Zinc-ion hybrid supercapacitors(ZHSCs)have enormous potential for future applications in electric vehi-cles,portable/wearable electronic gadgets,etc.However,to accelerate ZHSC technology towards market applications,it...Zinc-ion hybrid supercapacitors(ZHSCs)have enormous potential for future applications in electric vehi-cles,portable/wearable electronic gadgets,etc.However,to accelerate ZHSC technology towards market applications,it is necessary to overcome research challenges such as Zn dendrites,low Zn utilization,and all-climate adaptability,as well as to streamline the device assembly process.In this study,we propose a new strategy for the facile construction of ZHSC via two porous carbon fabrics and a Zn plating solution.The cathode and current collector of the device are both porous graphitized carbon fabric(PGCF)pre-pared by high-temperature activation of K2 FeO_(4),and the Li_(2)ZnCl_(4)·9H_(2)O electrolyte is verified to possess excellent Zn plating/stripping efficiency and inhibition of Zn dendrite growth in a Zn-Zn symmetric cell model.As a result,the assembled ZHSC has the maximum energy density of 2.02 mWh cm^(−2)and the highest power density of 11.47 mW cm^(−2),and it can operate for 30,000 cycles without capacity degrada-tion.Furthermore,the destruction of the hydrogen bonding network by the high concentration of Cl−at low temperatures endows it with low freezing point properties and excellent ionic activity at low tem-peratures.The device also operated reliably at-60℃,with a maximum areal capacity of 1.15 mAh cm^(−2).This research offers new findings and insights for the development of high-performance ultra-cryogenic ZHSC devices.展开更多
Graphitized spent carbon cathode(SCC)is a hazardous solid waste generated in the aluminum electrolysis process.In this study,a flotation-acid leaching process is proposed for the purification of graphitized SCC,and th...Graphitized spent carbon cathode(SCC)is a hazardous solid waste generated in the aluminum electrolysis process.In this study,a flotation-acid leaching process is proposed for the purification of graphitized SCC,and the use of the purified SCC as an anode material for lithium-ion batteries is explored.The flotation and acid leaching processes were separately optimized through one-way experiments.The maximum SCC carbon content(93wt%)was achieved at a 90%proportion of−200-mesh flotation particle size,a slurry concentration of 10wt%,a rotation speed of 1600 r/min,and an inflatable capacity of 0.2 m^(3)/h(referred to as FSCC).In the subsequent acid leaching process,the SCC carbon content reached 99.58wt%at a leaching concentration of 5 mol/L,a leaching time of 100 min,a leaching temperature of 85°C,and an HCl/FSCC volume ratio of 5:1.The purified graphitized SCC(referred to as FSCC-CL)was utilized as an anode material,and it exhibited an initial capacity of 348.2 mAh/g at 0.1 C and a reversible capacity of 347.8 mAh/g after 100 cycles.Moreover,compared with commercial graphite,FSCC-CL exhibited better reversibility and cycle stability.Thus,purified SCC is an important candidate for anode material,and the flotation-acid leaching purification method is suitable for the resourceful recycling of SCC.展开更多
Potassium-ion batteries(KIBs)have great potential for applications in large-scale energy storage devices.However,the larger radius of K+leads to sluggish kinetics and inferior cycling performance,severely restricting ...Potassium-ion batteries(KIBs)have great potential for applications in large-scale energy storage devices.However,the larger radius of K+leads to sluggish kinetics and inferior cycling performance,severely restricting its practical applicability.Herein,we propose a rational strategy involving a Prussian blue analogue-derived graphitized carbon anode with fast and durable potassium storage capability,which is constructed by encapsulating cobalt nanoparticles in nitrogen-doped graphitized carbon(Co-NC).Both experimental and theoretical results show that N-doping effectively promotes the uniform dispersion of cobalt nanoparticles in the carbon matrix through Co-N bonds.Moreover,the cobalt nanoparticles and strong Co-N bonds synergistically form a threedimensional conductive network,increase the number of adsorption sites,and reduce the diffusion energy barrier,thereby facilitating the adsorption and the diffusion kinetics.These multiple effects lead to enhanced reversible capacities of 305 and 208.6 mAh g^−1 after 100 and 300 cycles at 0.05 and 0.1 A g^−1,respectively,demonstrating the applicability of the Co-NC anode for KIBs.展开更多
Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as p...Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as precursor,a novel noble-metal-free FeCo@NGC cocatalyst(nano-FeCo alloy@N-doped graphitized carbon) is fabricated by a simple pyrolysis method.Coupling with g-C3 N4, the optimal FeCo@NGC/g-C3N4 receives a boosted visible light driven photocatalytic H2 evolution rate of 42.2 μmol h-1, which is even higher than that of 1.0 wt% Pt modified g-C3N4 photocatalyst.Based on the results of density functional theory(DFT) calculations and practical experiment measurements,such outstanding photocatalytic performance of FeCo@NGC/g-C3N4 is mainly attributed to two aspects.One is the accelerated charge transfer behavior,induced by a photogene rated electrons secondary transfer performance on the surface of FeCo alloy nanoparticles.The other is related to the adjustment of H adsorption energy(approaching the standard hydrogen electrode potential) by the presence of external NGC thin layer.Both factors play key roles in the H2 evolution reaction.Such outstanding performance highlights an enormous potential of developing noble-metal-free bimetallic nano-alloy as inexpensive and efficient cocatalysts for solar applications.展开更多
Exploring nonprecious electrocatalysts for water splitting with high efficiency and durability is critically important.Herein,bimetallic phosphides are encapsulated into graphitized carbon to construct a C@NiCoP compo...Exploring nonprecious electrocatalysts for water splitting with high efficiency and durability is critically important.Herein,bimetallic phosphides are encapsulated into graphitized carbon to construct a C@NiCoP composite nanoarray using bimetallic metal-organic framework(MOF) as a self-sacrificial template.The resulting C@NiCoP exhibits superior performance for pH-universal electrocatalytic hydrogen evolution reaction(HER),particularly representing a low overpotential of 46.3 mV at 10 mA cm^(-2) and Tafel slope of 44.1 mV dec^(-1) in alkaline media.The structural characterizations combined with theoretical calculation demonstrate that tailored electronic structure from bimetal atoms and the synergistic effect with graphitized carbon layer could jointly optimize the adsorption ability of hydrogen on active sites in HER process,and enhance the electrical conductivity as well.In addition,the carbon layer served as a protecting shell also prevents highly dispersed NiCoP components from agglomeration and/or loss in harsh media,finally improving the durability.This work thus provides a new insight into optimizing activity and stability of pH-universal electrocatalysts by the nanostructural design and electronic structure modulation.展开更多
A novel chromatography stationary phase with a quasi-graphitized carbon modified shell has been developed. Coal pitch was directly carbonized on the surface of porous silica with in-situ carbonization. The carbonized ...A novel chromatography stationary phase with a quasi-graphitized carbon modified shell has been developed. Coal pitch was directly carbonized on the surface of porous silica with in-situ carbonization. The carbonized coal pitch coating exhibits some degree of graphitization with a 78 nm-thick layer on the surface of silica and a 0.5 nm-thick layer on the inner surface of the mesopores. Based on the special structure of the graphitized carbon coating, the novel stationary phase can provide multiple interactions such as hydrophobic interaction, π-π interaction and dipole-dipole interaction. The novel composite material exhibited unique separation selectivity and excellent separation efficiency for polar compounds, including imidazoles, nucleosides and pesticides. Besides, the packed column also exhibited great repeatability with the RSDs of the retention time of nucleosides between 0.07%-0.50%(n = 5). Finally, satisfied result was achieved in the separation of fullerenes on the new column, suggesting the great potential in the industrial-scale purification of fullerenes.展开更多
A needle coke was graphitized at different heat treatment temperature (2 000℃ to 3 000℃). The electrochemical intercalation mechanism of Li into the graphitized coke has been studied in Li|1 mol·L 1 LiClO 4+eth...A needle coke was graphitized at different heat treatment temperature (2 000℃ to 3 000℃). The electrochemical intercalation mechanism of Li into the graphitized coke has been studied in Li|1 mol·L 1 LiClO 4+ethylene carbonate/diethylene carbonate|graphite cells, using an in situ X Ray diffraction (XRD) technique.The study of Li C intercalation processes of the graphitized coke reveals that there are three major types of intercalation behavior.The first is uniformly intercalated at all Li C compounds in graphitized coke heated at 2 250℃;the second is obviously staging phenomenon during intercalation for the graphitized coke heated at 2 750℃; the third is cointercalation of solvated Li ion at high potential (>0.3V) and then lithium electrochemical intercalation at lower potential for that heated at 3 000℃, resulting in the decrease of capacity and efficiency of graphite negative electrode for lithium ion secondary battery.展开更多
Results of calculation of the power indicators of the ore restoration arc furnaces with the set power of 10.5 MVA workingon are given as on the self-baking also on the graphitized electrodes. It is established that de...Results of calculation of the power indicators of the ore restoration arc furnaces with the set power of 10.5 MVA workingon are given as on the self-baking also on the graphitized electrodes. It is established that despite high cost of the graphitizedelectrodes in comparison with the self-baking electrodes, power parameters much more improve. Besides, the natural power factorincreases, melting time decreases and that the most important the furnace turns out compact, convenient for service, building of thegraphitized electrodes is carried out for a small period, and also the number of service personnel is reduced. We propose a newdesign scheme of low-voltage circuit for the arc furnace according to the scheme ＂a triangle on the electrodes＂ designed in athree-bifilar version, in which more complete symmetry is gained by means of the crosspieces forming a triangle directly at theelectrode arms. In the proposed scheme, the current-carrying tubes that have different polarity are located on the same arm that leadsto further reduction in low-voltage circuit inductance. The application of this scheme allows for reducing reactive and activeresistances of low-voltage circuits by 2.5-3 times and 15-20%, respectively, as well as for shortening the heat, reducing specificenergy consumption and increasing the installation power factor.展开更多
The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially...The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially,the output of energy density for lithium ion batteries(LIBs)is directly affected by the delithiation capacity below 0.5 V.Here,the mildly expanded graphitized needle coke(MEGNC)with the enlarged interlayer spacing from 0.346 to 0.352 nm is obtained by the two-step mild oxidation intercalation modification.The voltage plateau of MEGNC anode below 0.5 V is obviously broadened as compared to the initial GNC anode,contributing to the enhancement of Li storage below the low voltage plateau.Moreover,the coin full cell and pouch full cell configured with MEGNC anode exhibit much enhanced Li storage ability,energy density and better cycling stability than those full cells configured with GNC and commercial graphite anodes,demonstrating the practical application value of MEGNC.The superior anode behaviors of MEGNC including the increased effective capacity at low voltage and superior cyclic stability are mainly benefited from the enlarged interlayer spacing,which not only accelerates the Li ions diffusion rate,but also effectively alleviates the volume expansion and fragmentation during the Li ions intercalation process.In addition,the above result is further confirmed by the density functional theory simulation.This work provides an effective modification strategy for the NC-based graphite to enhance the delithiation capacity at a low voltage plateau,dedicated to improving the energy density and durability of LIBs.展开更多
Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electro...Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electrolyte.Despite the low-cost expanded graphite-triethylaminehydrochloride(EG-ET)system has been improved in cycle performance,its rate capability still remains a gap with the expensive graphene-alkylimidazoliumchloride AIB system.In this work,we treated the cheap EG appropriately through an industrial high-temperature process,employed the obtained EG3K(treated at 3000℃)cathode with AlCl_(3)-ET electrolyte,and built a novel,high-rate capability and double-cheap AIB system.The new EG3K-ET system achieved the cathode capacity of average 110 m Ah g^(-1)at 1 A g^(-1)with 18,000cycles,and retained the cathode capacity of 100 m Ah g^(-1)at 5 A g^(-1)with 27,500 cycles(fast charging of 72 s).Impressively,we demonstrated that a battery pack(EG3K-ET system,12 m Ah)had successfully driven the Model car running 100 m long.In addition,it was confirmed that the improvement of rate capability in the EG3K-ET system was mainly derived by deposition,and its capacity contribution ratio was about 53.7%.This work further promoted the application potential of the low-cost EG-ET AIB system.展开更多
Graphitized nanocarbon materials can be an ideal catalyst support for heterogeneous catalytic systems. Their unique physical and chemical properties, such as large surface area, high adsorption capacity, excellent the...Graphitized nanocarbon materials can be an ideal catalyst support for heterogeneous catalytic systems. Their unique physical and chemical properties, such as large surface area, high adsorption capacity, excellent thermal and mechanical stability, outstanding electronic properties, and tunable porosity, allow the anchoring and dispersion of the active metals. Therefore, currently they are used as the key support material in many catalytic processes. This review summarizes recent relevant applications in supported catalysts that use graphitized nanocarbon as supports for catalytic oxidation, hydrogenation, dehydrogenation, and C-C coupling reactions in liquid-phase and gas-solid phase-reaction systems. The latest developments in specific features derived from the morphology and characteristics of graphitized na- nocarbon-supported metal catalysts are highlighted, as well as the differences in the catalytic behavior of graphitized nano- carbon-supported metal catalysts versus other related cata- lysts. The scientific challenges and opportunities in this field are also discussed.展开更多
We adopted the solution impregnation route with aluminum dihydrogen phosphate solution as liquid medium for effective surface modification on graphite substrate.The mass ratio of graphite to Al(H_(2)PO_(4))_(3) change...We adopted the solution impregnation route with aluminum dihydrogen phosphate solution as liquid medium for effective surface modification on graphite substrate.The mass ratio of graphite to Al(H_(2)PO_(4))_(3) changed from 0.5:1 to 4:1,and the impregnation time changed from 1 to 7 h.The typical composite phase change thermal storage materials doped with the as-treated graphite were fabricated using form-stable technique.To investigate the oxidation and anti-oxidation behavior of the impregnated graphite at high temperatures,the samples were put into a muffle furnace for a cyclic heat test.Based on SEM,EDS,DSC techniques,analyses on the impregnated technique suggested an optimized processing conditions of a 3 h impregnation time with the ratio of graphite:Al(H_(2)PO_(4))_(3) as 1:3 for graphite impregnation treatment.Further investigations on high-temperature phase change heat storage materials doped by the treated graphite suggested excellent oxidation resistance and thermal cycling performance.展开更多
Graphitic carbon nitride(g-C_(3)N_(4))exhibits great mechanical as well as thermal characteristics,making it a valuable ma-terial for use in photoelectric conversion devices,an accelerator for synthesis of organic com...Graphitic carbon nitride(g-C_(3)N_(4))exhibits great mechanical as well as thermal characteristics,making it a valuable ma-terial for use in photoelectric conversion devices,an accelerator for synthesis of organic compounds,an electrolyte for fuel cell applications or power sources,and a hydrogen storage substance and a fluorescence detector.It is fabricated using dif-ferent methods,and there is a variety of morphologies and nanostructures such as zero to three dimensions that have been designed for different purposes.Ther e are many reports about g-C_(3)N_(4) in recent years,but a comprehensive review which covers nanostructure dimensions and their properties are missing.This review paper aims to give basic and comprehensive understanding of the photocatalytic and electrocatalytic usages of g-C_(3)N_(4).It highlights the recent progress of g-C_(3)N_(4) nano-structure designing by covering synthesis methods,dimensions,morphologies,applications and properties.Along with the summary,we will also discuss the challenges and prospects.Scientists,investigators,and engineers looking at g-C_(3)N_(4) nanostructures for a variety of applications might find our review paper to be a useful resource.展开更多
Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience e...Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.展开更多
As an emerging electrochemical energy storage technology,potassium-ion batteries(PIBs),which are considered a“beyond Li-ion”battery system,have attracted tremendous attention due to their potential for providing a h...As an emerging electrochemical energy storage technology,potassium-ion batteries(PIBs),which are considered a“beyond Li-ion”battery system,have attracted tremendous attention due to their potential for providing a high energy density,and having abundant resource,and a low cost.However,their commercialization is hindered by the lack of practical anode materials.Among various reported anodes,conventional carbon materials,including graphite,soft carbon,and hard carbon,have emerged as promising candidates because of their abundance,low cost,high conductivity,and tunable structures.However,these materials have problems such as a low initial Coulombic efficiency,significant volume expansion,and unsatisfactory cyclability and rate performance.Various strategies to solve these have been explored,including optimizing the interlayer spacing,structural design,surface coating,constructing a multifunctional framework,and forming composites.This review provides a comprehensive overview of the recent progress in conventional carbon anodes,highlighting structural design strategies,mechanisms for improving the electrochemical performance,and underscores the critical role of these materials in promoting the practical application of PIBs.展开更多
Iron(Fe)nanoparticles and graphite(Gr)with different masses of bismuth trisulfide(Bi_(2)S_(3))were mixed by high-energy ball milling treatment to fabricate the corresponding composite iron anodes Bi_(2)S_(3)@Fe-Gr.The...Iron(Fe)nanoparticles and graphite(Gr)with different masses of bismuth trisulfide(Bi_(2)S_(3))were mixed by high-energy ball milling treatment to fabricate the corresponding composite iron anodes Bi_(2)S_(3)@Fe-Gr.The hydrogen evolution reaction and iron passivation process on these iron electrodes were investigated in alkaline and neutral solutions.The iron electrode Bi_(2)S_(3)-3@Fe-Gr(The additional amount of Bi_(2)S_(3)was 3 mg)revealed the strongest ability to inhibit hydrogen evolution among the iron electrodes of the present investigation,while the Bi_(2)S_(3)-6@Fe-Gr electrode(The additional amount of Bi_(2)S_(3)was 6 mg)delivered significant performance in inhibiting anodic passivation.This is because the high-energy ball milling process leads to the well-dispersion of Bi_(2)S_(3)and the changes in the surface of Fe nanoparticles,thereby slowing down the passivation of the iron electrode surface.展开更多
Magnesium potassium phosphate cement(MKPC)coatings exhibit potential for carbon steel protection but face challenges in practical application due to the preparation process and properties.This study develops flake gra...Magnesium potassium phosphate cement(MKPC)coatings exhibit potential for carbon steel protection but face challenges in practical application due to the preparation process and properties.This study develops flake graphite(FG)-modified MKPC coatings via spraying process,investigating the effects of FG size and dosage on phase composition,microstructure,mechanical properties,corrosion protection,and thermal conductivity.Results show that a low FG dosage(5 wt%)synergistically optimizes multifunctional performance.Compared to unmodified MKPC,FG2-1 exhibited exceptional impact resistance,associated with a 57%reduction in corrosion current density(icorr),a 356.3% increase in low-frequency impedance modulus(Z_(0.01 Hz))and a 37% increase in thermal conductivity.However,the coating with a high FG dosage(15 wt%)degraded performance due to defect accumulation and reduced crystallinity of KMgPO_(4)·6H_(2)O.This work advances the rational design of multifunctional inorganic coatings for extreme service environments requiring coupled corrosion protection and thermal management.展开更多
High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production meth...High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production method relies on repeated impregnation-carbonization and graphitization,and is plagued by lengthy preparation cycles and high energy consumption.Phase transition-assisted self-pressurized selfsintering technology can rapidly produce high-strength graphite materials,but the fracture strain of the graphite materials produced is poor.To solve this problem,this study used a two-step sintering method to uniformly introduce micro-nano pores into natural graphite-based bulk graphite,achieving improved fracture strain of the samples without reducing their density and mechanical properties.Using natural graphite powder,micron-diamond,and nano-diamond as raw materials,and by precisely controlling the staged pressure release process,the degree of diamond phase transition expansion was effectively regulated.The strain-to-failure of the graphite samples reached 1.2%,a 35%increase compared to samples produced by fullpressure sintering.Meanwhile,their flexural strength exceeded 110 MPa,and their density was over 1.9 g/cm^(3).The process therefore produced both a high strength and a high fracture strain.The interface evolution and toughening mechanism during the two-step sintering process were investigated.It is believed that the micro-nano pores formed have two roles:as stress concentrators they induce yielding by shear and as multi-crack propagation paths they significantly lengthen the crack propagation path.The two-step sintering phase transition strategy introduces pores and provides a new approach for increasing the fracture strain of brittle materials.展开更多
CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed gra...CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed graphite-CeO_(2) interfaces to enhance solar-driven photothermal catalytic DRM.Compared with carbon nanotubes-modified CeO_(2)(CeO_(2)-CNT),graphite-modified CeO_(2)(CeO_(2)-GRA)constructed graphite-CeO_(2) interfaces with distortion in CeO_(2),leading to the formation abundant oxygen vacancies.These graphite-CeO_(2) interfaces with oxygen vacancies enhanced optical absorption and promoted the generation and separation of photogenerated carriers.The high endothermic capacity of graphite elevated the catalyst surface temperature from 592.1−691.3℃,boosting light-to-thermal conversion.The synergy between photogenerated carriers and localized heat enabled Ni/CeO_(2)-GRA to achieve a CO production rate of 9985.6 mmol/(g·h)(vs 7192.4 mmol/(g·h)for Ni/CeO_(2))and a light-to-fuel efficiency of 21.8%(vs 13.8%for Ni/CeO_(2)).This work provides insights for designing graphite-semiconductor interfaces to advance photothermal catalytic efficiency.展开更多
基金supported by the National Natural Science Foun-dation of China(Grant No.51902041).
文摘Zinc-ion hybrid supercapacitors(ZHSCs)have enormous potential for future applications in electric vehi-cles,portable/wearable electronic gadgets,etc.However,to accelerate ZHSC technology towards market applications,it is necessary to overcome research challenges such as Zn dendrites,low Zn utilization,and all-climate adaptability,as well as to streamline the device assembly process.In this study,we propose a new strategy for the facile construction of ZHSC via two porous carbon fabrics and a Zn plating solution.The cathode and current collector of the device are both porous graphitized carbon fabric(PGCF)pre-pared by high-temperature activation of K2 FeO_(4),and the Li_(2)ZnCl_(4)·9H_(2)O electrolyte is verified to possess excellent Zn plating/stripping efficiency and inhibition of Zn dendrite growth in a Zn-Zn symmetric cell model.As a result,the assembled ZHSC has the maximum energy density of 2.02 mWh cm^(−2)and the highest power density of 11.47 mW cm^(−2),and it can operate for 30,000 cycles without capacity degrada-tion.Furthermore,the destruction of the hydrogen bonding network by the high concentration of Cl−at low temperatures endows it with low freezing point properties and excellent ionic activity at low tem-peratures.The device also operated reliably at-60℃,with a maximum areal capacity of 1.15 mAh cm^(−2).This research offers new findings and insights for the development of high-performance ultra-cryogenic ZHSC devices.
基金supported by the National Natural Science Foundation of China(No.52274346).
文摘Graphitized spent carbon cathode(SCC)is a hazardous solid waste generated in the aluminum electrolysis process.In this study,a flotation-acid leaching process is proposed for the purification of graphitized SCC,and the use of the purified SCC as an anode material for lithium-ion batteries is explored.The flotation and acid leaching processes were separately optimized through one-way experiments.The maximum SCC carbon content(93wt%)was achieved at a 90%proportion of−200-mesh flotation particle size,a slurry concentration of 10wt%,a rotation speed of 1600 r/min,and an inflatable capacity of 0.2 m^(3)/h(referred to as FSCC).In the subsequent acid leaching process,the SCC carbon content reached 99.58wt%at a leaching concentration of 5 mol/L,a leaching time of 100 min,a leaching temperature of 85°C,and an HCl/FSCC volume ratio of 5:1.The purified graphitized SCC(referred to as FSCC-CL)was utilized as an anode material,and it exhibited an initial capacity of 348.2 mAh/g at 0.1 C and a reversible capacity of 347.8 mAh/g after 100 cycles.Moreover,compared with commercial graphite,FSCC-CL exhibited better reversibility and cycle stability.Thus,purified SCC is an important candidate for anode material,and the flotation-acid leaching purification method is suitable for the resourceful recycling of SCC.
基金supported by National Natural Science Foundation of China(Grant No.51932011,51802356)Innovation-Driven Project of Central South University(No.2020CX024)+3 种基金the Research Support Fund of the Collaborative Innovation Center of Manganese-Zinc-Vanadium Industrial Technology in Hunan Province(No.201809)the Program of Youth Talent Support for Hunan Province(2018RS3098)Hunan Provincial Innovation Foundation for Postgraduate(Grant No.CX2017B045)the Fundamental Research Funds for the Central Universities of Central South University(Grant No.2020zzts075).
文摘Potassium-ion batteries(KIBs)have great potential for applications in large-scale energy storage devices.However,the larger radius of K+leads to sluggish kinetics and inferior cycling performance,severely restricting its practical applicability.Herein,we propose a rational strategy involving a Prussian blue analogue-derived graphitized carbon anode with fast and durable potassium storage capability,which is constructed by encapsulating cobalt nanoparticles in nitrogen-doped graphitized carbon(Co-NC).Both experimental and theoretical results show that N-doping effectively promotes the uniform dispersion of cobalt nanoparticles in the carbon matrix through Co-N bonds.Moreover,the cobalt nanoparticles and strong Co-N bonds synergistically form a threedimensional conductive network,increase the number of adsorption sites,and reduce the diffusion energy barrier,thereby facilitating the adsorption and the diffusion kinetics.These multiple effects lead to enhanced reversible capacities of 305 and 208.6 mAh g^−1 after 100 and 300 cycles at 0.05 and 0.1 A g^−1,respectively,demonstrating the applicability of the Co-NC anode for KIBs.
基金supported by the National Natural Science Foundation of China (21972048, 21802046)the Natural Science Foundation of Guangdong Province (Nos. 2019A1515011138, 2017A030313090, 2017A030310086, 2018A0303130018)。
文摘Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as precursor,a novel noble-metal-free FeCo@NGC cocatalyst(nano-FeCo alloy@N-doped graphitized carbon) is fabricated by a simple pyrolysis method.Coupling with g-C3 N4, the optimal FeCo@NGC/g-C3N4 receives a boosted visible light driven photocatalytic H2 evolution rate of 42.2 μmol h-1, which is even higher than that of 1.0 wt% Pt modified g-C3N4 photocatalyst.Based on the results of density functional theory(DFT) calculations and practical experiment measurements,such outstanding photocatalytic performance of FeCo@NGC/g-C3N4 is mainly attributed to two aspects.One is the accelerated charge transfer behavior,induced by a photogene rated electrons secondary transfer performance on the surface of FeCo alloy nanoparticles.The other is related to the adjustment of H adsorption energy(approaching the standard hydrogen electrode potential) by the presence of external NGC thin layer.Both factors play key roles in the H2 evolution reaction.Such outstanding performance highlights an enormous potential of developing noble-metal-free bimetallic nano-alloy as inexpensive and efficient cocatalysts for solar applications.
基金supported by the National Natural Science Foundation of China (nos. 21771012, 22038001, 51621003)。
文摘Exploring nonprecious electrocatalysts for water splitting with high efficiency and durability is critically important.Herein,bimetallic phosphides are encapsulated into graphitized carbon to construct a C@NiCoP composite nanoarray using bimetallic metal-organic framework(MOF) as a self-sacrificial template.The resulting C@NiCoP exhibits superior performance for pH-universal electrocatalytic hydrogen evolution reaction(HER),particularly representing a low overpotential of 46.3 mV at 10 mA cm^(-2) and Tafel slope of 44.1 mV dec^(-1) in alkaline media.The structural characterizations combined with theoretical calculation demonstrate that tailored electronic structure from bimetal atoms and the synergistic effect with graphitized carbon layer could jointly optimize the adsorption ability of hydrogen on active sites in HER process,and enhance the electrical conductivity as well.In addition,the carbon layer served as a protecting shell also prevents highly dispersed NiCoP components from agglomeration and/or loss in harsh media,finally improving the durability.This work thus provides a new insight into optimizing activity and stability of pH-universal electrocatalysts by the nanostructural design and electronic structure modulation.
基金supported by the National Natural Science Foundation of China (No. 21974045)the Science and Technology Commission of Shanghai Municipality (No. 19142201100)+1 种基金the Fundamental Research Funds for the Central Universities (No. JKJ01211718)the National Key R&D Program of China (No. 2021YFF0701900)。
文摘A novel chromatography stationary phase with a quasi-graphitized carbon modified shell has been developed. Coal pitch was directly carbonized on the surface of porous silica with in-situ carbonization. The carbonized coal pitch coating exhibits some degree of graphitization with a 78 nm-thick layer on the surface of silica and a 0.5 nm-thick layer on the inner surface of the mesopores. Based on the special structure of the graphitized carbon coating, the novel stationary phase can provide multiple interactions such as hydrophobic interaction, π-π interaction and dipole-dipole interaction. The novel composite material exhibited unique separation selectivity and excellent separation efficiency for polar compounds, including imidazoles, nucleosides and pesticides. Besides, the packed column also exhibited great repeatability with the RSDs of the retention time of nucleosides between 0.07%-0.50%(n = 5). Finally, satisfied result was achieved in the separation of fullerenes on the new column, suggesting the great potential in the industrial-scale purification of fullerenes.
文摘A needle coke was graphitized at different heat treatment temperature (2 000℃ to 3 000℃). The electrochemical intercalation mechanism of Li into the graphitized coke has been studied in Li|1 mol·L 1 LiClO 4+ethylene carbonate/diethylene carbonate|graphite cells, using an in situ X Ray diffraction (XRD) technique.The study of Li C intercalation processes of the graphitized coke reveals that there are three major types of intercalation behavior.The first is uniformly intercalated at all Li C compounds in graphitized coke heated at 2 250℃;the second is obviously staging phenomenon during intercalation for the graphitized coke heated at 2 750℃; the third is cointercalation of solvated Li ion at high potential (>0.3V) and then lithium electrochemical intercalation at lower potential for that heated at 3 000℃, resulting in the decrease of capacity and efficiency of graphite negative electrode for lithium ion secondary battery.
文摘Results of calculation of the power indicators of the ore restoration arc furnaces with the set power of 10.5 MVA workingon are given as on the self-baking also on the graphitized electrodes. It is established that despite high cost of the graphitizedelectrodes in comparison with the self-baking electrodes, power parameters much more improve. Besides, the natural power factorincreases, melting time decreases and that the most important the furnace turns out compact, convenient for service, building of thegraphitized electrodes is carried out for a small period, and also the number of service personnel is reduced. We propose a newdesign scheme of low-voltage circuit for the arc furnace according to the scheme ＂a triangle on the electrodes＂ designed in athree-bifilar version, in which more complete symmetry is gained by means of the crosspieces forming a triangle directly at theelectrode arms. In the proposed scheme, the current-carrying tubes that have different polarity are located on the same arm that leadsto further reduction in low-voltage circuit inductance. The application of this scheme allows for reducing reactive and activeresistances of low-voltage circuits by 2.5-3 times and 15-20%, respectively, as well as for shortening the heat, reducing specificenergy consumption and increasing the installation power factor.
基金supported by the National Natural Science Foundation of China(21776309,22122807 and 21706283)。
文摘The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially,the output of energy density for lithium ion batteries(LIBs)is directly affected by the delithiation capacity below 0.5 V.Here,the mildly expanded graphitized needle coke(MEGNC)with the enlarged interlayer spacing from 0.346 to 0.352 nm is obtained by the two-step mild oxidation intercalation modification.The voltage plateau of MEGNC anode below 0.5 V is obviously broadened as compared to the initial GNC anode,contributing to the enhancement of Li storage below the low voltage plateau.Moreover,the coin full cell and pouch full cell configured with MEGNC anode exhibit much enhanced Li storage ability,energy density and better cycling stability than those full cells configured with GNC and commercial graphite anodes,demonstrating the practical application value of MEGNC.The superior anode behaviors of MEGNC including the increased effective capacity at low voltage and superior cyclic stability are mainly benefited from the enlarged interlayer spacing,which not only accelerates the Li ions diffusion rate,but also effectively alleviates the volume expansion and fragmentation during the Li ions intercalation process.In addition,the above result is further confirmed by the density functional theory simulation.This work provides an effective modification strategy for the NC-based graphite to enhance the delithiation capacity at a low voltage plateau,dedicated to improving the energy density and durability of LIBs.
基金the support of the National Natural Science Foundation of China(51533008,51703194 and 21805242)the National Key R&D Program of China(2016YFA0200200)the Excellent Postdoctoral Special Fund of Zhejiang University for funding this research work。
文摘Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electrolyte.Despite the low-cost expanded graphite-triethylaminehydrochloride(EG-ET)system has been improved in cycle performance,its rate capability still remains a gap with the expensive graphene-alkylimidazoliumchloride AIB system.In this work,we treated the cheap EG appropriately through an industrial high-temperature process,employed the obtained EG3K(treated at 3000℃)cathode with AlCl_(3)-ET electrolyte,and built a novel,high-rate capability and double-cheap AIB system.The new EG3K-ET system achieved the cathode capacity of average 110 m Ah g^(-1)at 1 A g^(-1)with 18,000cycles,and retained the cathode capacity of 100 m Ah g^(-1)at 5 A g^(-1)with 27,500 cycles(fast charging of 72 s).Impressively,we demonstrated that a battery pack(EG3K-ET system,12 m Ah)had successfully driven the Model car running 100 m long.In addition,it was confirmed that the improvement of rate capability in the EG3K-ET system was mainly derived by deposition,and its capacity contribution ratio was about 53.7%.This work further promoted the application potential of the low-cost EG-ET AIB system.
基金supported by the Ministry of Science and Technology (2016YFA0204100)the National Natural Science Foundation of China (21573254 and 91545110)+1 种基金the Youth Innovation Promotion Association (CAS)the Sinopec China and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09030103)
文摘Graphitized nanocarbon materials can be an ideal catalyst support for heterogeneous catalytic systems. Their unique physical and chemical properties, such as large surface area, high adsorption capacity, excellent thermal and mechanical stability, outstanding electronic properties, and tunable porosity, allow the anchoring and dispersion of the active metals. Therefore, currently they are used as the key support material in many catalytic processes. This review summarizes recent relevant applications in supported catalysts that use graphitized nanocarbon as supports for catalytic oxidation, hydrogenation, dehydrogenation, and C-C coupling reactions in liquid-phase and gas-solid phase-reaction systems. The latest developments in specific features derived from the morphology and characteristics of graphitized na- nocarbon-supported metal catalysts are highlighted, as well as the differences in the catalytic behavior of graphitized nano- carbon-supported metal catalysts versus other related cata- lysts. The scientific challenges and opportunities in this field are also discussed.
基金Funded by Scientific and Technological Innovation Project of Carbon Emission Peak and Carbon Neutrality of Jiangsu Province(No.BE2022028-4)。
文摘We adopted the solution impregnation route with aluminum dihydrogen phosphate solution as liquid medium for effective surface modification on graphite substrate.The mass ratio of graphite to Al(H_(2)PO_(4))_(3) changed from 0.5:1 to 4:1,and the impregnation time changed from 1 to 7 h.The typical composite phase change thermal storage materials doped with the as-treated graphite were fabricated using form-stable technique.To investigate the oxidation and anti-oxidation behavior of the impregnated graphite at high temperatures,the samples were put into a muffle furnace for a cyclic heat test.Based on SEM,EDS,DSC techniques,analyses on the impregnated technique suggested an optimized processing conditions of a 3 h impregnation time with the ratio of graphite:Al(H_(2)PO_(4))_(3) as 1:3 for graphite impregnation treatment.Further investigations on high-temperature phase change heat storage materials doped by the treated graphite suggested excellent oxidation resistance and thermal cycling performance.
基金M Tahir is funded by EU H2020 Marie Skłodows-ka-Curie Fellowship(1439425).
文摘Graphitic carbon nitride(g-C_(3)N_(4))exhibits great mechanical as well as thermal characteristics,making it a valuable ma-terial for use in photoelectric conversion devices,an accelerator for synthesis of organic compounds,an electrolyte for fuel cell applications or power sources,and a hydrogen storage substance and a fluorescence detector.It is fabricated using dif-ferent methods,and there is a variety of morphologies and nanostructures such as zero to three dimensions that have been designed for different purposes.Ther e are many reports about g-C_(3)N_(4) in recent years,but a comprehensive review which covers nanostructure dimensions and their properties are missing.This review paper aims to give basic and comprehensive understanding of the photocatalytic and electrocatalytic usages of g-C_(3)N_(4).It highlights the recent progress of g-C_(3)N_(4) nano-structure designing by covering synthesis methods,dimensions,morphologies,applications and properties.Along with the summary,we will also discuss the challenges and prospects.Scientists,investigators,and engineers looking at g-C_(3)N_(4) nanostructures for a variety of applications might find our review paper to be a useful resource.
文摘Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.
文摘As an emerging electrochemical energy storage technology,potassium-ion batteries(PIBs),which are considered a“beyond Li-ion”battery system,have attracted tremendous attention due to their potential for providing a high energy density,and having abundant resource,and a low cost.However,their commercialization is hindered by the lack of practical anode materials.Among various reported anodes,conventional carbon materials,including graphite,soft carbon,and hard carbon,have emerged as promising candidates because of their abundance,low cost,high conductivity,and tunable structures.However,these materials have problems such as a low initial Coulombic efficiency,significant volume expansion,and unsatisfactory cyclability and rate performance.Various strategies to solve these have been explored,including optimizing the interlayer spacing,structural design,surface coating,constructing a multifunctional framework,and forming composites.This review provides a comprehensive overview of the recent progress in conventional carbon anodes,highlighting structural design strategies,mechanisms for improving the electrochemical performance,and underscores the critical role of these materials in promoting the practical application of PIBs.
文摘Iron(Fe)nanoparticles and graphite(Gr)with different masses of bismuth trisulfide(Bi_(2)S_(3))were mixed by high-energy ball milling treatment to fabricate the corresponding composite iron anodes Bi_(2)S_(3)@Fe-Gr.The hydrogen evolution reaction and iron passivation process on these iron electrodes were investigated in alkaline and neutral solutions.The iron electrode Bi_(2)S_(3)-3@Fe-Gr(The additional amount of Bi_(2)S_(3)was 3 mg)revealed the strongest ability to inhibit hydrogen evolution among the iron electrodes of the present investigation,while the Bi_(2)S_(3)-6@Fe-Gr electrode(The additional amount of Bi_(2)S_(3)was 6 mg)delivered significant performance in inhibiting anodic passivation.This is because the high-energy ball milling process leads to the well-dispersion of Bi_(2)S_(3)and the changes in the surface of Fe nanoparticles,thereby slowing down the passivation of the iron electrode surface.
基金National Key Research and Development Program of China(2024YFB3714804)National Natural Science Foundation of China(52171277)+1 种基金Baima Lake Laboratory Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(LBMHZ24E020001)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2022SZ-TD006).
文摘Magnesium potassium phosphate cement(MKPC)coatings exhibit potential for carbon steel protection but face challenges in practical application due to the preparation process and properties.This study develops flake graphite(FG)-modified MKPC coatings via spraying process,investigating the effects of FG size and dosage on phase composition,microstructure,mechanical properties,corrosion protection,and thermal conductivity.Results show that a low FG dosage(5 wt%)synergistically optimizes multifunctional performance.Compared to unmodified MKPC,FG2-1 exhibited exceptional impact resistance,associated with a 57%reduction in corrosion current density(icorr),a 356.3% increase in low-frequency impedance modulus(Z_(0.01 Hz))and a 37% increase in thermal conductivity.However,the coating with a high FG dosage(15 wt%)degraded performance due to defect accumulation and reduced crystallinity of KMgPO_(4)·6H_(2)O.This work advances the rational design of multifunctional inorganic coatings for extreme service environments requiring coupled corrosion protection and thermal management.
基金Natural Science Foundation of Shanghai(24ZR1400800)he Natural Science Foundation of China(U23A20685,52073058,91963204)+1 种基金the National Key R&D Program of China(2021YFB3701400)Shanghai Sailing Program(23YF1400200)。
文摘High-performance graphite materials have important roles in aerospace and nuclear reactor technologies because of their outstanding chemical stability and high-temperature performance.Their traditional production method relies on repeated impregnation-carbonization and graphitization,and is plagued by lengthy preparation cycles and high energy consumption.Phase transition-assisted self-pressurized selfsintering technology can rapidly produce high-strength graphite materials,but the fracture strain of the graphite materials produced is poor.To solve this problem,this study used a two-step sintering method to uniformly introduce micro-nano pores into natural graphite-based bulk graphite,achieving improved fracture strain of the samples without reducing their density and mechanical properties.Using natural graphite powder,micron-diamond,and nano-diamond as raw materials,and by precisely controlling the staged pressure release process,the degree of diamond phase transition expansion was effectively regulated.The strain-to-failure of the graphite samples reached 1.2%,a 35%increase compared to samples produced by fullpressure sintering.Meanwhile,their flexural strength exceeded 110 MPa,and their density was over 1.9 g/cm^(3).The process therefore produced both a high strength and a high fracture strain.The interface evolution and toughening mechanism during the two-step sintering process were investigated.It is believed that the micro-nano pores formed have two roles:as stress concentrators they induce yielding by shear and as multi-crack propagation paths they significantly lengthen the crack propagation path.The two-step sintering phase transition strategy introduces pores and provides a new approach for increasing the fracture strain of brittle materials.
文摘CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed graphite-CeO_(2) interfaces to enhance solar-driven photothermal catalytic DRM.Compared with carbon nanotubes-modified CeO_(2)(CeO_(2)-CNT),graphite-modified CeO_(2)(CeO_(2)-GRA)constructed graphite-CeO_(2) interfaces with distortion in CeO_(2),leading to the formation abundant oxygen vacancies.These graphite-CeO_(2) interfaces with oxygen vacancies enhanced optical absorption and promoted the generation and separation of photogenerated carriers.The high endothermic capacity of graphite elevated the catalyst surface temperature from 592.1−691.3℃,boosting light-to-thermal conversion.The synergy between photogenerated carriers and localized heat enabled Ni/CeO_(2)-GRA to achieve a CO production rate of 9985.6 mmol/(g·h)(vs 7192.4 mmol/(g·h)for Ni/CeO_(2))and a light-to-fuel efficiency of 21.8%(vs 13.8%for Ni/CeO_(2)).This work provides insights for designing graphite-semiconductor interfaces to advance photothermal catalytic efficiency.
