Solid-state lithium batteries are flourishing due to their excellent potential energy density.Substantial efforts have been made to improve their electrochemical performance by increasing the conductivity of solid-sta...Solid-state lithium batteries are flourishing due to their excellent potential energy density.Substantial efforts have been made to improve their electrochemical performance by increasing the conductivity of solid-state electrolytes(SEs)and designing a compatible battery configuration.The safety of a solid lithium battery has generally been taken for granted due to the nonflammability and strength of SEs.However,recent results have shown the release of dangerous gases and intense heat due to the formation of lithium dendrites,indicating the safety of solid-state lithium batteries may have been overestimated.In this review,we introduce a safety evaluation methodology,then focus on the garnet Li_(7)La_(3)Zr_(2)O_(12)(LLZO)and sulfide-based SEs,summarizing their structure,conductivity,compatibility with a lithium metal anode,electrochemical/chemical stability,and mechanical/thermal stability,which correlate closely with battery safety.We also evaluate the safety of all-solid-state lithium batteries,then conclude by discussing future avenues for improving the safety of SE-based batteries.展开更多
The development of low-cost and eco-friendly gel polymer electrolytes (GPEs) with a wide window, ideal compatibility, and structural stability is an effective measure to achieve safe high-energy-density lithium-metal ...The development of low-cost and eco-friendly gel polymer electrolytes (GPEs) with a wide window, ideal compatibility, and structural stability is an effective measure to achieve safe high-energy-density lithium-metal batteries. Herein, a biodegradable composite polyacrylonitrile/poly-L-lactic acid nanofiber membrane (PAL) is synthesized and used as a robust skeleton for GPEs. The 3D nanofiber membrane (PAL-3-C12) prepared with an adjusted weight ratio of polyacrylonitrile (PAN)/poly-L-lactic acid (PLLA) and spinning solution concentration delivers decent thermal stability, biodegradability, and liquid electrolyte absorbability. The “passivation effect” of PAN upon lithium metal is effectively alleviated by hydrogen bonds formed in the PAL chains. These advantages enable PAL GPEs to work stably to 5.17 V while maintaining high ionic conductivity as well as excellent corrosion resistance and dielectric properties. The interfacial compatibility of optimized GPEs promotes the stable operation of a Li||PAL-3-C12 GPEs||Li symmetric battery for 1000 h at 0.15 mA cm^(−2)/0.15 mA h cm^(−2), and the LiFePO4 full cell retains capacity retention of 97.63% after 140 cycles at 1C.展开更多
Solar-driven CO_(2)conversion to chemical fuels in an aqueous solution is restricted not only by photocatalysts but also by mass transfer.Here,a regulatable three-phase interface on a porous fixed-bed is constructed f...Solar-driven CO_(2)conversion to chemical fuels in an aqueous solution is restricted not only by photocatalysts but also by mass transfer.Here,a regulatable three-phase interface on a porous fixed-bed is constructed for efficient C-C coupling in photocatalytic CO_(2)reduction.The photocatalytic results show that∼90%selectivity towards C^(2+)products is obtained by a Cu/Cd_(0.5)Zn_(0.5)S photocatalyst,with a yield of 6.54μmol/h(an irradiation area of 0.785 cm^(2)),while only 0.94μmol/h(an irradiation area of 19.625 cm^(2))is achieved with a commonly used suspension photocatalytic reactor.We find that under the same CO_(2)feed rate,the local CO_(2)concentration in this porous fixed-bed photoreactor is obviously higher than in the suspension photoreactor.The larger local CO_(2)coverage derived from a higher CO_(2)supply and aggregation enhances the C-C coupling,thereby generating more C^(2+).Even an observable three-phase interface on the porous fixed-bed can be regulated by adjusting the CO_(2)supply,for which the optimal gas inlet rate is 5-10 sccm.展开更多
Electrocatalytic CO_(2) reduction(ECR)to high value-added chemicals by using renewable electricity presents a promising strategy to realize“carbon neutrality”.However,the ECR system is still limited by its low curre...Electrocatalytic CO_(2) reduction(ECR)to high value-added chemicals by using renewable electricity presents a promising strategy to realize“carbon neutrality”.However,the ECR system is still limited by its low current density and poor CO_(2) utilization efficiency.Herein,by using the confinement effect of covalent organic frame-works(COFs)to confine the in-situ growth of metal nanoclusters(NCs),we develop a series of Cu NCs encap-sulated on COF catalysts(Cu-NC@COF)for ECR.Among them,Cu-NC@CuPc-COF as a gas diffusion electrode(GDE)achieves a maximum CO_(2)-to-CH_(4) Faradaic efficiency of 74±3%(at-1.0 V vs.Reversible Hydrogen Electrode(RHE))with a current density of 538±31 mA cm^(-2)(at-1.2 V vs.RHE)in a flow cell,making it one of the best among reported materials.More importantly,the current density is much higher than the relevant industrial current density(200 mA cm^(-2)),indicating the potential for industrial application.This work opens up new possibilities for the design of ECR catalysts that utilize synergistic strategy.展开更多
The efficiency and stability of typical three-dimensional(3D)MAPbI_(3)perovskite-based solar cells are highly restricted,due to the weak interaction between methylammonium(MA^(+))and[PbI 6]4-octahedra in the 3D struct...The efficiency and stability of typical three-dimensional(3D)MAPbI_(3)perovskite-based solar cells are highly restricted,due to the weak interaction between methylammonium(MA^(+))and[PbI 6]4-octahedra in the 3D structure,which can cause the ion migration and the related defects.Here,we found that the in situ-grown perovskitoid TEAPbI_(3)layer on 3D MAPbI_(3)can inhibit the MA^(+)migration in a polar solvent,thus enhancing the thermal and moisture stability of perovskite films.The crystal structure and orientation of TEAPbI_(3)are reported for the first time by single crystal and synchrotron radiation analysis.The ultra-thin perovskitoid layer can reduce the trap states and accelerate photo-carrier diffusion in perovskite solar cells,as confirmed by ultra-fast spectroscopy.The power conversion efficiency of TEAPbI_(3)-MAPbI_(3)based solar cells increases from 18.87%to 21.79%with enhanced stability.This work suggests that passivation and stabilization by in situ-grown perovskitoid can be a promising strategy for efficient and stable perovskite solar cells.展开更多
Magnesium-ion batteries(MIBs)are promising alternatives to lithium-ion batteries due to their safety and high theoretical specific capacity,and the abundance of magnesium reserves.However,their anodes and electro-lyte...Magnesium-ion batteries(MIBs)are promising alternatives to lithium-ion batteries due to their safety and high theoretical specific capacity,and the abundance of magnesium reserves.However,their anodes and electro-lytes severely restrict the development of MIBs,so alloy-type anodes provide an effective strategy to circum-vent the surface passivation issue encountered with Mg metal in conventional electrolytes.Theoretically,a germanium anode can deliver a high specific capacity of 1476 mAh g?1,but hitherto,no experimental reports have described Ge in MIBs.Herein,we experimentally verified that Ge could reversibly react with Mg 2þions through the design of dual-phase Ge–Bi film electrodes fabricated by magnetron co-sputtering.Notably,a Ge 57 Bi 43 electrode delivered a high specific capacity of 847.5 mAh g?1,owing to the joint alloying reactions of Ge and Bi with Mg,which was much higher than the specific capacity of Bi(around 385 mAh g?1).Moreover,the Ge–Bi anode showed excellent rate performance,good cycling stability,and superior compatibility with conventional electrolytes such as Mg(TFSI)2.More importantly,the Mg storage mechanism of the Ge–Bi anode was unveiled by operando X-ray diffraction,and density functional theory calculations rationalized that the introduction of Bi to form Ge–Bi evidently decreased the defect formation energy and effectively boosted the electrochemical reactivity of Ge with Mg.展开更多
Molten ZnCl_(2)hydrates are ionic liquids at room temperature,which exhibit intriguing physical and electrochemical properties.Continuous efforts have been devoted over several decades to understanding the properties ...Molten ZnCl_(2)hydrates are ionic liquids at room temperature,which exhibit intriguing physical and electrochemical properties.Continuous efforts have been devoted over several decades to understanding the properties of the molten ZnCl_(2)hydrates that have been dubbed as water-in-salt electrolytes recently.The physical properties of molten ZnCl_(2)hydrates can be described from the perspectives of ions in their speciation and water molecules regarding their chemical environments.Recently,attention has been given to molten ZnCl_(2)hydrates as electrolytes for Zn metal batteries.It was revealed that the physical properties of such electrolytes have rich implications in their electrochemical properties.Therefore,it demands a holistic understanding of the physical and electrochemical properties of molten ZnCl_(2)hydrates to design functional electrolytes to serve high-performing Zn metal batteries.This perspective attempts to review the works that described the properties of concentrated ZnCl_(2)as an ionic liquid and as an emerging electrolyte.The author also provides a perspective to highlight the needs of future research to circumvent the limits of this electrolyte.展开更多
The Li-O_(2) battery(LOB)has attracted growing interest,including for its great potential in next-generation energy storage systems due to its extremely high theoretical specific capacity.However,a series of challenge...The Li-O_(2) battery(LOB)has attracted growing interest,including for its great potential in next-generation energy storage systems due to its extremely high theoretical specific capacity.However,a series of challenges have seriously hindered LOB development,such as sluggish kinetics during the oxygen reduction and oxygen evolution reactions(ORR/OER)at the cathode,the formation of lithium dendrites,and undesirable corrosion at the lithium metal anode.Herein,we propose a strategy based on the ultra-low loading of atomic Ni catalysts to simultaneously boost the ORR/OER at the cathode while stabilizing the Li metal anode.The resultant LOB delivers a superior discharge capacity(>16,000 mAh g^(-1)),excellent long-term cycling stability(>200 cycles),and enhanced high rate capability(>300 cycles@500 mA g^(-1)).The working mechanisms of these atomic Ni catalysts are revealed through carefully designed in situ experiments and theoretical calculations.This work provides a novel research paradigm for designing high-performance LOBs that are useable in practical applications.展开更多
With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention f...With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention for their energy density,safety,and low cost,but problems with the zinc anode—such as hydrogen evolution,corrosion,passivation,dendrite proliferation,and deformation—have led to zinc–air batteries with low Coulombic efficiency and short cycle life;these remain the key obstacles hindering the batteries’further development.In this review paper,we briefly describe the reaction mechanism of zinc–air batteries,then summarize the strategies for solving the key issues in zinc anodes.These approaches are divided into three aspects:structural designs for the zinc anode;interface engineering;and electrolyte selection and optimization.We finish by offering some suggestions for future research directions to improve the zinc anode in zinc–air batteries.展开更多
The anionic redox reaction(ARR)is a promising charge contributor to improve the reversible capacity of layeredoxide cathodes for Na-ion batteries;however,some practical bottlenecks still need to be eliminated,includin...The anionic redox reaction(ARR)is a promising charge contributor to improve the reversible capacity of layeredoxide cathodes for Na-ion batteries;however,some practical bottlenecks still need to be eliminated,including a low capacity retention,large voltage hysteresis,and low rate capability.Herein,we proposed a high-Na content honeycomb-ordered cathode,P2–Na_(5/6)[Li_(1/6)Cu_(1/6)Mn_(2/3)]O_(2)(P2-NLCMO),with combined cationic/anionic redox.Neutron powder diffraction and X-ray diffraction of P2-NLCMO suggested P2-type stacking with rarely found P6322 symmetry.In addition,advanced spectroscopy techniques and density functional theory calculations confirmed the synergistic stabilizing relationship between the Li/Cu dual honeycomb centers,achieving fully active Cu^(3+)/Cu^(2+) redox and stabilized ARR with interactively suppressed local distortion.With a meticulously regulated charge/discharge protocol,both the cycling and rate capability of P2-NLCMO were significantly.展开更多
Molybdenum-based materials have stepped into the spotlight as promising electrodes for energy storage systems due to their abundant valence states,low cost,and high theoretical capacity.However,the performance of conv...Molybdenum-based materials have stepped into the spotlight as promising electrodes for energy storage systems due to their abundant valence states,low cost,and high theoretical capacity.However,the performance of conventional molybdenum-based electrode materials has been limited by slow diffusion dynamics and deficient thermodynamics.Applying defect engineering to molybdenum-based electrode materials is a viable method for overcoming these intrinsic limitations to realize superior electrochemical performance for energy storage.Herein,we systematically review recent progress in defect engineering for molybdenum-based electrode materials,including vacancy modulation,doping engineering,topochemical substitution,and amorphization.In particular,the essential optimization mechanisms of defect engineering in molybdenum-based electrode materials are pre-sented:accelerating ion diffusion,enhancing electron transfer,adjusting potential,and maintaining structural stability.We also discuss the existing challenges and future objectives for defect engineering in molybdenum-based electrode materials to realize high-energy and high-power energy storage devices.展开更多
Stabilizing the highly active RuO_(2) electrocatalyst for the oxygen evolution reaction(OER)is critical for the application of proton exchange membrane water electrolysis,but this remains challenging due to the inevit...Stabilizing the highly active RuO_(2) electrocatalyst for the oxygen evolution reaction(OER)is critical for the application of proton exchange membrane water electrolysis,but this remains challenging due to the inevitable over-oxidation of Ru in harsh oxidative environments.Herein,we describe constructing Ru-O-La asymmetric configurations into RuO_(2) via a facile sol-gel method to tailor electron redistribution and thereby eliminate the over-oxidation of Ru centers.Specifically,the as-prepared optimal La_(0.1)Ru_(0.9)O_(2) shows a low overpotential of 188 mV at 10 mA cm^(-2),a high mass activity of 251 A gRu^(-1) at 1.6 V vs.reversible hydrogen electrode(RHE),and a long-lasting durability of 63 h,far superior to the 8 h achieved by standard RuO_(2).Experiments and density functional theory calculations jointly reveal that the Ru-O-La asymmetric configuration could trigger electron redistribution in RuO_(2).More importantly,electron transfer from La to Ru via the Ru-O-La configuration could lead to increased electron density around Ru,thus preventing the over-oxidation of Ru.In addition,electron redistribution tunes the Ru 4d band center’s energy level,which optimizes the adsorption and desorption of oxygen intermediates.This work offers an effective strategy for regulating electronic structure to synergistically boost the activity and stability of RuO_(2)-based acidic OER electrocatalysts.展开更多
Regulating the pore structure of a zirfon-based diaphragm is critical to promoting a high-rate alkaline electrolyzer,but it is still a big challenge to respond“trade-off”between the thickness of the diaphragm and th...Regulating the pore structure of a zirfon-based diaphragm is critical to promoting a high-rate alkaline electrolyzer,but it is still a big challenge to respond“trade-off”between the thickness of the diaphragm and the current density/gas barrier behavior.In this work,a porous hydrophilic skin layer with~μm thick of polyvinyl alcohol(PVA)has been successfully constructed and casted onto the thin zirfon-type separator composite(V-Zirfon-350μm).The V-Zirfon-350μm separator generates a high KOH uptake(>90%),low area resistance(0.2026Ωcm^(2))but a low electrolyte permeation flux density(5.2×10^(-4) mL cm^(-2) s^(-1) at 0.5 bar),which largely surpasses the state-of-the-art commercial Zirfon UTP-500μm diaphragm.When coupled with Raney Ni cathode and NiCoMo-LDH anode catalysts,the V-Zirfon-350μm separator offers a high current density over 1300 mA cm^(-2)@2.0 V(80℃ in 30%KOH)and a superior stability of 300 h under 800 mA cm^(-2) for alkaline water electrolysis(AWE).Specifically,the voltage is merely~3.5 V for two electrolytic cells connected in series,which can be even conducted for more than 1300 h at different operational conditions.This work provides a novel methodology for the practical application of a thin Zirfon-based diaphragm.展开更多
Achieving carbon neutrality is an essential part of responding to climate change caused by the deforestation and over-exploitation of natural resources that have accompanied the development of human society.The carbon...Achieving carbon neutrality is an essential part of responding to climate change caused by the deforestation and over-exploitation of natural resources that have accompanied the development of human society.The carbon dioxide reduction reaction(CO_(2)RR)is a promising strategy to capture and convert carbon dioxide(CO_(2))into value-added chemical products.However,the traditional trial-and-error method makes it expensive and time-consuming to understand the deeper mechanism behind the reaction,discover novel catalysts with superior performance and lower cost,and determine optimal support structures and electrolytes for the CO_(2)RR.Emerging machine learning(ML)techniques provide an opportunity to integrate material science and artificial intelligence,which would enable chemists to extract the implicit knowledge behind data,be guided by the insights thereby gained,and be freed from performing repetitive experiments.In this perspective article,we focus on recent ad-vancements in ML-participated CO_(2)RR applications.After a brief introduction to ML techniques and the CO_(2)RR,we first focus on ML-accelerated property prediction for potential CO_(2)RR catalysts.Then we explore ML-aided prediction of catalytic activity and selectivity.This is followed by a discussion about ML-guided catalyst and electrode design.Next,the potential application of ML-assisted experimental synthesis for the CO_(2)RR is discussed.展开更多
Devising a desirable nano-heterostructured photoelectrode based on the charge transfer kinetics mechanism is a pivotal strategy for implementing efficient photoelectrocatalytic(PEC)technology,since the charge separati...Devising a desirable nano-heterostructured photoelectrode based on the charge transfer kinetics mechanism is a pivotal strategy for implementing efficient photoelectrocatalytic(PEC)technology,since the charge separation and utilization efficiency of a photoelectrode is critical to its PEC performance.Herein,we fabricate a F–Co_(3)O_(4)@Bi_(2)WO_(6) core–shell hetero-array photoanode by coupling Bi_(2)WO_(6) nanosheets with F–Co_(3)O_(4) nanowires using a simple solvothermal solution method.The three-dimensional hierarchical heterostructure has a homogeneous chemical interface,helping it to promote an S-scheme-based carrier transport kinetics and maintain excellent cycling stability.Charge density difference calculations verify the electron migration trend from F–Co_(3)O_(4) to Bi_(2)WO_(6) upon hybridization and the formation of an internal electric field in the heterojunction,consistent with the S-scheme mechanism,which is identified by in situ irradiation X-ray photoelectron spectroscopy and by ultraviolet photoelectron spectroscopy.The optimized F–Co_(3)O_(4)@Bi_(2)WO_(6)-2 photoelectrode achieves high carrier utilization efficiency and exhibits superior PEC degradation performance for various organic pollutants,including reactive brilliant blue KN-R,rhodamine B,sulfamethoxazole,and bisphenol A.This work not only reveals that F–Co_(3)O_(4)@Bi_(2)WO_(6)-2 is effective for PEC water remediation but also provides a strategy to enhance carrier transport kinetics by designing binary oxides.展开更多
The conventional perspective suggests that low-concentration electrolytes(LCEs)face challenges in achieving stable charge/discharge properties due to the decreased ionic conductivity resulting from lower Li^(+) concen...The conventional perspective suggests that low-concentration electrolytes(LCEs)face challenges in achieving stable charge/discharge properties due to the decreased ionic conductivity resulting from lower Li^(+) concentrations.However,the successful utilization of LCEs in lithium/sodium-ion batteries has brought them into the forefront of consideration for high performance battery systems.It is possible to achieve improved interface stability and ion transport performance for LCEs through adjusting electrolyte components,such as salts,solvents,and additives.This review provides timely update of the recent research progress,design strategies and remaining challenges of LCEs to answer several questions:i)What is the key factor for designing LCEs?ii)How to balance the low salt concentration and good ionic conductivity?iii)What is the interphasial mechanism of anode/cathode in LCEs?Firstly,the development of LCEs is discussed with typical examples.Subsequently,effectiveness of solvents on overall performances of LCEs is comprehensively summarized in detail.Finally,the challenges and possible research direction of LCEs are discussed.This review provides critical guidance for designing novel electrolytes for secondary batteries.展开更多
Energy is always closely correlated with the development of human society.Today,energy demand is growing rapidly,causing excessive CO_(2)emissions that are contributing to global warming and extreme weather events.Fro...Energy is always closely correlated with the development of human society.Today,energy demand is growing rapidly,causing excessive CO_(2)emissions that are contributing to global warming and extreme weather events.From industrial civilization to ecological civilization,the utilization of energy requires more environmentally friendly technologies,especially if we are to achieve the global goal of carbon neutrality.展开更多
Low-dimensional luminescent lead-free metal halides have received substantial attention due to their unique optoelectronic properties.Among them,zero-dimensional(0D)manganese(II)-based metal halides with negligible se...Low-dimensional luminescent lead-free metal halides have received substantial attention due to their unique optoelectronic properties.Among them,zero-dimensional(0D)manganese(II)-based metal halides with negligible self-absorption have emerged as potential candidates in X-ray scintillators.Herein,we for the first time report a novel lead-free(TBA)_(2)MnBr_(4) single crystal synthesized via a facile solvent evaporation method.In this crystal,[MnBr_(4)]^(2-)units are isolated by large TBA^(+)organic cations,resulting in a unique 0D structure.The prepared manganese-based crystals exhibit a bright-green emission centered at 512 nm with a high photoluminescence quantum yield(PLQY)of 93.76%at room temperature,originating from the ^(4)T_(1)–^(6)A_(1) transition of Mn^(2+).Apart from their outstanding optical performance,the crystals also show excellent stability and can maintain 94.4%of the initial PLQY even after being stored in air for 90 days.Flexible(TBA)_(2)MnBr4 films prepared as X-ray imaging scintillators exhibit a low detection limit of 63.3 nGyair/s,a high light yield of 68000 ph/MeV,and a high spatial resolution of 15.4 lp/mm.Thus,this work not only enriches the family of lead-free metal halides but also expands the application of manganese(II)-based halides in flexible X-ray scintillators.展开更多
Layer-number modulation in graphene has become a recent focus of research due to the superior degree of freedom that can be achieved in terms of magic-angle,wettability,superconductivity,and superlattices.However,the ...Layer-number modulation in graphene has become a recent focus of research due to the superior degree of freedom that can be achieved in terms of magic-angle,wettability,superconductivity,and superlattices.However,the intrinsic transport of multilayer graphene is indistinguishable in atmospheric adsorbates and supporting environment,and its underlying charge transfer mechanism has not yet been thoroughly determined.In this study,a shift in the charge neutrality point of trilayer graphene(TLG)is demonstrated to be regulated by three governing factors:oxygen gas(O_(2)),water molecules(H_(2)O),and thermally activated electrons.Absorbed O_(2) induces a high work function in semimetallic TLG,while H_(2)O is not an evident dopant but can strengthen binding against O_(2) desorption.A simplified model is developed to elucidate the competitive mechanism and charge transfer among these two dopants(O_(2),H_(2)O)and thermal electrons,and the model is demonstrated by work function regulation and Bader charge transfer based on density functional theory calculations.This study provides a strategy to explore transport modulation of multilayer graphene in the fields of ballistic transport and low power consumption of graphene field-effect transistors.展开更多
The large-scale synthesis of platinum-free electrocatalysts for the oxygen reduction reaction(ORR)remains a grand challenge.We report the large-scale production of stable and active ORR electrocatalysts based on iron,...The large-scale synthesis of platinum-free electrocatalysts for the oxygen reduction reaction(ORR)remains a grand challenge.We report the large-scale production of stable and active ORR electrocatalysts based on iron,an earth-abundant element.A core–shell zeolitic imidazolate framework–tannic acid coordination polymer composite(ZIF-8@K-TA)was utilized as the catalyst precursor,which was transformed into iron atoms dispersed in hollow porous nitrogen-doped carbon capsules(H-Fe-N_(x)-C)through ion exchange and pyrolysis.H-Fe-N_(x)-C fea-tures site-isolated single-atom iron centers coordinated to nitrogen in graphitic layers,high levels of nitrogen doping,and high permeability to incoming gases.Benefiting from these characteristics,H-Fe-N_(x)-C demonstrated efficient electrocatalytic activity(E_(1/2)=0.92 V,vs.RHE)and stability towards the ORR in both alkaline and acidic media.In ORR performance,it surpassed the majority of recently reported Fe-N-C catalysts and the standard Pt/C catalyst.In addition,H-Fe-N_(x)-C showed outstanding tolerance to methanol.展开更多
基金support from National Key Research and Development Program of China(No.2021YFF0500600)National Nat-ural Science Foundation of China(Nos.U2001220,51902223,and 51872195)+1 种基金Innovative Research Group Project of the National Natural Science Foundation of China(22121004)the Haihe Laboratory of Sustainable Chemical Transformations(YYJC202108).
文摘Solid-state lithium batteries are flourishing due to their excellent potential energy density.Substantial efforts have been made to improve their electrochemical performance by increasing the conductivity of solid-state electrolytes(SEs)and designing a compatible battery configuration.The safety of a solid lithium battery has generally been taken for granted due to the nonflammability and strength of SEs.However,recent results have shown the release of dangerous gases and intense heat due to the formation of lithium dendrites,indicating the safety of solid-state lithium batteries may have been overestimated.In this review,we introduce a safety evaluation methodology,then focus on the garnet Li_(7)La_(3)Zr_(2)O_(12)(LLZO)and sulfide-based SEs,summarizing their structure,conductivity,compatibility with a lithium metal anode,electrochemical/chemical stability,and mechanical/thermal stability,which correlate closely with battery safety.We also evaluate the safety of all-solid-state lithium batteries,then conclude by discussing future avenues for improving the safety of SE-based batteries.
基金supported by the National Natural Science Foundation of China(Grant No.51874362,51932011).
文摘The development of low-cost and eco-friendly gel polymer electrolytes (GPEs) with a wide window, ideal compatibility, and structural stability is an effective measure to achieve safe high-energy-density lithium-metal batteries. Herein, a biodegradable composite polyacrylonitrile/poly-L-lactic acid nanofiber membrane (PAL) is synthesized and used as a robust skeleton for GPEs. The 3D nanofiber membrane (PAL-3-C12) prepared with an adjusted weight ratio of polyacrylonitrile (PAN)/poly-L-lactic acid (PLLA) and spinning solution concentration delivers decent thermal stability, biodegradability, and liquid electrolyte absorbability. The “passivation effect” of PAN upon lithium metal is effectively alleviated by hydrogen bonds formed in the PAL chains. These advantages enable PAL GPEs to work stably to 5.17 V while maintaining high ionic conductivity as well as excellent corrosion resistance and dielectric properties. The interfacial compatibility of optimized GPEs promotes the stable operation of a Li||PAL-3-C12 GPEs||Li symmetric battery for 1000 h at 0.15 mA cm^(−2)/0.15 mA h cm^(−2), and the LiFePO4 full cell retains capacity retention of 97.63% after 140 cycles at 1C.
基金S.J.Bai,H.R.Qiu,and M.M.Song contributed equally to this work.This work is supported by the Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China(No.51888103).We also thank C.Liao for drawing some pictures for this article.In addition,we thank Doc.N.Deng and Miss D.He at the Instrumental Analysis Center of Xi'an Jiaotong University for their assistance with GC-MS and TRPL measurement.
文摘Solar-driven CO_(2)conversion to chemical fuels in an aqueous solution is restricted not only by photocatalysts but also by mass transfer.Here,a regulatable three-phase interface on a porous fixed-bed is constructed for efficient C-C coupling in photocatalytic CO_(2)reduction.The photocatalytic results show that∼90%selectivity towards C^(2+)products is obtained by a Cu/Cd_(0.5)Zn_(0.5)S photocatalyst,with a yield of 6.54μmol/h(an irradiation area of 0.785 cm^(2)),while only 0.94μmol/h(an irradiation area of 19.625 cm^(2))is achieved with a commonly used suspension photocatalytic reactor.We find that under the same CO_(2)feed rate,the local CO_(2)concentration in this porous fixed-bed photoreactor is obviously higher than in the suspension photoreactor.The larger local CO_(2)coverage derived from a higher CO_(2)supply and aggregation enhances the C-C coupling,thereby generating more C^(2+).Even an observable three-phase interface on the porous fixed-bed can be regulated by adjusting the CO_(2)supply,for which the optimal gas inlet rate is 5-10 sccm.
基金This work was financially supported by the NSFC(Nos.22225109,22071109,22105080 and 22201083)the Project funded by the China Postdoctoral Science Foundation(Nos.2020M682747 and 2021M701270)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(Grant 2023A1515010779 and 2023A1515010928)the Guangzhou Basic and Applied Basic Research Fund Project(Grant 202102020209)China National Postdoctoral Program for Innovative Talents(BX20220115).
文摘Electrocatalytic CO_(2) reduction(ECR)to high value-added chemicals by using renewable electricity presents a promising strategy to realize“carbon neutrality”.However,the ECR system is still limited by its low current density and poor CO_(2) utilization efficiency.Herein,by using the confinement effect of covalent organic frame-works(COFs)to confine the in-situ growth of metal nanoclusters(NCs),we develop a series of Cu NCs encap-sulated on COF catalysts(Cu-NC@COF)for ECR.Among them,Cu-NC@CuPc-COF as a gas diffusion electrode(GDE)achieves a maximum CO_(2)-to-CH_(4) Faradaic efficiency of 74±3%(at-1.0 V vs.Reversible Hydrogen Electrode(RHE))with a current density of 538±31 mA cm^(-2)(at-1.2 V vs.RHE)in a flow cell,making it one of the best among reported materials.More importantly,the current density is much higher than the relevant industrial current density(200 mA cm^(-2)),indicating the potential for industrial application.This work opens up new possibilities for the design of ECR catalysts that utilize synergistic strategy.
基金This work was supported by the NSFC(Grant 51861145101,21777096,22025505)Program of Shanghai Academic Technology Research Leader(Grant 20XD1422200)+1 种基金Cultivating fund of Frontiers Science Center for Transformative Molecules(2019PT02)China Postdoctoral Science Foundation(2020M671110).
文摘The efficiency and stability of typical three-dimensional(3D)MAPbI_(3)perovskite-based solar cells are highly restricted,due to the weak interaction between methylammonium(MA^(+))and[PbI 6]4-octahedra in the 3D structure,which can cause the ion migration and the related defects.Here,we found that the in situ-grown perovskitoid TEAPbI_(3)layer on 3D MAPbI_(3)can inhibit the MA^(+)migration in a polar solvent,thus enhancing the thermal and moisture stability of perovskite films.The crystal structure and orientation of TEAPbI_(3)are reported for the first time by single crystal and synchrotron radiation analysis.The ultra-thin perovskitoid layer can reduce the trap states and accelerate photo-carrier diffusion in perovskite solar cells,as confirmed by ultra-fast spectroscopy.The power conversion efficiency of TEAPbI_(3)-MAPbI_(3)based solar cells increases from 18.87%to 21.79%with enhanced stability.This work suggests that passivation and stabilization by in situ-grown perovskitoid can be a promising strategy for efficient and stable perovskite solar cells.
基金The authors acknowledge the support by National Natural Science Foundation of China(51871133)Taishan Scholar Foundation of Shan-dong Province,the Key Research and Development Program of Shandong Province(2021ZLGX01)the program of Jinan Science and Tech-nology Bureau(2019GXRC001).
文摘Magnesium-ion batteries(MIBs)are promising alternatives to lithium-ion batteries due to their safety and high theoretical specific capacity,and the abundance of magnesium reserves.However,their anodes and electro-lytes severely restrict the development of MIBs,so alloy-type anodes provide an effective strategy to circum-vent the surface passivation issue encountered with Mg metal in conventional electrolytes.Theoretically,a germanium anode can deliver a high specific capacity of 1476 mAh g?1,but hitherto,no experimental reports have described Ge in MIBs.Herein,we experimentally verified that Ge could reversibly react with Mg 2þions through the design of dual-phase Ge–Bi film electrodes fabricated by magnetron co-sputtering.Notably,a Ge 57 Bi 43 electrode delivered a high specific capacity of 847.5 mAh g?1,owing to the joint alloying reactions of Ge and Bi with Mg,which was much higher than the specific capacity of Bi(around 385 mAh g?1).Moreover,the Ge–Bi anode showed excellent rate performance,good cycling stability,and superior compatibility with conventional electrolytes such as Mg(TFSI)2.More importantly,the Mg storage mechanism of the Ge–Bi anode was unveiled by operando X-ray diffraction,and density functional theory calculations rationalized that the introduction of Bi to form Ge–Bi evidently decreased the defect formation energy and effectively boosted the electrochemical reactivity of Ge with Mg.
文摘Molten ZnCl_(2)hydrates are ionic liquids at room temperature,which exhibit intriguing physical and electrochemical properties.Continuous efforts have been devoted over several decades to understanding the properties of the molten ZnCl_(2)hydrates that have been dubbed as water-in-salt electrolytes recently.The physical properties of molten ZnCl_(2)hydrates can be described from the perspectives of ions in their speciation and water molecules regarding their chemical environments.Recently,attention has been given to molten ZnCl_(2)hydrates as electrolytes for Zn metal batteries.It was revealed that the physical properties of such electrolytes have rich implications in their electrochemical properties.Therefore,it demands a holistic understanding of the physical and electrochemical properties of molten ZnCl_(2)hydrates to design functional electrolytes to serve high-performing Zn metal batteries.This perspective attempts to review the works that described the properties of concentrated ZnCl_(2)as an ionic liquid and as an emerging electrolyte.The author also provides a perspective to highlight the needs of future research to circumvent the limits of this electrolyte.
基金supported by National Natural Science Foundation of China(Grant No.52002094,22479037)Guangdong Basic and Applied Basic Research Foundation(Grant No.2019A1515110756)+2 种基金Shenzhen Science and Technology Program(Grant No.JCYJ20210324121411031,JSGG202108021253804014,RCBS20210706092218040)the Shenzhen Steady Support Plan(GXWD20221030205923001,GXWD20201230155427003-20200824103000001)State Key Laboratory of Precision Welding&Joining of Materials and Structures(Grant Nos.24-Z-17,24-T-08).
文摘The Li-O_(2) battery(LOB)has attracted growing interest,including for its great potential in next-generation energy storage systems due to its extremely high theoretical specific capacity.However,a series of challenges have seriously hindered LOB development,such as sluggish kinetics during the oxygen reduction and oxygen evolution reactions(ORR/OER)at the cathode,the formation of lithium dendrites,and undesirable corrosion at the lithium metal anode.Herein,we propose a strategy based on the ultra-low loading of atomic Ni catalysts to simultaneously boost the ORR/OER at the cathode while stabilizing the Li metal anode.The resultant LOB delivers a superior discharge capacity(>16,000 mAh g^(-1)),excellent long-term cycling stability(>200 cycles),and enhanced high rate capability(>300 cycles@500 mA g^(-1)).The working mechanisms of these atomic Ni catalysts are revealed through carefully designed in situ experiments and theoretical calculations.This work provides a novel research paradigm for designing high-performance LOBs that are useable in practical applications.
基金supported by the Natural Science Foundation of Fujian Province,China(2021J06001)National Natural Science Foundation of China(22372072)National Key Research and Development Program of China(2020YFB1505800).
文摘With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention for their energy density,safety,and low cost,but problems with the zinc anode—such as hydrogen evolution,corrosion,passivation,dendrite proliferation,and deformation—have led to zinc–air batteries with low Coulombic efficiency and short cycle life;these remain the key obstacles hindering the batteries’further development.In this review paper,we briefly describe the reaction mechanism of zinc–air batteries,then summarize the strategies for solving the key issues in zinc anodes.These approaches are divided into three aspects:structural designs for the zinc anode;interface engineering;and electrolyte selection and optimization.We finish by offering some suggestions for future research directions to improve the zinc anode in zinc–air batteries.
基金supported by the National Natural Science Foundation(NSFC)of China(52002394)Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020006).
文摘The anionic redox reaction(ARR)is a promising charge contributor to improve the reversible capacity of layeredoxide cathodes for Na-ion batteries;however,some practical bottlenecks still need to be eliminated,including a low capacity retention,large voltage hysteresis,and low rate capability.Herein,we proposed a high-Na content honeycomb-ordered cathode,P2–Na_(5/6)[Li_(1/6)Cu_(1/6)Mn_(2/3)]O_(2)(P2-NLCMO),with combined cationic/anionic redox.Neutron powder diffraction and X-ray diffraction of P2-NLCMO suggested P2-type stacking with rarely found P6322 symmetry.In addition,advanced spectroscopy techniques and density functional theory calculations confirmed the synergistic stabilizing relationship between the Li/Cu dual honeycomb centers,achieving fully active Cu^(3+)/Cu^(2+) redox and stabilized ARR with interactively suppressed local distortion.With a meticulously regulated charge/discharge protocol,both the cycling and rate capability of P2-NLCMO were significantly.
基金supported by the National Natural Science Foundation of China(51972259,52172231 and U1804253)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHT2020-003)the Fundamental Research Funds for the Central Universities(WUT:2021III024GX,2021III001GL).
文摘Molybdenum-based materials have stepped into the spotlight as promising electrodes for energy storage systems due to their abundant valence states,low cost,and high theoretical capacity.However,the performance of conventional molybdenum-based electrode materials has been limited by slow diffusion dynamics and deficient thermodynamics.Applying defect engineering to molybdenum-based electrode materials is a viable method for overcoming these intrinsic limitations to realize superior electrochemical performance for energy storage.Herein,we systematically review recent progress in defect engineering for molybdenum-based electrode materials,including vacancy modulation,doping engineering,topochemical substitution,and amorphization.In particular,the essential optimization mechanisms of defect engineering in molybdenum-based electrode materials are pre-sented:accelerating ion diffusion,enhancing electron transfer,adjusting potential,and maintaining structural stability.We also discuss the existing challenges and future objectives for defect engineering in molybdenum-based electrode materials to realize high-energy and high-power energy storage devices.
基金support from the National Key Technology R&D Program of China(2022YFB3504302,2022YFC3-901503)Natural Science Foundation and Overseas Talent Projects of Jiangxi Province(20232BAB214025,20232BCJ25044)Self-deployed Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E355F003).
文摘Stabilizing the highly active RuO_(2) electrocatalyst for the oxygen evolution reaction(OER)is critical for the application of proton exchange membrane water electrolysis,but this remains challenging due to the inevitable over-oxidation of Ru in harsh oxidative environments.Herein,we describe constructing Ru-O-La asymmetric configurations into RuO_(2) via a facile sol-gel method to tailor electron redistribution and thereby eliminate the over-oxidation of Ru centers.Specifically,the as-prepared optimal La_(0.1)Ru_(0.9)O_(2) shows a low overpotential of 188 mV at 10 mA cm^(-2),a high mass activity of 251 A gRu^(-1) at 1.6 V vs.reversible hydrogen electrode(RHE),and a long-lasting durability of 63 h,far superior to the 8 h achieved by standard RuO_(2).Experiments and density functional theory calculations jointly reveal that the Ru-O-La asymmetric configuration could trigger electron redistribution in RuO_(2).More importantly,electron transfer from La to Ru via the Ru-O-La configuration could lead to increased electron density around Ru,thus preventing the over-oxidation of Ru.In addition,electron redistribution tunes the Ru 4d band center’s energy level,which optimizes the adsorption and desorption of oxygen intermediates.This work offers an effective strategy for regulating electronic structure to synergistically boost the activity and stability of RuO_(2)-based acidic OER electrocatalysts.
基金supported by the National Key Research and Development Program of China(2022YFE0138900)the National Natural Science Foundation of China(21972017)the“Scientific and Technical Innovation Action Plan”Basic Research Field of Shanghai Science and Technology Committee(19JC1410500).
文摘Regulating the pore structure of a zirfon-based diaphragm is critical to promoting a high-rate alkaline electrolyzer,but it is still a big challenge to respond“trade-off”between the thickness of the diaphragm and the current density/gas barrier behavior.In this work,a porous hydrophilic skin layer with~μm thick of polyvinyl alcohol(PVA)has been successfully constructed and casted onto the thin zirfon-type separator composite(V-Zirfon-350μm).The V-Zirfon-350μm separator generates a high KOH uptake(>90%),low area resistance(0.2026Ωcm^(2))but a low electrolyte permeation flux density(5.2×10^(-4) mL cm^(-2) s^(-1) at 0.5 bar),which largely surpasses the state-of-the-art commercial Zirfon UTP-500μm diaphragm.When coupled with Raney Ni cathode and NiCoMo-LDH anode catalysts,the V-Zirfon-350μm separator offers a high current density over 1300 mA cm^(-2)@2.0 V(80℃ in 30%KOH)and a superior stability of 300 h under 800 mA cm^(-2) for alkaline water electrolysis(AWE).Specifically,the voltage is merely~3.5 V for two electrolytic cells connected in series,which can be even conducted for more than 1300 h at different operational conditions.This work provides a novel methodology for the practical application of a thin Zirfon-based diaphragm.
基金gratefully express gratitude to all parties who have contributed toward the success of this project,both financially and technically,especially the S&T Innovation 2025 Major Special Programme(Grant No.2018B10022)the Ningbo Commonweal Programme(Grant No.2022S122)funded by the Ningbo Science and Technology Bureau,China,as well as the UNNC FoSE Faculty Inspiration Grant,China+1 种基金the support from the Ningbo Municipal Key Laboratory on Clean Energy Conversion Technologies(2014A22010)as well as the Zhejiang Provincial Key Laboratory for Carbonaceous Wastes Processing and Process Intensification Research funded by the Zhejiang Provincial Department of Science and Technology(2020E10018)support from the ANU Futures Scheme(Q4601024).
文摘Achieving carbon neutrality is an essential part of responding to climate change caused by the deforestation and over-exploitation of natural resources that have accompanied the development of human society.The carbon dioxide reduction reaction(CO_(2)RR)is a promising strategy to capture and convert carbon dioxide(CO_(2))into value-added chemical products.However,the traditional trial-and-error method makes it expensive and time-consuming to understand the deeper mechanism behind the reaction,discover novel catalysts with superior performance and lower cost,and determine optimal support structures and electrolytes for the CO_(2)RR.Emerging machine learning(ML)techniques provide an opportunity to integrate material science and artificial intelligence,which would enable chemists to extract the implicit knowledge behind data,be guided by the insights thereby gained,and be freed from performing repetitive experiments.In this perspective article,we focus on recent ad-vancements in ML-participated CO_(2)RR applications.After a brief introduction to ML techniques and the CO_(2)RR,we first focus on ML-accelerated property prediction for potential CO_(2)RR catalysts.Then we explore ML-aided prediction of catalytic activity and selectivity.This is followed by a discussion about ML-guided catalyst and electrode design.Next,the potential application of ML-assisted experimental synthesis for the CO_(2)RR is discussed.
基金supported by the National Natural Science Foundation of China(21875026,21878031)the Program for Liaoning Excellent Talents in University(LR2014013)+2 种基金the Science and Technology Foundation of Liaoning Province(No.201602052)the Natural Science Foundation of Liaoning Province(No.20170520427)by the Liaoning Revitalization Talents Program(XLYC1802124).
文摘Devising a desirable nano-heterostructured photoelectrode based on the charge transfer kinetics mechanism is a pivotal strategy for implementing efficient photoelectrocatalytic(PEC)technology,since the charge separation and utilization efficiency of a photoelectrode is critical to its PEC performance.Herein,we fabricate a F–Co_(3)O_(4)@Bi_(2)WO_(6) core–shell hetero-array photoanode by coupling Bi_(2)WO_(6) nanosheets with F–Co_(3)O_(4) nanowires using a simple solvothermal solution method.The three-dimensional hierarchical heterostructure has a homogeneous chemical interface,helping it to promote an S-scheme-based carrier transport kinetics and maintain excellent cycling stability.Charge density difference calculations verify the electron migration trend from F–Co_(3)O_(4) to Bi_(2)WO_(6) upon hybridization and the formation of an internal electric field in the heterojunction,consistent with the S-scheme mechanism,which is identified by in situ irradiation X-ray photoelectron spectroscopy and by ultraviolet photoelectron spectroscopy.The optimized F–Co_(3)O_(4)@Bi_(2)WO_(6)-2 photoelectrode achieves high carrier utilization efficiency and exhibits superior PEC degradation performance for various organic pollutants,including reactive brilliant blue KN-R,rhodamine B,sulfamethoxazole,and bisphenol A.This work not only reveals that F–Co_(3)O_(4)@Bi_(2)WO_(6)-2 is effective for PEC water remediation but also provides a strategy to enhance carrier transport kinetics by designing binary oxides.
基金financially supported by the National Natural Science Foundation of China(No.22209106)Shanghai Pujiang Program(21PJ1408700)+1 种基金the National Key Research and Development Program of China(2022YFB2402300)supported by the Assistant Secretary for Energy Efficiency and Renewable Energy(EERE),Vehicle Technology Office(VTO)of the US Department of Energy(DOE)through the Advanced Battery Materials Research(BMR)Program under contract no.DE-SC0012704.
文摘The conventional perspective suggests that low-concentration electrolytes(LCEs)face challenges in achieving stable charge/discharge properties due to the decreased ionic conductivity resulting from lower Li^(+) concentrations.However,the successful utilization of LCEs in lithium/sodium-ion batteries has brought them into the forefront of consideration for high performance battery systems.It is possible to achieve improved interface stability and ion transport performance for LCEs through adjusting electrolyte components,such as salts,solvents,and additives.This review provides timely update of the recent research progress,design strategies and remaining challenges of LCEs to answer several questions:i)What is the key factor for designing LCEs?ii)How to balance the low salt concentration and good ionic conductivity?iii)What is the interphasial mechanism of anode/cathode in LCEs?Firstly,the development of LCEs is discussed with typical examples.Subsequently,effectiveness of solvents on overall performances of LCEs is comprehensively summarized in detail.Finally,the challenges and possible research direction of LCEs are discussed.This review provides critical guidance for designing novel electrolytes for secondary batteries.
文摘Energy is always closely correlated with the development of human society.Today,energy demand is growing rapidly,causing excessive CO_(2)emissions that are contributing to global warming and extreme weather events.From industrial civilization to ecological civilization,the utilization of energy requires more environmentally friendly technologies,especially if we are to achieve the global goal of carbon neutrality.
基金This work is financially supported by National Natural Science Foundation of China(11974063)Fundamental Research Funds for the Central Universities(2022CDJQY-010)+1 种基金Graduate scientific research and innovation foundation of Chongqing,China(No.CYB22060)Fundamental Research Funds for the Central Universities(2021CDJQY-022).The authors would like to thank Dr.Xiangnan Gong and Miss Chuanyao Yang at Analytical and Testing Center of Chongqing University for their assistance with SCXRD and PL analysis.The authors would also like to thank Kang An(Industrial Computed Tomography(ICT)Research Center of Chongqing University)and Qianqian Lin(School of Physics and Technology of Wuhan University)for their assistance with X-ray images of scintillators。
文摘Low-dimensional luminescent lead-free metal halides have received substantial attention due to their unique optoelectronic properties.Among them,zero-dimensional(0D)manganese(II)-based metal halides with negligible self-absorption have emerged as potential candidates in X-ray scintillators.Herein,we for the first time report a novel lead-free(TBA)_(2)MnBr_(4) single crystal synthesized via a facile solvent evaporation method.In this crystal,[MnBr_(4)]^(2-)units are isolated by large TBA^(+)organic cations,resulting in a unique 0D structure.The prepared manganese-based crystals exhibit a bright-green emission centered at 512 nm with a high photoluminescence quantum yield(PLQY)of 93.76%at room temperature,originating from the ^(4)T_(1)–^(6)A_(1) transition of Mn^(2+).Apart from their outstanding optical performance,the crystals also show excellent stability and can maintain 94.4%of the initial PLQY even after being stored in air for 90 days.Flexible(TBA)_(2)MnBr4 films prepared as X-ray imaging scintillators exhibit a low detection limit of 63.3 nGyair/s,a high light yield of 68000 ph/MeV,and a high spatial resolution of 15.4 lp/mm.Thus,this work not only enriches the family of lead-free metal halides but also expands the application of manganese(II)-based halides in flexible X-ray scintillators.
基金supported by the National Natural Science Foundation of China(Nos.12064047,11864044,11704330,and 11564043)the Key and General Program of Yunnan Fundamental Research Projects(Nos.202101AS070046 and 202001BB050051)The model software in this work is the Device Studio software package from Hongzhiwei.
文摘Layer-number modulation in graphene has become a recent focus of research due to the superior degree of freedom that can be achieved in terms of magic-angle,wettability,superconductivity,and superlattices.However,the intrinsic transport of multilayer graphene is indistinguishable in atmospheric adsorbates and supporting environment,and its underlying charge transfer mechanism has not yet been thoroughly determined.In this study,a shift in the charge neutrality point of trilayer graphene(TLG)is demonstrated to be regulated by three governing factors:oxygen gas(O_(2)),water molecules(H_(2)O),and thermally activated electrons.Absorbed O_(2) induces a high work function in semimetallic TLG,while H_(2)O is not an evident dopant but can strengthen binding against O_(2) desorption.A simplified model is developed to elucidate the competitive mechanism and charge transfer among these two dopants(O_(2),H_(2)O)and thermal electrons,and the model is demonstrated by work function regulation and Bader charge transfer based on density functional theory calculations.This study provides a strategy to explore transport modulation of multilayer graphene in the fields of ballistic transport and low power consumption of graphene field-effect transistors.
基金Foundation(B?0027)(SM),National Science Foundation of China(Grants 22006036)North China Electric Power University(XM2112307)(HY and XW)+1 种基金GINW is supported by a James Cook Research Fellowship from New Zealand Government funding,administered by the Royal Society Te Aparangisupport from the XAS beamline scientists of the Australian Synchrotron and the 14 W station of the Shanghai Synchrotron Radiation Facility(SSRF).
文摘The large-scale synthesis of platinum-free electrocatalysts for the oxygen reduction reaction(ORR)remains a grand challenge.We report the large-scale production of stable and active ORR electrocatalysts based on iron,an earth-abundant element.A core–shell zeolitic imidazolate framework–tannic acid coordination polymer composite(ZIF-8@K-TA)was utilized as the catalyst precursor,which was transformed into iron atoms dispersed in hollow porous nitrogen-doped carbon capsules(H-Fe-N_(x)-C)through ion exchange and pyrolysis.H-Fe-N_(x)-C fea-tures site-isolated single-atom iron centers coordinated to nitrogen in graphitic layers,high levels of nitrogen doping,and high permeability to incoming gases.Benefiting from these characteristics,H-Fe-N_(x)-C demonstrated efficient electrocatalytic activity(E_(1/2)=0.92 V,vs.RHE)and stability towards the ORR in both alkaline and acidic media.In ORR performance,it surpassed the majority of recently reported Fe-N-C catalysts and the standard Pt/C catalyst.In addition,H-Fe-N_(x)-C showed outstanding tolerance to methanol.
