Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in ...Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.展开更多
The development of sustainable electrode materials for energy storage systems has become very important and porous carbons derived from biomass have become an important candidate because of their tunable pore structur...The development of sustainable electrode materials for energy storage systems has become very important and porous carbons derived from biomass have become an important candidate because of their tunable pore structure,environmental friendliness,and cost-effectiveness.Recent advances in controlling the pore structure of these carbons and its relationship between to is energy storage performance are discussed,emphasizing the critical role of a balanced distribution of micropores,mesopores and macropores in determining electrochemical behavior.Particular attention is given to how the intrinsic components of biomass precursors(lignin,cellulose,and hemicellulose)influence pore formation during carbonization.Carbonization and activation strategies to precisely control the pore structure are introduced.Finally,key challenges in the industrial production of these carbons are outlined,and future research directions are proposed.These include the establishment of a database of biomass intrinsic structures and machine learning-assisted pore structure engineering,aimed at providing guidance for the design of high-performance carbon materials for next-generation energy storage devices.展开更多
Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of ni...Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of nitrogen-containing hypercrosslinked fer-rocene polymer precursors(HCP-FCs).Subsequent carbonization of these precursors results in the production of iron-nitrogen-doped por-ous carbon absorbers(Fe-NPCs).The Fe-NPCs demonstrate a porous structure comprising aggregated nanotubes and nanospheres.The porosity of this structure can be modulated by adjusting the iron and nitrogen contents to optimize impedance matching.The uniform dis-tribution of Fe-N_(x)C,N dipoles,andα-Fe within the carbon matrix can be ensured by using hypercrosslinked ferrocenes in constructing porous carbon,providing the absorber with numerous polarization sites and a conductive network.The electromagnetic wave absorption performance of the specially designed Fe-NPC-M_(2)absorbers is satisfactory,revealing a minimum reflection loss of-55.3 dB at 2.5 mm and an effective absorption bandwidth of 6.00 GHz at 2.0 mm.By utilizing hypercrosslinked polymers(HCPs)as precursors,a novel method for developing highly efficient carbon-based absorbing agents is introduced in this research.展开更多
Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessf...Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessfully prepared by blending ZIF-8 particles with sodium alginate,forming hydrogel beads in the presence of divalent metal ions,and subsequently subjecting them to high-temperature pyrolysis.Various characterization techniques were employed to evaluate the properties of the prepared materials.The introduction of a carbon framework on ZIF-8-derived particles effectively enhanced the conductivity of the prepared materials.The SA/ZIF-8(1.0)-C sample heated at 800℃exhibited a specific capacitance of up to 208 F g^(-1)at a current density of 0.5 A g^(-1)and outstanding cyclic stability.Even after 10,000 charge and discharge cycles,its capacitance retention rate remained as high as 87.14%.The symmetric supercapacitor constructed with the composite demonstrated an excellent energy density of 14.58 Wh kg^(-1)at a power capacity of 403.85 W kg^(-1).The implementation of this study provides new ideas and inspiration for the development of high-performance supercapacitors.展开更多
Hierarchical porous carbon(HPC)materials exhibit superior performance profiles in various applications due to their well-developed multiscale interconnected pore structures.The synthesis of HPC from natural biomass pr...Hierarchical porous carbon(HPC)materials exhibit superior performance profiles in various applications due to their well-developed multiscale interconnected pore structures.The synthesis of HPC from natural biomass precursors instead of fossil fuel-based precursors has gained considerable attention in recent decades.Rice husk,a globally abundant agricultural waste,offers a sustainable and cost-effective precursor for HPC production.The structural components and inherent silica content of rice husk act as a natural self-template for forming hierarchical pore structures with superior characteristics.In this review,recent studies on preparing rice husk-based HPC are summarized,and synthesis techniques are evaluated.In addition,recent advancements in activation methods and the effect of silica templates are reviewed while comparing these with traditional activated carbon production methods.Potential future directions for research and development activities are also discussed.Rice husk is a highly promising candidate for producing high-performance HPC materials.展开更多
Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a sim...Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and fillers.In this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate MMMs.The dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting MMMs.Concurrently,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in MMMs.As a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH_(4) selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper bound.Additionally,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@ZnO.In summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials.展开更多
Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of opera...Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of operation.However,the low adsorption capacity of the reported adsorbents is still a challenge for wastewater treatment with highefficiency.Here,we developed a super adsorbent(SUA-1),which was a kind of porous carbon nanofibers derived from a composite of PAN-based electrospinning and ZIF-8(PAN/ZIF-8)via simple heat treatment process.The asprepared SUA showed an ultra-high adsorption capacity for adsorbing methyl blue(MB)at nearly three times its own weight,as high as 2998.18 mg/g.A series tests demonstrated that the pore-making effect of ZIF-8 during heat treatment process endowed high BET surface area and generated ZnO components as chemical adsorption center.Under the synergistic effect of bonding and non-bonding forces including ionic bond,electrostatic interaction,andπ-πinteraction,the adsorption capacity has been greatly improved.In view of promising efficiency,this work provides guidance and insights for the preparation of highly efficient adsorbents based on electrospinning derived porous carbon nanofibers.展开更多
With the development of electronics and portable devices,there is a significant drive to develop electrode materials for supercapacitors that are lightweight,economical,and provide high energy and power densities.Lign...With the development of electronics and portable devices,there is a significant drive to develop electrode materials for supercapacitors that are lightweight,economical,and provide high energy and power densities.Lignin-based porous carbons have recently been extensively studied for en-ergy storage applications because of their characteristics of large specific surface area,easy doping,and high conductivity.Significant progress in the synthesis of porous carbons derived from lignin,using different strategies for their preparation and modification with heteroatoms,metal oxides,met-al sulfides,and conductive polymers is considered and their electrochemical performances and ion storage mechanisms are discussed.Considerable fo-cus is directed towards the challenges encountered in using lignin-based por-ous carbons and the ways to optimize specific capacity and energy density for supercapacitor applications.Finally,the limitations of existing technolo-gies and research directions for improving the performance of lignin-based carbons are discussed.展开更多
The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous...The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous carbon nanosheets doped with both Fe and Ni(Fe/Ni-N-PCNSs)by an easy and template-free approach that solve this problem.Because of their ultrathin porous 2D structure and uniform distribution of Fe and Ni dopants,they capture polysulfides,speed up the sulfur redox reaction,and improve the material’s lithiophilicity,greatly suppressing the shuttling of polysulfides and dendrite growth on the lithium anode.As a result,it has an exceptional performance as a stable host for elemental sulfur and metallic lithium,producing a record long life of 1000 cycles with a very small capacity decay of 0.00025%per cycle in a Li-S battery and an excellent cycling stability of over 850 h with a small overpotential of>72 mV in a lithium metal battery.This work suggests the use of multifunctional-based 2D porous carbon nanosheets as a stable host for both elemental sulfur and metallic lithium to improve the Li-S battery per-formance.展开更多
Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as...Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.展开更多
The typical method for preparing the porous carbon used in supercapacitors(SCs)is time-consuming and energy-intensive.We report a fast and efficient route to synthesize and tailor the structure of porous carbon by a J...The typical method for preparing the porous carbon used in supercapacitors(SCs)is time-consuming and energy-intensive.We report a fast and efficient route to synthesize and tailor the structure of porous carbon by a Joule heating technique(JHT)using phenolic resin and precursors.During the JHT process,the time and energy needed are both significantly reduced because the precursor is heated to the target temperature at a rate of 1100 K/s,so the porous carbon is formed with the release of small molecules and the etching of the substrate by K_(2)CO_(3).JHT has a higher energy efficiency than traditional carbonization methods in a tube furnace and allows for precise control of the pyrolysis process,thus achieving better control of the material’s structure and properties.Samples obtained by JHT contain abundant pores and a large specific surface area(1652.7 m^(2)/g),which give an excellent specific capacitance of 476.0 F/g and rate capability(75.1%capacitance retention at 64.0 A/g in an aqueous alkaline electrolyte).Furthermore,in electrolytes of 17.0 mol/kg NaClO_(4)(water-in-salt)and 1.0 mol/L TEABF4/AN,the symmetric SCs have a maximum energy density of 33.3 and 50.8 Wh/kg at power densities of 220.4 and 376.4 W/kg,respectively.The cells also have good long-term stability,with a nearly 100%Coulombic efficiency,and a capacitance retention of 93.1%in a water-in-salt electrolyte after 10000 cycles,and 88.9%in an organic electrolyte after 8000 cycles.This study shows that JHT has the potential to serve as an ultra-fast method to prepare porous carbons for energy storage.展开更多
The search for novel carbons has been an important research topic for developing high-performance anodes of lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs).In this study,we fabricated a new carbon,long-range...The search for novel carbons has been an important research topic for developing high-performance anodes of lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs).In this study,we fabricated a new carbon,long-range ordered porous carbon(LOPC),by inducing covalent bonds between face-centered cubic C_(60)(fcc C_(60))cages in a molecular crystal via electron injection under vacuum at~520°C.The LOPC maintains the periodic lattice of the fcc C_(60)molecular crystal but has improved structural stability and electrical conductivity because of the sp^(2)bonding formed between C_(60)molecules.Compared with fcc C_(60),which has a much greater specific surface area(327.1 m^(2)·g^(−1)),LOPC has a specific capacity of 820.9 mA·h·g^(−1)or 292.9 mA·h·g^(−1)as an anode for LIBs or SIBs,both of which are measured at a current density of 0.1 A·g^(−1).This porous yet ordered carbon may open new opportunities for anode materials in electrochemical energy storage.展开更多
To optimize the CO_(2) adsorption performance of carbon materials,this study proposed a preparation method for biomass-based porous carbon through hydrothermal carbonization coupled with nitrogen source optimization a...To optimize the CO_(2) adsorption performance of carbon materials,this study proposed a preparation method for biomass-based porous carbon through hydrothermal carbonization coupled with nitrogen source optimization and K_(2)CO_(3) activation.The effects of different nitrogen sources(urea,piperazine,melamine,and polyaniline)and activation temperatures on the physicochemical features and CO_(2) adsorption characteristics of the porous carbons were systematically investigated.The results indicated that different nitrogen sources showed varying impacts on the CO_(2) uptake of porous carbons,and not all nitrogen sources enhanced the adsorption performance.The urea and piperazine doped porous carbons exhibited relatively low nitrogen contents and specific surface areas.Whereas the melamine doped carbons showed higher nitrogen contents and specific surface areas,but lacked narrow micropores,limiting their CO_(2) adsorption performance.In contrast,PAC-700,prepared using polyaniline as nitrogen source,featured a well-developed pore structure,abundant narrow micropores and pyrrolic-N groups,endowing it with enhanced CO_(2) adsorption capability.At 0℃/1 bar and 25℃/1 bar,the CO_(2) uptake of PAC-700 reached 6.85 and 4.64 mmol/g,respectively.Additionally,PAC-700 maintained a CO_(2) uptake retention ratio of 99%after 5 adsorption-desorption cycles and exhibited good CO_(2)/N_(2) selectivity of 22.4−51.6.These findings highlighted the advantageous CO_(2) adsorption performance of PAC-700,indicating its substantial application potential in the domain of carbon capture.展开更多
Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and exp...Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost.展开更多
The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and exper...The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.展开更多
Antimony(Sb)is regarded as a potential candidate for next-generation anode materials for rechargeable batteries because it has a high theoretical specific capacity,excellent conductivity and appropriate reaction poten...Antimony(Sb)is regarded as a potential candidate for next-generation anode materials for rechargeable batteries because it has a high theoretical specific capacity,excellent conductivity and appropriate reaction potential.However,Sb-based anodes suffer from severe volume expansion of>135%during the lithiation-delithiation process.Hence,we construct a novel Sb@C composite encapsulating the Sb nanoparticles into highly conductive three-dimensional porous carbon frameworks via the one-step magnesiothermic reduction(MR).The porous carbon provides buffer spaces to accommodate the volume expansion of Sb.Meanwhile,the three-dimensional(3D)interconnected carbon frameworks shorten the ion/electron transport pathway and inhibit the overgrowth of unstable solid-electrolyte interfaces(SEIs).Consequently,the 3D Sb@C composite displays remarkable electrochemical performance,including a high average Coulombic efficiency(CE)of>99%,high initial capability of 989 mAh·g^(-1),excellent cycling stability for over 1000 cycles at a high current density of 5 A·g^(-1).Furthermore,employing a similar approach,this 3D Sb@C design paradigm holds promise for broader applications across fast-charging and ultralong-life battery systems beyond Li+.This work aims to advance practical applications for Sb-based anodes in next-generation batteries.展开更多
Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Effi...Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Efficient potassium activation is the key to develop high-performance oxygen-rich porous carbon cathodes.Herein,the alkali lignin,extracted from eucalyptus wood by geopolymer-assisted low-alkali pretreatment,is used to prepare oxygen-rich lignin-derived porous carbons(OLPCs)through KOH activation and K_(2)CO_(3)activation at 700-900℃.KOH activation constructs a hierarchical micro-mesoporous structure,while K_(2)CO_(3)activation constructs a microporous structure.Furthermore,K_(2)CO_(3)activation could more efficiently construct active oxygen(C=O)species than KOH activation.The OLPCs prepared by KOH/K_(2)CO_(3)activations at 800℃show the highest microporosity(78.4/87.7%)and C=O content(5.3/8.0 at.%).Due to that C=O and micropore adsorb zinc ions,the OLPCs prepared by K_(2)CO_(3)activation at 800℃with higher C=O content and microporosity deliver superior capacitive performance(256 F g^(-1)at 0.1 A g^(-1))than that by KOH activation at 800℃(224 F g^(-1)at 0.1 A g^(-1)),and excellent cycling stability.This work provides a new insight into the sustainable preparation of oxygenrich porous carbon cathodes through efficient potassium activation for ZIHCs.展开更多
Low specific capacitances and/or limited working potential(≤4.5 V).of the prevalent carbon-based positive electrodes as the inborn bottleneck seriously hinder practical advancement of lithium-ion capacitors.Thus,brea...Low specific capacitances and/or limited working potential(≤4.5 V).of the prevalent carbon-based positive electrodes as the inborn bottleneck seriously hinder practical advancement of lithium-ion capacitors.Thus,breakthroughs in enhancement of both specific capacitances and upper cutoff potentials are enormously significant for high-energy density lithium-ion capacitors.Herein,we first meticulously design and scalably fabricate a commercializable fluorine-doped porous carbon material with competitive tap density,large active surface,appropriate aperture distribution,and promoted affinity with the electrolyte,rendering its abundant electroactive inter-/surface and rapid PF_(6)^(-)transport.Theoretical calculations authenticate that fluorine-doped porous carbon possesses lower PF_(6)^(-)adsorption energy and stronger interaction with PF_(6)^(-).Thanks to the remarkable structural/compositional superiority,when served as a positive electrode toward lithium-ion capacitors,the commercial-level fluorine-doped porous carbon showcases the record-breaking electrochemical properties within a wider working window of 2.5-5.0 V(vs Li/Li^(+))in terms of high-rate specific capacitances and long-duration stability,much superior to commercial activated carbon.More significantly,the 4.5 V-class graphite//fluorine-doped porous carbon lithium-ion capacitors are first constructed and manifest competitive electrochemical behaviors with long-cycle life,modest polarization,and large energy density.Our work provides a commendable positive paradigm and contributes a major step forward in next-generation lithium-ion capacitors and even other high-energy density metal-ion capacitors.展开更多
The dual system capable of solar-driven interfacial steam production and all-weather hydropower generation is emerging as a potential way to alleviate freshwater shortage and energy crisis.However,the intrinsic mechan...The dual system capable of solar-driven interfacial steam production and all-weather hydropower generation is emerging as a potential way to alleviate freshwater shortage and energy crisis.However,the intrinsic mechanism of hydroelectricity generation powered by the interaction between seawater and material structure is vague,and it remains challenging to develop dual-functional evaporators with high photothermal conversion efficiency and ionic selectivity.Herein,an all-weather dual-function evaporator based on porous carbon fiber-like(PCF)is acquired through the pyrolysis of barium-based metal-organic framework(Ba-BTEC),which is originated from waste polyimide.The PCF-based evaporator/device exhibits a high steam generation rate of 2.93 kg m^(-2)h^(-1)in seawater under 1 kW m^(-2)irradiation,along with the notable opencircuit voltage of 0.32 V,owing to the good light absorption ability,optimal wettability,and suitable aperture size.Moreover,molecular dynamics simulation result reveals that Na+tends to migrate rapidly within the nanoporous channels of PCF,owing to a strong affinity between oxygen-containing functional group and water molecules.This work not only proposes an eco-friendly strategy for constructing low-cost fulltime freshwater-hydroelectric co-generation device,but also contributes to the understanding of evaporation-driven energy harvesting technology.展开更多
Heteroatom-doped porous carbon materials have been widely studied due to their high specific surface area and high heteroatom content,but it is difficult to achieve high specific surface area and high heteroatom conte...Heteroatom-doped porous carbon materials have been widely studied due to their high specific surface area and high heteroatom content,but it is difficult to achieve high specific surface area and high heteroatom content at the same time.Herein,a simple method is introduced to prepare N/O co-doped hierarchical porous carbon materials(DNZKs).Phthalonitrile resins(DNZs)were prepared by using 1,3-bis(3,4-dicyanophenoxy)benzene as raw material and ZnCl_(2)/urea as composite curing agent,and then using KOH as activator to successfully prepare DNZKs with high specific surface area,developed pores and high N/O content.The porous carbon material(DNZK@400)obtained at a curing temperature of 400℃ has the highest N content(4.97%(mass)),a large specific surface area(2026 m^(2)·g^(-1)),a high micropore proportion(0.9),a high O content(7.53%(mass)),and the best specific capacitance(up to 567 F·g^(-1) at 0.1 A·g^(-1)),which can be attribute to the high temperature resistance of the nitrogencontaining aromatic heterocyclic structure in DNZs.When the mass ratio of resin and KOH is 1:1,the specific capacitance of the sample tested by the acid three-electrode system is obtained,and it is found that the material has high cycling stability(119%specific capacitance retention after 100,000 cycle tests).This work proposes a simple and easy-to-operate method for the preparation of multifunctional porous carbon.展开更多
基金supported by the National Key R&D Program of China(2022YFB3803700)National Natural Science Foundation of China(52171186)+1 种基金Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)support from“Zhiyuan Honor Program”for doctoral students,Shanghai Jiao Tong University.
文摘Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.
文摘The development of sustainable electrode materials for energy storage systems has become very important and porous carbons derived from biomass have become an important candidate because of their tunable pore structure,environmental friendliness,and cost-effectiveness.Recent advances in controlling the pore structure of these carbons and its relationship between to is energy storage performance are discussed,emphasizing the critical role of a balanced distribution of micropores,mesopores and macropores in determining electrochemical behavior.Particular attention is given to how the intrinsic components of biomass precursors(lignin,cellulose,and hemicellulose)influence pore formation during carbonization.Carbonization and activation strategies to precisely control the pore structure are introduced.Finally,key challenges in the industrial production of these carbons are outlined,and future research directions are proposed.These include the establishment of a database of biomass intrinsic structures and machine learning-assisted pore structure engineering,aimed at providing guidance for the design of high-performance carbon materials for next-generation energy storage devices.
基金supported by the National Natural Science Foundation of China(No.51803041)the University and Local Integration Development Project of Yantai,China(No.2022 XDRHXMXK08).
文摘Herein,an external crosslinker facilitated the hypercrosslinking of ferrocene and a nitrogen heterocyclic compound(either melamine or imidazole)through a direct Friedel-Crafts reaction,which led to the formation of nitrogen-containing hypercrosslinked fer-rocene polymer precursors(HCP-FCs).Subsequent carbonization of these precursors results in the production of iron-nitrogen-doped por-ous carbon absorbers(Fe-NPCs).The Fe-NPCs demonstrate a porous structure comprising aggregated nanotubes and nanospheres.The porosity of this structure can be modulated by adjusting the iron and nitrogen contents to optimize impedance matching.The uniform dis-tribution of Fe-N_(x)C,N dipoles,andα-Fe within the carbon matrix can be ensured by using hypercrosslinked ferrocenes in constructing porous carbon,providing the absorber with numerous polarization sites and a conductive network.The electromagnetic wave absorption performance of the specially designed Fe-NPC-M_(2)absorbers is satisfactory,revealing a minimum reflection loss of-55.3 dB at 2.5 mm and an effective absorption bandwidth of 6.00 GHz at 2.0 mm.By utilizing hypercrosslinked polymers(HCPs)as precursors,a novel method for developing highly efficient carbon-based absorbing agents is introduced in this research.
基金supports from the National Natural Science Foundation of China(22075034,22178037,and 22478047)Natural Science Foundation of Liaoning Province of China(2021-MS-303)the China Scholarship Council(CSC No 202008210171).
文摘Porous carbons hold broad application prospects in the domains of electrochemical energy storage devices and sensors.In this study,porous carbon derived from sodium alginate-encapsulated ZIF-8(SA/ZIF-8-C)was suc-cessfully prepared by blending ZIF-8 particles with sodium alginate,forming hydrogel beads in the presence of divalent metal ions,and subsequently subjecting them to high-temperature pyrolysis.Various characterization techniques were employed to evaluate the properties of the prepared materials.The introduction of a carbon framework on ZIF-8-derived particles effectively enhanced the conductivity of the prepared materials.The SA/ZIF-8(1.0)-C sample heated at 800℃exhibited a specific capacitance of up to 208 F g^(-1)at a current density of 0.5 A g^(-1)and outstanding cyclic stability.Even after 10,000 charge and discharge cycles,its capacitance retention rate remained as high as 87.14%.The symmetric supercapacitor constructed with the composite demonstrated an excellent energy density of 14.58 Wh kg^(-1)at a power capacity of 403.85 W kg^(-1).The implementation of this study provides new ideas and inspiration for the development of high-performance supercapacitors.
文摘Hierarchical porous carbon(HPC)materials exhibit superior performance profiles in various applications due to their well-developed multiscale interconnected pore structures.The synthesis of HPC from natural biomass precursors instead of fossil fuel-based precursors has gained considerable attention in recent decades.Rice husk,a globally abundant agricultural waste,offers a sustainable and cost-effective precursor for HPC production.The structural components and inherent silica content of rice husk act as a natural self-template for forming hierarchical pore structures with superior characteristics.In this review,recent studies on preparing rice husk-based HPC are summarized,and synthesis techniques are evaluated.In addition,recent advancements in activation methods and the effect of silica templates are reviewed while comparing these with traditional activated carbon production methods.Potential future directions for research and development activities are also discussed.Rice husk is a highly promising candidate for producing high-performance HPC materials.
基金financial support from the National Natural Science Foundation of China(Nos.22108258 and 52003251)Program for Science&Technology Innovation Talents in Universities of Henan Province(24HASTIT004)+1 种基金Outstanding Youth Fund of Henan Scientific Committee(222300420085)Science and Technology Joint Project of Henan Province(222301420041)。
文摘Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and fillers.In this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate MMMs.The dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting MMMs.Concurrently,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in MMMs.As a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH_(4) selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper bound.Additionally,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@ZnO.In summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials.
基金Natural Science Foundation of China(22134005,22204011)Chongqing Talents Program for Outstanding Scientists(cstc2021ycjh-bgzxm0179)。
文摘Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of operation.However,the low adsorption capacity of the reported adsorbents is still a challenge for wastewater treatment with highefficiency.Here,we developed a super adsorbent(SUA-1),which was a kind of porous carbon nanofibers derived from a composite of PAN-based electrospinning and ZIF-8(PAN/ZIF-8)via simple heat treatment process.The asprepared SUA showed an ultra-high adsorption capacity for adsorbing methyl blue(MB)at nearly three times its own weight,as high as 2998.18 mg/g.A series tests demonstrated that the pore-making effect of ZIF-8 during heat treatment process endowed high BET surface area and generated ZnO components as chemical adsorption center.Under the synergistic effect of bonding and non-bonding forces including ionic bond,electrostatic interaction,andπ-πinteraction,the adsorption capacity has been greatly improved.In view of promising efficiency,this work provides guidance and insights for the preparation of highly efficient adsorbents based on electrospinning derived porous carbon nanofibers.
基金National Natural Science Foundation of China(22262034)。
文摘With the development of electronics and portable devices,there is a significant drive to develop electrode materials for supercapacitors that are lightweight,economical,and provide high energy and power densities.Lignin-based porous carbons have recently been extensively studied for en-ergy storage applications because of their characteristics of large specific surface area,easy doping,and high conductivity.Significant progress in the synthesis of porous carbons derived from lignin,using different strategies for their preparation and modification with heteroatoms,metal oxides,met-al sulfides,and conductive polymers is considered and their electrochemical performances and ion storage mechanisms are discussed.Considerable fo-cus is directed towards the challenges encountered in using lignin-based por-ous carbons and the ways to optimize specific capacity and energy density for supercapacitor applications.Finally,the limitations of existing technolo-gies and research directions for improving the performance of lignin-based carbons are discussed.
基金supported by Basic and Applied Basic Research Fund Project of Guangdong(2022A1515011817,2023A1515030160)Research and Innovation Group of Guangdong University of Education(2024KYCXTD014)。
文摘The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous carbon nanosheets doped with both Fe and Ni(Fe/Ni-N-PCNSs)by an easy and template-free approach that solve this problem.Because of their ultrathin porous 2D structure and uniform distribution of Fe and Ni dopants,they capture polysulfides,speed up the sulfur redox reaction,and improve the material’s lithiophilicity,greatly suppressing the shuttling of polysulfides and dendrite growth on the lithium anode.As a result,it has an exceptional performance as a stable host for elemental sulfur and metallic lithium,producing a record long life of 1000 cycles with a very small capacity decay of 0.00025%per cycle in a Li-S battery and an excellent cycling stability of over 850 h with a small overpotential of>72 mV in a lithium metal battery.This work suggests the use of multifunctional-based 2D porous carbon nanosheets as a stable host for both elemental sulfur and metallic lithium to improve the Li-S battery per-formance.
文摘Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.
文摘The typical method for preparing the porous carbon used in supercapacitors(SCs)is time-consuming and energy-intensive.We report a fast and efficient route to synthesize and tailor the structure of porous carbon by a Joule heating technique(JHT)using phenolic resin and precursors.During the JHT process,the time and energy needed are both significantly reduced because the precursor is heated to the target temperature at a rate of 1100 K/s,so the porous carbon is formed with the release of small molecules and the etching of the substrate by K_(2)CO_(3).JHT has a higher energy efficiency than traditional carbonization methods in a tube furnace and allows for precise control of the pyrolysis process,thus achieving better control of the material’s structure and properties.Samples obtained by JHT contain abundant pores and a large specific surface area(1652.7 m^(2)/g),which give an excellent specific capacitance of 476.0 F/g and rate capability(75.1%capacitance retention at 64.0 A/g in an aqueous alkaline electrolyte).Furthermore,in electrolytes of 17.0 mol/kg NaClO_(4)(water-in-salt)and 1.0 mol/L TEABF4/AN,the symmetric SCs have a maximum energy density of 33.3 and 50.8 Wh/kg at power densities of 220.4 and 376.4 W/kg,respectively.The cells also have good long-term stability,with a nearly 100%Coulombic efficiency,and a capacitance retention of 93.1%in a water-in-salt electrolyte after 10000 cycles,and 88.9%in an organic electrolyte after 8000 cycles.This study shows that JHT has the potential to serve as an ultra-fast method to prepare porous carbons for energy storage.
基金supported by the National Key R&D Program of China(2020YFA0711502)the National Natural Science Foundation of China(51972299,52003265,52202052,52273234,52273239,52373310).Fei Pan is supported by the Xiaomi Young Talents Program.
文摘The search for novel carbons has been an important research topic for developing high-performance anodes of lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs).In this study,we fabricated a new carbon,long-range ordered porous carbon(LOPC),by inducing covalent bonds between face-centered cubic C_(60)(fcc C_(60))cages in a molecular crystal via electron injection under vacuum at~520°C.The LOPC maintains the periodic lattice of the fcc C_(60)molecular crystal but has improved structural stability and electrical conductivity because of the sp^(2)bonding formed between C_(60)molecules.Compared with fcc C_(60),which has a much greater specific surface area(327.1 m^(2)·g^(−1)),LOPC has a specific capacity of 820.9 mA·h·g^(−1)or 292.9 mA·h·g^(−1)as an anode for LIBs or SIBs,both of which are measured at a current density of 0.1 A·g^(−1).This porous yet ordered carbon may open new opportunities for anode materials in electrochemical energy storage.
基金supported by the National Key R&D Program(2022YFC3902403)Fundamental Research Funds for the Central Universities(2024JC001,2019JG002)Technology Innovation Special Fund of Jiangsu Province for Carbon Dioxide Emission Peaking and Carbon Neutrality(BE2022307)。
文摘To optimize the CO_(2) adsorption performance of carbon materials,this study proposed a preparation method for biomass-based porous carbon through hydrothermal carbonization coupled with nitrogen source optimization and K_(2)CO_(3) activation.The effects of different nitrogen sources(urea,piperazine,melamine,and polyaniline)and activation temperatures on the physicochemical features and CO_(2) adsorption characteristics of the porous carbons were systematically investigated.The results indicated that different nitrogen sources showed varying impacts on the CO_(2) uptake of porous carbons,and not all nitrogen sources enhanced the adsorption performance.The urea and piperazine doped porous carbons exhibited relatively low nitrogen contents and specific surface areas.Whereas the melamine doped carbons showed higher nitrogen contents and specific surface areas,but lacked narrow micropores,limiting their CO_(2) adsorption performance.In contrast,PAC-700,prepared using polyaniline as nitrogen source,featured a well-developed pore structure,abundant narrow micropores and pyrrolic-N groups,endowing it with enhanced CO_(2) adsorption capability.At 0℃/1 bar and 25℃/1 bar,the CO_(2) uptake of PAC-700 reached 6.85 and 4.64 mmol/g,respectively.Additionally,PAC-700 maintained a CO_(2) uptake retention ratio of 99%after 5 adsorption-desorption cycles and exhibited good CO_(2)/N_(2) selectivity of 22.4−51.6.These findings highlighted the advantageous CO_(2) adsorption performance of PAC-700,indicating its substantial application potential in the domain of carbon capture.
基金Project(52174338)supported by the National Natural Science Foundation of ChinaProjects(2022JJ20086,2021JJ30796)supported by the Natural Science Foundation of Hunan Province,China+1 种基金Project(2023CXQD005)supported by the Central South University Innovation-Driven Research Programme,ChinaProject(23B0841)supported by the Education Department of Hunan Provincial Government,China。
文摘Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost.
基金supported by the Open Project of Xiangjiang Laboratory (22XJ03026)the National Natural Science Foundation of China (72004060)+3 种基金the Provincial Natural Science Foundation of Hunan Province (2022JJ30015)the Scientific Research Project of Hunan Education Department, China (23A0457)Environmental Protection Scientific Research Project of Hunan Province (HBKT2021021)the “Digital-intelligence+” interdisciplinary research project of Hunan University of Technology and Business (2023SZJ22)
文摘The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.
基金supported by the National Natural Science Foundation of China(No.22309056)the National Key R&.D Program of China(No.2022YFB2404800)+4 种基金the Basic Research Program of Shenzhen Municipal Science and Technology Innovation Committee(No.JCYJ20210324141613032)the Knowledge Innovation Project of Wuhan City(No.2022010801010303)the City University of Hong Kong Strategic Research Grant(SRG),Hong Kong,China(No.7005505)the City University of Hong Kong Donation Research Grant,Hong Kong,China(No.DON-RMG 9229021)the Postdoctoral Fellowship Program of CPSF(No.GZB20230552).
文摘Antimony(Sb)is regarded as a potential candidate for next-generation anode materials for rechargeable batteries because it has a high theoretical specific capacity,excellent conductivity and appropriate reaction potential.However,Sb-based anodes suffer from severe volume expansion of>135%during the lithiation-delithiation process.Hence,we construct a novel Sb@C composite encapsulating the Sb nanoparticles into highly conductive three-dimensional porous carbon frameworks via the one-step magnesiothermic reduction(MR).The porous carbon provides buffer spaces to accommodate the volume expansion of Sb.Meanwhile,the three-dimensional(3D)interconnected carbon frameworks shorten the ion/electron transport pathway and inhibit the overgrowth of unstable solid-electrolyte interfaces(SEIs).Consequently,the 3D Sb@C composite displays remarkable electrochemical performance,including a high average Coulombic efficiency(CE)of>99%,high initial capability of 989 mAh·g^(-1),excellent cycling stability for over 1000 cycles at a high current density of 5 A·g^(-1).Furthermore,employing a similar approach,this 3D Sb@C design paradigm holds promise for broader applications across fast-charging and ultralong-life battery systems beyond Li+.This work aims to advance practical applications for Sb-based anodes in next-generation batteries.
基金supported by the National Natural Science Foundation of China(22408061 and 22468005)Program for Introducing High-Level Talents from Guangxi University,and Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology(2023Z014).
文摘Oxygen-rich porous carbons are promising candidates for the carbon-based cathodes of zinc ion hybrid capacitors(ZIHCs).Potassium activation is a traditional and effective way to prepare oxygen-rich porous carbons.Efficient potassium activation is the key to develop high-performance oxygen-rich porous carbon cathodes.Herein,the alkali lignin,extracted from eucalyptus wood by geopolymer-assisted low-alkali pretreatment,is used to prepare oxygen-rich lignin-derived porous carbons(OLPCs)through KOH activation and K_(2)CO_(3)activation at 700-900℃.KOH activation constructs a hierarchical micro-mesoporous structure,while K_(2)CO_(3)activation constructs a microporous structure.Furthermore,K_(2)CO_(3)activation could more efficiently construct active oxygen(C=O)species than KOH activation.The OLPCs prepared by KOH/K_(2)CO_(3)activations at 800℃show the highest microporosity(78.4/87.7%)and C=O content(5.3/8.0 at.%).Due to that C=O and micropore adsorb zinc ions,the OLPCs prepared by K_(2)CO_(3)activation at 800℃with higher C=O content and microporosity deliver superior capacitive performance(256 F g^(-1)at 0.1 A g^(-1))than that by KOH activation at 800℃(224 F g^(-1)at 0.1 A g^(-1)),and excellent cycling stability.This work provides a new insight into the sustainable preparation of oxygenrich porous carbon cathodes through efficient potassium activation for ZIHCs.
基金support from the National Natural Science Foundation of China(Grant No.U22A20145,51904115,52072151,52171211,52102253,and 52271218)Jinan Independent Innovative Team(2020GXRC015)Major Program of Shandong Province Natural Science Foundation(ZR2023ZD43,ZR2021ZD05).
文摘Low specific capacitances and/or limited working potential(≤4.5 V).of the prevalent carbon-based positive electrodes as the inborn bottleneck seriously hinder practical advancement of lithium-ion capacitors.Thus,breakthroughs in enhancement of both specific capacitances and upper cutoff potentials are enormously significant for high-energy density lithium-ion capacitors.Herein,we first meticulously design and scalably fabricate a commercializable fluorine-doped porous carbon material with competitive tap density,large active surface,appropriate aperture distribution,and promoted affinity with the electrolyte,rendering its abundant electroactive inter-/surface and rapid PF_(6)^(-)transport.Theoretical calculations authenticate that fluorine-doped porous carbon possesses lower PF_(6)^(-)adsorption energy and stronger interaction with PF_(6)^(-).Thanks to the remarkable structural/compositional superiority,when served as a positive electrode toward lithium-ion capacitors,the commercial-level fluorine-doped porous carbon showcases the record-breaking electrochemical properties within a wider working window of 2.5-5.0 V(vs Li/Li^(+))in terms of high-rate specific capacitances and long-duration stability,much superior to commercial activated carbon.More significantly,the 4.5 V-class graphite//fluorine-doped porous carbon lithium-ion capacitors are first constructed and manifest competitive electrochemical behaviors with long-cycle life,modest polarization,and large energy density.Our work provides a commendable positive paradigm and contributes a major step forward in next-generation lithium-ion capacitors and even other high-energy density metal-ion capacitors.
基金supported by National Natural Science Foundation of China(No.52373099)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)。
文摘The dual system capable of solar-driven interfacial steam production and all-weather hydropower generation is emerging as a potential way to alleviate freshwater shortage and energy crisis.However,the intrinsic mechanism of hydroelectricity generation powered by the interaction between seawater and material structure is vague,and it remains challenging to develop dual-functional evaporators with high photothermal conversion efficiency and ionic selectivity.Herein,an all-weather dual-function evaporator based on porous carbon fiber-like(PCF)is acquired through the pyrolysis of barium-based metal-organic framework(Ba-BTEC),which is originated from waste polyimide.The PCF-based evaporator/device exhibits a high steam generation rate of 2.93 kg m^(-2)h^(-1)in seawater under 1 kW m^(-2)irradiation,along with the notable opencircuit voltage of 0.32 V,owing to the good light absorption ability,optimal wettability,and suitable aperture size.Moreover,molecular dynamics simulation result reveals that Na+tends to migrate rapidly within the nanoporous channels of PCF,owing to a strong affinity between oxygen-containing functional group and water molecules.This work not only proposes an eco-friendly strategy for constructing low-cost fulltime freshwater-hydroelectric co-generation device,but also contributes to the understanding of evaporation-driven energy harvesting technology.
基金supported by the National Natural Science Foundation of China(51673033 and 52073038)the Fundamental Research Funds for the Central Universities(DUT22LAB605).
文摘Heteroatom-doped porous carbon materials have been widely studied due to their high specific surface area and high heteroatom content,but it is difficult to achieve high specific surface area and high heteroatom content at the same time.Herein,a simple method is introduced to prepare N/O co-doped hierarchical porous carbon materials(DNZKs).Phthalonitrile resins(DNZs)were prepared by using 1,3-bis(3,4-dicyanophenoxy)benzene as raw material and ZnCl_(2)/urea as composite curing agent,and then using KOH as activator to successfully prepare DNZKs with high specific surface area,developed pores and high N/O content.The porous carbon material(DNZK@400)obtained at a curing temperature of 400℃ has the highest N content(4.97%(mass)),a large specific surface area(2026 m^(2)·g^(-1)),a high micropore proportion(0.9),a high O content(7.53%(mass)),and the best specific capacitance(up to 567 F·g^(-1) at 0.1 A·g^(-1)),which can be attribute to the high temperature resistance of the nitrogencontaining aromatic heterocyclic structure in DNZs.When the mass ratio of resin and KOH is 1:1,the specific capacitance of the sample tested by the acid three-electrode system is obtained,and it is found that the material has high cycling stability(119%specific capacitance retention after 100,000 cycle tests).This work proposes a simple and easy-to-operate method for the preparation of multifunctional porous carbon.
