查看更多>>摘要：Rechargeable battery cycling performance and related safety have been persistent concerns.It is crucial to decipher the capacity fading induced by electrode material failure via a range of techniques.Among these,synchrotron-based X-ray techniques with high flux and brightness play a key role in understanding degradation mechanisms.In this comprehensive review,we summarize recent advancements in degra-dation modes and mechanisms that were revealed by synchrotron X-ray methodologies.Subsequently,an overview of X-ray absorption spectroscopy and X-ray scattering techniques is introduced for charac-terizing failure phenomena at local coordination atomic environment and long-range order crystal struc-ture scale,respectively.At last,we envision the future of exploring material failure mechanism.
查看更多>>摘要：In this study,the hydrogel network was reinforced by covalent-like hydrogen bonding,and the strong binding ability of boron-nitrogen coordination served as the main driving force.Among them,acrylamide(AM)and 3-acrylamidophenylboronic acid(AAPBA)were the main body,and the numerous hydroxyl groups in the trehalose(Treh)molecule and other polymer groups formed strong hydrogen bonding interactions to improve the mechanical properties of the PAM/PAAPBA/Treh(PAAT)hydrogel and ensured the simplicity of the synthesis process.The hydrogel possessed high strain at break(1239％),stress(64.7 kPa),low hysteresis(100％to 500％strain,corresponding to dissipation energy from 1.37 to 7.80 kJ/m3),and outstanding cycling stability(retained more than 90％of maximum stress after 200 ten-sile cycles).By integrating carbon nanotubes(CNTs)into PAAT hydrogel(PAATC),the PAATC hydrogel with excellent strain response performance was successfully constructed.The PAATC conductive hydro-gel exhibited high sensitivity(gauge factor(GF)=10.58 and sensitivity(S)=0.304 kPa-1),wide strain response range(0.5％-1000％),fast response time(450 ms),and short recovery time(350 ms),excellent fatigue resistance,and strain response stability.Furthermore,the PAATC-based triboelectric nanogener-ator(TENG)displayed outstanding energy harvesting performance,which shows its potential for appli-cation in self-powered electronic devices.
查看更多>>摘要：Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ability.However,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na+redox process,leading to"voltage failure"and rapid capacity decay.Herein,a metal cobalt-doping vanadium disulfide(Co-VS2)is proposed to simulta-neously accelerate the electrochemical reaction of VS2 and enhance the bidirectional redox of soluble NaPSs.It is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS2 can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high reversibility.Moreover,Co-VS2 also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion kinetics.Therefore,the Co-VS2 anode exhibits ultrahigh rate capability(562 mA h g-1 at 5 A g-1),high initial coulombic efficiency(≈90％)and 12,000 ultralong cycle life with capacity retention of 90％in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg-1/31,250 W kg-1)and over 10,000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg-1 and exceed 600 stable cycles.This work deepens the understanding of the electrochem-ical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttling of NaPSs in SIBs and SIHCs.
查看更多>>摘要：Polymer solid electrolytes(SPEs)based on the[solvate-Li+]complex structure have promising prospects in lithium metal batteries(LMBs)due to their unique ion transport mechanism.However,the solvation structure may compromise the mechanical performance and safety,hindering practical application of SPEs.In this work,a composite solid electrolyte(CSE)is designed through the organic-inorganic syner-gistic interaction among N,N-dimethylformamide(DMF),polycarbonate(PC),and Mg2B2O5 in poly(vinyli-dene fluoride-co-hexafluoropropylene)(PVDF-HFP).Flame-retardant Mg2B2O5 nanowires provide non-flammability to the prepared CSEs,and the addition of PC improves the dispersion of Mg2B2O5 nanowires.Simultaneously,the organic-inorganic synergistic action of PC plasticizer and Mg2B2O5 nanowires pro-motes the dissociation degree of LiTFSI and reduces the crystallinity of PVDF-HFP,enabling rapid Li ion transport.Additionally,Raman spectroscopy and DFT calculations confirm the coordination between Mg atoms in Mg2B2O5 and N atoms in DMF,which exhibits Lewis base-like behavior attacking adjacent C-F and C-H bonds in PVDF-HFP while inducing dehydrofluorination of PVDF-HFP.Based on the syner-gistic coupling of Mg2B2O5,PC,and DMF in the PVDF-HFP matrix,the prepared CSE exhibits superior ion conductivity(9.78 × 10-4 S cm-1).The assembled Li symmetric cells cycle stably for 3900 h at a current density of 0.1 mA cm-2 without short circuit.The LFP||Li cells assembled with PDL-Mg2B2O5/PC CSEs show excellent rate capability and cycling performance,with a capacity retention of 83.3％after 1000 cycles at 0.5 C.This work provides a novel approach for the practical application of organic-inorganic synergistic CSEs in LMBs.
查看更多>>摘要：Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based elec-trolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetoni-trile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Li+sol-vates as temperature drops,maintaining the merits of fast Li+transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g-1 at-20 ℃).Remarkably,an extremely high capacity retention of 97％is achieved for high-voltage high-energy graphite||NCM batteries after 250 cycles at-20 ℃,and a high capacity of 110 mA h g-1(71％of its room-temperature capacity)is retained at-30 ℃.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.
查看更多>>摘要：Safety issue is still a problem nowadays for the large-scale application of lithium-ion batteries(LIBs)in electric vehicles and energy storage stations.The unsafe behaviors of LIBs arise from the thermal run-away,which is intrinsically triggered by the overcharging and overheating.To improve the safety of LIBs,various protection strategies based on self-actuating reaction control mechanisms(SRCMs)have been proposed,including redox shuttle,polymerizable monomer additive,potential-sensitive separator,thermal shutdown separator,positive-temperature-coefficient electrode,thermally polymerizable addi-tive,and reversible thermal phase transition electrolyte.As build-in protection mechanisms,these meth-ods can sensitively detect either the temperature change inside battery or the potential change of the electrode,and spontaneously shut down the electrode reaction at risky conditions,thus preventing the battery from going into thermal runaway.Given their advantages in enhancing the intrinsic safety of LIBs,this paper overviews the research progresses of SRCMs after a brief introduction of thermal runaway mechanism and limitations of conventional thermal runaway mitigating measures.More importantly,the current states and issues,key challenges,and future developing trends of SRCTs are also discussed and outlined from the viewpoint of practical application,aiming at providing insights and guidance for developing more effective SRCMs for LIBs.
查看更多>>摘要：Precision engineering of catalytic sites to guide more favorable pathways for Li2O2 nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of Li-O2 batteries.In this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N4 moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of Li-O2 batteries.The porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of Li2O2.The Li-O2 batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g-1 at 100 mA g-1),and superior cycle stability(＞100 cycles at 200 mA g-1)compared with the Mn NPs-NC and NC.Density functional theory(DFT)cal-culations reveal that the construction of Mn-N4 moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(LiO2 and Li2O2).The initial nucleation of Li2O2 on Mn SAs-NC favors the O2 → LiO2 → Li2O2 surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N4 moiety effectively facilitates the Li2O2 nucleation and enables its reversible decomposition.This work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for Li-O2 batteries.
查看更多>>摘要：Hybrid organic-inorganic perovskites(HOIPs)hold promise in the field of optoelectronics due to their excellent photoelectric conversion efficiency.However,the ion migration and hygroscopicity of these perovskite solar cells need to be addressed.Here,we presented semitransparent perovskite solar cells(ST-PSCs)using hole transport layer(HTL)combined with polyaniline(PANI)to stabilize HTL/perovskite interface,achieving a humidity durability(RH,50％-90％)for 596 days(14304 h)without encapsulation.Moreover,the decrease in hydrolysis products(LiF)showed the interaction between PANI with the addi-tives in HTL dramatically inhibited the water uptake and corrosion on MAPbI3 layer.The PANI modified samples had a higher I/Pb ratio and lower trap state density,which indicated the passivation effect of PANI on the uncoordinated Pb2+and iodine vacancies.Subsequently,PANI successfully stabilized the interface and perovskite by inhibiting the formation of Pb0 and Au migration as long period storage.This work presented an interfacial design to develop HOIP in air with high humidity stability.
Himangshu BaishyaRamkrishna Das AdhikariMayur Jagdishbhai PatelDeepak Yadav...
217-253页
查看更多>>摘要：The rapid advancement of halide-based hybrid perovskite materials has garnered significant research attention,particularly in the domain of photovoltaic technology.Owing to their exceptional optoelec-tronic properties,they demonstrated power conversion efficiency(PCE)of over 25％in single junction solar cells.Despite the notable progress in PCE over the past decade,the inherent high defect density pre-senting in perovskite materials gives rise to several loss mechanisms and associated ion migration in per-ovskite solar cells(PSCs)during operational conditions.These factors collectively contribute to a significant stability challenge in PSCs,placing their longevity far behind for commercialization.While numerous reports have explored defects,ion migration,and their impacts on device performance,a com-prehensive correlation between the types of defects and the degradation kinetics of perovskite materials and PSCs has been lacking.In this context,this review aims to provide a comprehensive overview of the origins of defects and ion migration,emphasizing their correlation with the degradation kinetics of per-ovskite materials and PSCs,leveraging reliable characterization techniques.Furthermore,these charac-terization techniques are intended to comprehend loss mechanisms by different passivation approaches to enhance the durability and PCE of PSCs.
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