查看更多>>摘要：Prussian blue analogues(PBAs)are regarded as promising cathode materials for potassium-ion batteries(PIBs)owing to their low cost and high reversible capacity.Compared to other PBAs,potassium manganese hexacyanoferrate(KMnHCF)stands out for its superior capacity and operating voltage.However,Jahn-Teller effect of Mn3+and the structural collapse caused by potassium ion insertion/extraction still affect the structural stability and electrochemical performance of this material.Herein,a green and efficient synthesis method is adopted to substitute potassium ions in KMnHCF with an appro-priate amount of cesium ions to form a column effect.Cesium-doped KMnHCF(Cs-KMnHCF)mitigates the irreversible structural damage caused by potassiation/depotassiation and the Jahn-Teller effect,thereby improving the cycling stability.In addition,it widens the lattice channels,reduces the diffusion barrier of potassium ions,and optimizes the diffusion kinetics.By rationally controlling the doping amount of Cs+,the obtained K1.71Cs0.0sMn[Fe(CN)6]0.95-0.05·0.88H2O exhibits remarkable electrochemical performance,with an initial discharge capacity of 137.6 mA h g-1 at a current density of 20 mA g-1 and a capacity retention of 89.6％after 600 cycles at 200 mA g-1.More importantly,when assembled with a pitch-derived soft carbon anode,the full cell manifests excellent cycle stability and rate performance.This work is expected to provide a highly efficient cathode material for the practical application of PIBs.
查看更多>>摘要：As the global electric vehicle market continues to grow,the recycling of Li-ion battery(LIB)becomes more important worldwide and the resynthesis of cathode materials would be the most value-added recycling approach taking into account limited metal resources.Although resynthesized homogenous LiNixCoyMnzO2(NCM)from spent LIB leachate shows comparable battery performance to pristine NCM from virgin materials,there is general concern in its cycling performance.Here,we synthesize core-shell(CS)Ni-rich NCM,which consists of Ni-rich NCM as the core and NCM derived from the original or puri-fied leachate of spent LIBs as the shell.Resynthesized CS Ni-rich NCM exhibits improved rate capability resulting from expanded interslab thickness in the NCM structure.CS Ni-rich NCM from purified LIB lea-chate shows improvement in cycling performance and thermal stability.It specifically delivers a capacity retention of 86.6％at a high temperature after 80 cycles compared to that(75.0％)of pristine CS Ni-rich NCM.These improvements are caused by a relatively high Mg content on the shell and the widespread distribution of Al through the CS structure.CS Ni-rich NCM derived from spent LIB leachate provides a new alternative approach to conventional LIB recycling methods,which would utilize efficiently limited metal resources for the sustainable LIB production.
查看更多>>摘要：Zn powder anodes have attracted much attention in aqueous Zn ion battery applications due to advan-tages such as low cost and processability.However,the high-activity Zn powder anode faces problems such as side reactions,hydrogen evolution,and dendrites,which limit the cycling stability of the cell.In this work,the high activity of Zn powder is weakened by introducing low-cost erythritol as a functional additive in the ZnSO4 electrolyte to improve the cycle life of the cell.Both theoretical calculations and empirical evidence demonstrate that the incorporation of erythritol alters the coordination sphere of Zn2+and modifies the local molecular architecture of the electrolyte.This modification serves to diminish the reactivity of water molecules,thereby efficaciously suppressing dendrite formation and deleterious ancillary reactions on the zinc powder anode surfaces.Concurrently,erythritol functions as an interfacial cationic captor,enhancing reaction dynamics and facilitating the development of a favorable protective layer throughout the zinc plating/stripping process.Consequently,the symmetric cell paired with an erythritol-containing electrolyte manifests stable cycling performance for an extended duration of 850 h at a current density of 0.288 mA cm-2 and areal capacity of 0.144 mAh cm-2.Notably,it maintains a cycling life of 400 h even under intensified conditions(2.88 mA cm-2/1.44 mA h cm-2).Furthermore,the constructed Na2V6O16·3H2O full cell illustrated remarkable capacity retention of 155.8 mA h g-1 following 800 cycles at a high rate of 5 A g-1.
查看更多>>摘要：In the exploration of next-generation high-energy-density batteries,lithium metal is regarded as an ideal candidate for anode materials.However,lithium metal batteries(LMBs)face challenges in practical appli-cations due to the risks associated with organic liquid electrolytes,among which their low flash points are one of the major safety concerns.The adoption of high flash point quasi-solid polymer electrolytes(QSPE)that is compatible with the lithium metal anode and high-voltage cathode is therefore a promising strategy for exploring high-performance and high-safety LMBs.Herein,we employed the in-situ polymer-ization of poly(epoxidized soya fatty acid Bu esters-isooctyl acrylate-ditrimethylolpropane tetraacrylate)(PEID)to gel the liquid electrolyte that formed a PEID-based QSPE(PEID-QSPE).The flash point of PEID-QSPE rises from 25 to 82 ℃ after gelation,contributing to enhanced safety of the battery at elevated tem-peratures,whereas the electrochemical window increases to 4.9 V.Moreover,the three-dimensional polymer framework of PEID-QSPE is validated to facilitate the uniform growth of the solid electrolyte interphase on the anode,thereby improving the cycling stability of the battery.By employing PEID-QSPE,the Li|LiNi0.9Co0.05Mn0.05O2 cell achieved long-term cycling stability(Coulombic efficiency,99.8％;＞200 cycles at 0.1 C)even with a high cathode loading(～5 mg cm-2)and an ultrathin Li(～50 μm).This electrolyte is expected to afford inspiring insights for the development of safe and long-term cyclability LMBs.
查看更多>>摘要：High-temperature polymer electrolyte membrane fuel cells(HT-PEMFCs)show excellent application pro-spects due to its enhanced tolerance of hydrogen impurity.However,the sluggish electrode kinetics caused by its inefficient electrocatalytic interface and proton transfer severely restricts its performance.To overcome the sluggish electrode kinetics,the ethylenediamine tetramethylenephosphonic acid(EDTMPA)was successfully incorporated into the catalysts layer to regulate the phosphoric acid(PA)dis-tribution to boost the electrocatalytic reaction interface and proton transfer,thus increasing the output power and stability of HT-PEMFCs.The hydrophilic H2PO4-and electron donor N atom of EDTMPA could efficiently decrease the absorption of PA on the catalyst surface and facilitate proton transportation in the membrane electrode,as demonstrated by our experiments.The fuel cell assembled with the prepared membrane electrode shows a high reactivity of 1175 mW cm-2 and excellent stability,which is much better than the past reference report.The results of this work provide new insights into the utilization of small molecules with phosphate groups to enhance phosphate tolerance and proton conduction,and there is also a further improvement in the reactivity,durability,and utilization of the electrocatalysts in HT-PEMFCs.
查看更多>>摘要：Nonfullerene organic solar cells(OSCs)and photodetectors have received tremendous interest due to their rapidly progressed power conversion efficiency(PCE)and wide range photoresponse to near-infrared region,respectively.Further optimization of the interfacial transport layer is one of the key fac-tors toward enhanced performance.Herein,we reported a general multi-component electron transport layer(ETL)strategy to achieve better energy level alignments and interfacial contact for both OSCs and photodetectors.The binary polymer:molecule blend based ETL can overcome low crystallinity and self-aggregation issue in neat polymer and molecule ETL,respectively.The mixed blend provides a more tun-able platform to optimize the interfacial morphology and creates more efficient charge-transporting pathways.We showcase that the PNDIT-F3N:PDINN binary ETL exhibits its strength in a series of non-fullerene OSCs with enhanced fill factor and current density,achieving a champion PCE approaching 19％.Additionally,self-powered organic photodetectors with lower dark current and high detectivity were achieved with the same binary ETL strategy.Detailed morphology and device characterizations reveal that the binary ETL modulates the interfacial interface to deliver a more favorable energy level alignment,facilitating carrier extraction and transport.We believe these findings could provide insight into the design of ETL with sufficient interfacial tunability for organic optoelectronic devices.
查看更多>>摘要：Aqueous zinc metal batteries(AZMBs)are hindered by uncontrolled dendrites and side reactions during commercialization,despite their advantages of safety and high capacity density.Herein,we propose the electrical feedback strategy to restrain the Zn dendrites resulting from the"tip effect"and optimize inter-facial Zn2+distribution to accelerate electrodeposition kinetics by using the lithium niobate(LNO)layer.Specifically,at the bumps of the zinc anode,the ferroelectric LNO is polarized by the locally strong elec-tric field,which in turn counteracts the"tip effect".In this way,the dynamic polarization of LNO can repair the uneven tip electric field to achieve uniform and flat zinc deposition.In addition,owing to the interaction between Nb and Zn2+,a higher concentration of Zn2+near the zincophilic LNO@Zn surface is obtained for the rapid electrochemical reaction kinetics of plating.Considering the aforementioned advantages,the LNO@Zn anode harvests stable cycling over 1200 h at 10 mA cm-2 with a superior cumu-lative capacity of 5800 mAh cm-2.Assembled with the α-MnO2 cathode,the full cell using LNO@Zn anode exhibits the slower capacity decay(0.054％per cycle)during 1000 cycles.This strategy provides a per-spective for stabilizing zinc metal anodes through dynamic electrical response and interfacial ion redis-tribution effect.
查看更多>>摘要：Ammonia decomposition is a key reaction in the context of hydrogen storage,transport,and release.This study combines density functional theory(DFT)calculations with microkinetic modeling to address the promotion mechanism of Ba species for ammonia decomposition on Co catalysts.The modified adsorp-tion properties of Co upon the addition of metallic Ba or BaO suggest that the promoters play a role in alleviating the competitive adsorption of H.Calculating the full reaction pathway of ammonia decompo-sition shows that limiting the investigation to the N-N association step,as done previously,overlooks the effect of the promoter on the energy barriers of the NHx dehydrogenation steps.Challenges of modeling the ammonia decomposition reaction are addressed by understanding that the NH2 intermediate is sta-bilized on the step sites rather than the terrace sites.When the effect of H-coverage on the adsorption of NH3 is not considered in the microkinetic simulations,the results conflict with the experiments.However,accounting for the effect of H-coverage,as performed here,shows that BaO-doped Co has higher rates than pristine Co and Ba-doped Co at the reaction temperature of 723.15 K.When H is adsorbed on the Ba-doped Co,the adsorption of ammonia becomes significantly endergonic,which makes the rates relatively slow.The superiority of the BaO-promoted catalyst is attributed to a lower energy for the transition state of the rate-determining step,coupled with a reduced impact of the hydro-gen coverage on weakening the ammonia adsorption.The kinetic analysis of the influence of Ba and BaO on the Co surface shows that BaO-doped Co aligns more closely with experimental observations than Ba-doped Co.This implies that Ba on the Co surface is likely to be in an oxide form under reaction conditions.Understanding the kinetics of the ammonia decomposition reaction provides a foundation for developing highly effective catalysts to accelerate the industrial utilization of ammonia as a sustainable hydrogen carrier.
查看更多>>摘要：The well-developed multifunctional wearable electronic device has fed the demand for human medicine and health monitoring in complex situations.However,the advancement of nuclear technology,espe-cially irradiation medicine and safety inspections,has increased the exposure risk of irradiation safety workers.Traditional irradiation detectors are stiff and incompatible with the skin,and lack human health monitoring function,thus it's vital to apply these flexible sensors for irradiation warning.Here,we report a novel composite gel device synthesized through solution processes by combining the Cs3Cu2I5:Zn nano-scintillator with the pre-patterned biocompatible gel,exhibiting a bi-functional response to motion/vibration sensing and sensitive irradiation warning.These wearable devices achieve a pressure sensitivity of up to 34 kPa-1 in a low-pressure range(0-3 kPa),a low limit of detection(LoD)down to 1.4 Pa,enabling health monitoring functions of pulse monitoring,finger bending,and elbow bending.Simultaneously,the device scintillates under X-ray irradiation among a wide dose rate range of 54-1167 μGyair s-1.The robust device shows no obvious signal loss after 4000 compression cycles and also excellent irradiation resistance over 50 days,broadening the path for designing and realizing new func-tional wearable devices.
查看更多>>摘要：Electrocatalytic reduction of CO2 is crucial for environmental sustainability and renewable energy stor-age,with Cu-based catalysts excelling in producing high-value C2+products.However,a comprehensive analysis of how specific electrolyte influences Cu-based catalysts is lacking.This review addresses this gap by focusing on how electrolytes impact surface reconstruction and the CO2 reduction process on Cu-based electrocatalysts,identifying specific electrolyte compositions that enhance the density and sta-bility of active sites,and providing insights into how different electrolyte environments modulate the selectivity and efficiency of C2+product formation.The review begins by exploring how electrolytes induce favorable surface reconstruction in Cu-based catalysts,affecting surface roughness through dissolution-redeposition of Cu species and interactions with halogens and molecular additives.It also covers changes in crystalline facets of Cu and Cu2O,and oxidation states,highlighting transitions from Cu0 to Cuδ+and the stabilization of Cu+.The role of electrolytes in the C-C coupling process is examined,emphasizing their effects in modulating mass and charge transfer,CO2 adsorption,intermediate evolu-tion,and product desorption.Subsequently,the mechanisms by non-aqueous electrolytes,including organic solvents,ionic liquids,and mixed electrolytes,affecting CO2 reduction are analyzed,highlighting the unique advantages and challenges of each type.The review concludes by addressing current chal-lenges,proposing solutions,and research directions,such as optimizing electrolyte composition by inte-grating diverse cations and anions and employing advanced in-situ characterization techniques.These insights can significantly enhance CO2 reduction performance on Cu-based electrocatalysts,advancing efficient and sustainable green energy technologies.
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