201012200053)the Science and Technology Program of Hunan Province of China (Grant No. 2010DFJ411)
文摘By using the first-principles calculations, the electronic Structure and quantum transport properties of metallic carbon nanotubes with B/N pairs co-doping have been investigated. It is shown that the total energies of metallic carbon nanotubes are sensitive to the doping sites of the B/N pairs. The energy gaps of the doped metallic carbon nanotubes decrease with decreasing the concentration of the B/N pair not only along the tube axis but also around the tube. Moreover, the I-V characteristics and transmissions of the doped tubes are studied. Our results reveal that the conducting ability of the doped tube decreases with increasing the concentrations of the B/N pairs due to symmetry breaking of the system. This fact opens a new way to modulate band structures of metallic carbon nanotubes by doping B/N pair with suitable concentration and the novel characteristics are potentially useful in future applications.
基金supported by the Development Project of Youth Innovation Team in Shandong Colleges and Universities(No.2019KJC031)the Natural Science Foundation of Shandong Province(Nos.ZR2019MB064,ZR2021MB122 and ZR2022MB137)the Doctoral Program of Liaocheng University(No.318051608).
文摘Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.
基金financially supported by the National Natural Science Foundation of China(Nos.52072193,U22A20131,U22A20250,and 52361165657)Shandong Provincial Natural Science Foundation(Nos.ZR2021JQ16 and ZR2023YQ040)the State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(No.KF2217)
文摘Hard carbon (HC) is perceived as an anode candidate for sodium-ion batteries and potassium-ion batteries due to its disordered structure and cost-effectiveness,yet its capacity is restricted by limited active sites.Heteroatom-induced defect engineering of HC is commonly applied for enhancing its reversible capacity,but high heteroatom doping (>14 at%) is challenging due to the absence of heteroatoms in most biomasses.Not only that,the heteroatom doping strategy is also bothered with high diffusion barriers toward Na^(+)/K^(+).Herein,based on a rationally selected low-cost precursor (sodium alginateDmelamineDNaCl),a new HC with high-level N,O heteroatom dopants (21.4 at%) and well-regulated porous structure has been constructed via acylating and controllable pore engineering.Experimental proof and theoretical calculations have been conducted to clarify the influence of heteroatom dopants and porous structures on the ion storage behavior of the designed HC.The rich N,O co-doping could enable efficient Na+/K+adsorption and enhanced electron transfer behavior.Besides,benefiting from the hierarchical porous structures (micro to macropores),the interfacial reaction kinetics and electrochemical behavior can be boosted.Particularly,the optimized N,O dualdoped hierarchical porous HC (NO-HPHC-1,0.285 mol L-1NaCl in precursor) with abundant defects from macropores and moderate micropores make it exhibit excellent Na^(+)storage:127 mAh g^(-1)at 0.5 A g^(-1)even after 2000 cycles.Meanwhile,the superiority of NO-HPHC-1 can be well maintained for K^(+)storage with a reversible capacity of 199 mAh g^(-1)at 0.1 A g^(-1).More importantly,the diverse Na^(+)/K^(+)storage behaviors have been elucidated.
基金the financial support from the National Key Research and Development Program of China(2016YFB0700204)NSFC(51502327,51602332)+1 种基金Science and Technology Commission of Shanghai Municipality(15520720400,15YF1413800,14DZ2261203 and 16DZ2260603)Key Project for Young Researcher of State Key Laboratory of High Performance Ceramics and Superfine Microstructure and One Hundred Talent Plan of Chinese Academy of Sciences
文摘A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas, total pore volumes and microporepercentages of the CO_2-activated samples evidently increase with increasing activation temperature from 800 to950 °C, while the N contents show a contrary trend from7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample(CANHCS-950) has the largest surface area(2072 m^2 g^(-1)), pore volume(1.96 cm^3 g^(-1)), hierarchical micro-mesopore distributions(1.2, 2.6 and 6.2 nm), hollow macropore cores(*91 nm)and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions.Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction(ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4 e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications.
基金financially supported by the National Natural Science Foundation of China(Nos.52171207,52104301 and 52072120)the Science&Technology talents lifting project of Hunan Province(No.2022TJ-N16)the Scientific Research Fund of Hunan Provincial Education Department,China(Nos.21A0392,21B0406 and 19A203)。
文摘The exploration of low-cost and high-performance transition metal oxides/carbon(TMOs/C)-based anodes to replace commercial graphite is still a huge challenge for the development of lithium-ion batteries(LIBs).In this work,MnO@N-doped hollow carbon nanotubes(MnO@NHCNT-v,v refers to the adding volume of pyrrole)hybrids are successfully prepared by a facile selftemplate strategy using Mn3O4 nanotubes(Mn3O4 NT)and pyrrole(PY)as the precursors.The morphology,structure and composition of these MnO@NHCNT-v samples are systematically investigated.And the effect of PY adding amounts on the synthesis of MnO@NHCNT-v samples is also explored.The results show that the Mn_(3)O_(4) NT works as a self-template,which releases Mn3+and guides the growth of polypyrrole(PPY)on Mn_(3)O_(4) NT.Meanwhile,it is demonstrated that the synthesis of MnO@NHCNTv hybrids can be well regulated by the added PY amounts.As a result,MnO@NHCNT-1 hybrid not only makes a good balance on the proportion of MnO and carbon matrix but also simultaneously obtains unique peapod-like structure and successful N doping in NHCNT,resulting in good electrical contact between the two components,enhanced chemical binding by Mn-N-C bonds and enough void space inside its microstructure.Benefitting from these merits,the resulting MnO@NHCNT-1 hybrid exhibits outstanding cycling stability and rate capability when used as a LIBs anode.Our work offers a good guidance on the design and preparation of low-price and high-performance TMOs/C-based LIBs anodes.
基金supported by the Natural Science Foundation of China(Nos.51862024 and 51962023)the Key Research and Development Program of Jiangxi Province(No.20203BBE53066).
文摘Due to its larger ionic radius,further studies are needed before graphite can be used as an anode for sodium/potassium-ion batteries(SIBs/KIBs).It is believed that doping and increasing the layer spacing can improve the Na+/K+storage.Herein,S/N co-doped graphite nanosheets(GNS)with an enlarged interlayer spacing of 0.39 nm were prepared via exfoliation with three-roll milling(TRM)combined with thiourea heated at different temperatures.This method generates abundant defects and active sites for GNS,as well as facilitates rapid access and transport of electrolytes and electrons/ions.The electrochemical results show that the S/N-doped GNS exfoliated 15 times and heated at 600°C(SNGNS15-600)with thiourea as the electrode delivers a discharge capacity of 94 mAh g–1 over 6000 cycles at 10 A g–1 with an enhanced rate capability and stable performance for application in SIBs.Calculations using density functional theory show that the increased interlayer spacing by TRM and S,N co-doping enhances the adsorption energies of Na+on graphite,thus improving the Na+storage.As the anode for KIBs,the SNGNS15-600 electrode has a capacity of 142 mAh g–1 after 5000 cycles at 0.5 A g–1.This study provides an essential theoretical basis for the effective exfoliation of layered graphite-based materials and their applications in energy storage.
基金supported by the National Natural Science Foundation of China (Nos.51573174,51773189 and 51973205)Science Challenge Project (No.TZ2018004)the Fundamental Research Funds for the Central Universities (No.WK3450000004)。
文摘The design of pore structure is the key factor for the performance of porous carbon spheres.In this wo rk,novel micron-sized colloidal crystal microspheres consisting of fibrous silica(F-SiO_(2)) nanoparticles are firstly prepared by water-evapo ration-induced self-assembly of F-SiO_(2) nanoparticles in the droplets of an inverse emulsion system to be used as sacrificial templates.Acrylonitrile(AN) was infiltrated in the voids of the F-SiO_(2) colloidal crystal microspheres,and in-situ induced by ^(60)Co γ-ray to polymerize into polyacrylonitrile(PAN).After the PAN-infiltrated F-SiO_(2) colloidal crystal microspheres were carbonized and etched with HF solution,novel micron-sized inverse-opal N-doped carbon(IO-NC) microspheres consisting of hollow carbon nanoparticles with a hierarchical macro/meso-porous inner surface were obtained.The IO-NC microspheres have a specific surface area as high as 266.4 m^(2)/g and a molar ratio of C/N of 5.They have a good dispersibility in water,and show a high adsorption capacity towards rhodamine B(RhB) up to 137.28 mg/(g microsphe re).This work offers a way to obtain novel micron-sized hierarchical macro/meso-porous N-doped carbon microspheres,which opens a new idea to prepare high-performance hierarchical porous carbon materials.
基金supported by the National Natural Science Foundation of China (No. 52170083)the Excellent Youth Fund Project of Natural Science Foundation of Hunan Province (No.2021JJ20007)the Research Foundation of Education Bureau of Hunan Province,China (No. 21B0441)。
文摘A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed crystal anatase-rutile TiO_(2)(ar-TiO_(2)) nanosphere is first prepared by oxidizing Ti using H_(2)O_(2), and then is etched by NH_(3)·H_(2)O to form(NH_(4))2TiO_(3)nanobranches, which is converted into a-TiO_(2)@N-TiO_(2)following an ambient annealing process. The diameter of a-TiO_(2)core is ~500 nm, and the thickness of NTiO_(2)branched shell is ~100 nm with gradually increased N concentration from the bottom to the edge.Ultra-thin amorphous coating layers on the branches are also observed. The morphology of the composites could be further tuned by the amount of NH_(3)·H_(2)O, and its effect on the photocatalytic performance is also investigated. The optimized a-TiO_(2)@N-TiO_(2)shows an outstanding hydrogen evolution rate of 308.1 μmol g^(-1)h^(-1)under air mass(AM) 1.5 illumination, and also exhibits highly active in photocatalytic degradation of various refractory organic pollutants, including organic dyes, phenols, antibiotics,and personal care products, with removal ratios higher than 96% after 2 h operation. This can be due to the gradient-doped N-TiO_(2)nanobranches, which not only provide bending band structure and defect level derived from the N impurities and O vacancies, resulting the formation of n-n+heterojunctions to improve the charge separation, but also enhance the charge transfer at the liquid-solid interface due to the numerous nanobranches and amorphous coating layers.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LY17E040001)。
文摘Tailored design and synthesis of high-quality electrocatalysts is vital for the advancement of oxygen evolution reaction(OER).Herein,we report a powerful puffing method to fabricate hierarchical porous N-doped carbon with numerous embedded Ni nanoparticles.Interestingly,during the puffing and annealing process,rice precursor with N and Ni sources can be in-situ converted into Ni-embedded N-doped porous carbon(N-PC/Ni) composite.The obtained N-PC/Ni composite possesses a cross-linked porous architecture containing conductive carbon backbone and active Ni nanoparticles electrocatalysts for OER.The pore formation in N-PC/Ni composite is also proposed because of carbothermic reduction.The N-PC/Ni composite is fully studied as electrocatalysts for OER.Due to increased active surface area,enhanced electronic conductivity and reactivity,the designed N-PC/Ni composite exhibits superior OER performance with a low Tafel slope(~88 mV/dec) and a low overpotential as well as excellent long-term stability in alkaline solution.Our proposed rational design strategy may provide a new way to construct other advanced metal/heteroatom-doped composites for widespread application in electrocatalysis.
基金financially supported by the National Key Research and Development Program of China(No.2019YFC1904500)Young Top Talents of Fujian Young Eagle Program。
文摘A series of nitrogen-doped CoAlO(N-CoAlO)were constructed by a hydrothermal route combined with a controllable NH_(3) treatment strategy.The effects of NH_(3) treatment on the physico-chemical properties and oxidation activities of N-Co AlO catalysts were investigated.In comparison to CoAlO,a smallest content decrease in surface Co^(3+)(serving as active sites)while a largest increased amount of surface Co^(2+)(contributing to oxygen species)are obtained over N-Co AlO/4h among the N-CoAlO catalysts.Meanwhile,a maximum N doping is found over N-CoAlO/4h.As a result,N-CoAlO/4h(under NH_(3) treatment at 400℃ for 4 hr)with rich oxygen vacancies shows optimal catalytic activity,with a T90(the temperature required to reach a 90% conversion of propane)at 266℃.The more oxygen vacancies are caused by the co-operative effects of N doping and suitable reduction of Co^(3+) for NCoAlO/4h,leading to an enhanced oxygen mobility,which in turn promotes C_(3)H_(8) total oxidation activity dominated by Langmuir-Hinshelwood mechanism.Moreover,in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTs)analysis shows that N doping facilities the decomposition of intermediate species(propylene and formate)into CO_(2)over the catalyst surface of N-CoAlO/4h more easily.Our reported design in this work will provide a promising way to develop abundant oxygen vacancies of Co-based catalysts derived from hydrotalcites by a simple NH_(3) treatment.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.61006066)
文摘The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilation analysis （PAS）. Upon N doping, a twofold enhancement of the saturation magnetization is observed. Apparently, this enhancement is not related to an increase in oxygen vacancy, rather to unpaired 3d electrons in Ti3＋, arising from titanium vacancies and the replacement of O with N atoms in the futile structure. The production of titanium vacancies can enhance the room temperature ferromagnetism （RTFM）, and substitution of O with N is the onset of ferromagnetism by inducing relatively strong ferromagnetic ordering.
基金Project supported by the Priority Academic Program Development(PAPD)Program of Jiangsu Higher Education Institutions,Jiangsu Province,Chinathe National Natural Science Foundation of China(Grant No.11675117)。
文摘Exploring low-cost and high-performance catalysts for oxygen evolution reaction(OER)remains to be a great challenge.Iridium-based perovskite oxide has large potential in OER because of its intrinsic activity and outstanding physicochemical properties.In this study,iridium-doped strontium titanate(Ir-STO)solution is brushed on a Ti sheet by the traditional method to obtain the Ir-STO/Ti electrodes after being calcined at a high temperature.The microstructure and electrocatalysis properties of the Ir-STO are further modified by a facile and scalable NH_(3)-plasma strategy.In addition to the doping of Ir,the NH_(3) plasma treatment further results in N-doping into Ir-STO,which enriches active species and causes oxygen vacancies near doped sites.The resulting N,Ir-STO/Ti electrode reveals excellent acidic OER activity with the lowest overpotential of 390 m V at 10 m A/cm^(2) and the smallest Tafel slope of 140 mV/dec after 10-min plasma treatment.Therefore,the great potential of activated N,Ir-STO/Ti is regarded as a catalyst for the OER,and thus making a new opportunity for developing other perovskite catalysts via NH_(3) plasma treatment.
基金supported by the National Natural Science Foundation of China(Nos.U22A20432,22278364,22211530045,22178308)the Fundamental Research Funds for the Central Universities(Nos.226-2022-00044,226-2022-00055)+6 种基金the Research Funds of Institute of Zhejiang University-Quzhou(No.IZQ2021KJ2003)National Key Research and Development Program of China(No.2022YFB4002100)the development project of Zhejiang Province's"Jianbing"and"Lingyan"(No.2023C01226)the Startup Foundation for Hundred-Talent Program of Zhejiang Universitythe Science Foundation of Donghai Laboratory(No.DH_(2)022ZY0009)Zhejiang University Global Partnership Fundthe China Postdoctoral Science Foundation(No.2021M702813)。
文摘Recently electrochemical synthesis of H_(2)O_(2)through oxygen reduction reaction(ORR)via 2e^(-)pathway is considered as a green and on-site route.However,it still remains a big challenge for fabricating novel metal-free catalysts under acidic solutions,since it suffers from high overpotential due to the intrinsically week*OOH adsorption.Herein,a co-doped carbon nanosheet(O/N–C)catalyst toward regulating O and N content was synthesized for improving the selectivity and activity of H_(2)O_(2)electrosynthesis process.The O/N–C exhibits outstanding 2e-ORR performance with low onset potential of 0.4 V(vs.RHE)and a selectivity of 92.4%in 0.1 mol/L HClO_(4)solutions.The in situ electrochemical impedance spectroscopy(EIS)tests reveals that the N incorporation contributes to the fast ORR kinetics.The density functional theory(DFT)calculations demonstrate that the binding strength of*OOH was optimized by the co-doping of oxygen and nitrogen at certain content,and the O/N–C–COOH site exhibits a lower theoretical overpotential for H_(2)O_(2)formation than O–C–COOH site.Furthermore,the promoted kinetics for typical organic dye degradation in simultaneous electron-Fenton process on O/N–C catalyst was demonstrated particularly for broadening its environmental application.
基金Project(2022YFC3900804)supported by the National Key Research and Development Program,ChinaProjects(2021JJ10058,2022JJ10074)supported by the Natural Science Foundation of Hunan Province of China。
文摘Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-doped Ni-Co-Mn(N-NCM)electrocatalyst from waste LIBs,for robust oxygen evolution application.Lithium-rich solution and NCM oxides are effectively separated from ternary cathode materials by sulfation roasting and low-temperature water leaching approach,in which the recovery efficiency of Li metal reaches nearly 100%.By facile NH_(3)treatment,the incorporation of N into NCM significantly increases the ratio of low-valence state Co^(2+)and Mn^(2+),and the formed Mn-N bond benefits the surface catalytic kinetics.Meanwhile,the N doping induces lattice expansion of the NCM,triggering tensile stress to favor the adsorption of the reactant.Thus,the optimized N-NCM electrocatalyst exhibits the superior overpotentials of 256 and 453 mV to achieve the current density of 10 and 100 mA/cm^(2),respectively,with a low Tafel slope of 37.3 mV/dec.This work provides a fresh avenue for recycling spent LIBs in the future to achieve sustainable development.
基金supported by the Natural Science Foundation of China(No.11079005 and 21033009)the Ministry of Science and Technology of China(2011CBA00503 and 2012CB720302)
文摘Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vital to explore alternative catalysts without mercury. We report here that N-doped carbon can catalyze directly transformation of acetylene to vinyl chloride. Particularly, N-doped high surface area mesoporous carbon exhibits a rather high activity with the acetylene conversion reaching 77% and vinyl chloride selectivity above 98% at a space velocity of 1.0 mL.min-l.g-1 and 200 ~C. It delivers a stable performa℃nce within a test period of 100h and no obvious deactivation is observed, demonstrating potentials to substitute the notoriously toxic mercuric chloride catalyst.
基金Zhejiang Provincial Natural Science Foundation of China(LY17B030010)~~
文摘We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent catalytic performance in acetylene hydrochlorination.Herein,we examined the activity of Au supported on N‐MC(Au/N‐MC)and compared it with that of Au supported on nitrogen‐free mesoporous carbon(Au/MC).The acetylene conversion of Au/N‐MC was 50%at 180°C with an acetylene space velocity of 600 h–1 and VHCl/VC2H2 of 1.1,which was double the activity of Au/MC(25%).The introduced nitrogen atoms acted as anchor sites that stabilized the Au3+species and inhibited the reduction of Au3+to Au0 during the preparation of Au/N‐MC catalysts.
基金the National Natural Science Foundation of China(Nos.51874110 and 51604089)the Natural Science Foundation of Heilongjiang Province(No.YQ2021B004)the Open Project of State Key Laboratory of Urban Water Resource and Environment(No.QA202138)。
文摘The discontinuity of new types of clean energy,such as wind power and solar cells, has promoted the development of large-scale energy storage systems(EES).Rechargeable aqueous zinc-ion batteries(ZIBs) have received extensive attention due to their inherent safety and low cost. At this stage, the performance of ZIBs is still limited by cathode materials. In this work, we have constructed a ZIBs cathode material-V_(2)O_(3)@N–C, through surface coating and N atom doping. The N-doped carbon coating endows V_(2)O_(3)@N–C with excellent structural stability and enhances its electrical conductivity. As a result,V_(2)O_(3)@N–C cathode delivers exceptional reversible of Zn^(2+) intercalation/deintercalation. The fabricated Zn/V_(2)O_(3)@N–C batteries exhibit high capacity of 274.6 mAh·g^(-1) at 5 A·g^(-1) and excellent capacity retention of 94% after 2000 cycles. The reversible intercalation/deintercalation of Zn^(2+) in the V_(2)O_(3)@N–C cathode is proved by ex-situ testing methods. It is believed that this work should inject new vitality into the development of ZIBs cathode.
