查看更多>>摘要：The disparity in the transfer of carriers(electrons/mass)during the reaction in zinc-air batteries(ZABs)results in sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),along with elevated overpotentials,thereby imposing additional constraints on its utilization.Therefore,the pre-design and target-development of inexpensive,high-performance,and long-term stable bifunctional catalysts are urgently needed.In this work,an apically guiding dual-functional elec-trocatalyst(Ag-FeNx-N-C)was prepared,in which a hierarchical porous nitrogen-doped carbon with three-dimensional(3D)hollow star-shaped structure is used as a substrate and high-conductivity Ag nanoparticles are coupled with iron nitride(FeNx)nanoparticles.Theoretical calculations indicate that the Mott-Schottky heterojunction as an inherent electric field comes from the two-phase bound of Ag and FeNx,of which electron accumulation in the FeNx phase region and electron depletion in the Ag phase region promote orientated-guiding charge migration.The effective modulation of local electronic struc-tures felicitously reforms the d-band electron-group distribution,and intellectually tunes the mass-transfer reaction energy barriers for both ORR/OER.Additionally,the hollow star-shaped hierarchical por-ous structure provides an apical region for fast mass transfer.Experimental results show that the half-wave potential for ORR is 0.914 V,and the overpotential for OER is only 327 mV at 10 mA cm-2.A rechargeable ZAB with Ag-FeNx-N-C as the air cathode demonstrates long-term cycling performance exceeding 1500 cycles(500 h),with a power density of 180 mW cm-2.Moreover,when employing Ag-FeNx-N-C as the air cathode,flexible ZABs demonstrate a notable open-circuit voltage of 1.42 V and achieve a maximum power density of 65.6 mW cm-2.Ag-FeNx-N-C shows guiding electron/mass transfer route and apical reaction microenvironment for the electrocatalyst architecture in the exploration pro-spects of ZABs.
查看更多>>摘要：The tireless pursuit of supercapacitors with high energy density entails the parallel advancement of well-suited electrode materials and elaborately engineered architectures.Polypyrrole(PPy)emerges as an exceedingly conductive polymer and a prospective pseudocapacitive materials for supercapacitors,yet the inferior cyclic stability and unpredictable polymerization patterns severely impede its real-world applicability.Here,for the first time,an innovative seed-induced in-situ polymerization assisted 3D printing strategy is proposed to fabricate PPy-reduced graphene oxide/poly(vinylidene difluoride-co-hexafluoropropylene)(PVDF-HFP)(PPy-rGO/PH)electrodes with controllable polymerization behavior and exceptional areal mass loading.The preferred active sites uniformly pre-planted on the 3D-printed graphene substrates serve as reliable seeds to induce efficient polypyrrole deposition,achieving an impressive mass loading of 185.6 mg cm-2(particularly 79.2 mg cm-2 for polypyrrole)and a superior areal capacitance of 25.2 F cm-2 at 2 mA cm-2 for a 12-layer electrode.In agreement with theses appeal-ing features,an unprecedented areal energy density of 1.47 mW h cm-2 for a symmetrical device is reg-istered,a rarely achieved value for other PPy/rGO-based supercapacitors.This work highlights a promising route to preparing high energy density energy storage modules for real-world applications.
查看更多>>摘要：Lithium-oxygen(Li-O2)batteries have attracted significant attention due to their ultra-high theoretical energy density.However,serious challenges,such as potential lag,low-rate capability,round-trip effi-ciency,and poor cycle stability,greatly limit their practical application.This review provides a comprehen-sive account of the development of Li-O2 batteries,elucidates the current discharge/charge mechanism,and highlights both the advantages and bottlenecks of this technology.In particular,recent research pro-gress on various cathode materials,such as carbon-based materials,noble metals,and non-noble metals,for Li-O2 batteries is deeply reviewed,emphasizing the impact of design strategies,material structures,chemical compositions,and microphysical parameters on oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)kinetics,as well as discharge products and overall battery performance.This review will also shed light on future research directions for oxygen electrode catalysts and material con-struction to facilitate the development of Li-O2 batteries with maximized electrochemical performance.
查看更多>>摘要：Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustabil-ity in both structure and functionality.The existing reviews on core-shell organic framework photocat-alytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of in-depth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive under-standing and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classi-fication,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in dif-ferent areas,such as H2 evolution,CO2 reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were intro-duced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.
查看更多>>摘要：Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,fur-ther limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different n-phases.Finally,the quasi-2D DJ(EDA)FA9Sn10I31 solar cells achieves a 7.07％power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum bar-rier and carrier transport through the chain length of organic spacer for quasi-2D DJ lead-free perovskites.
查看更多>>摘要：Pristine phase change materials(PCMs)suffer from inherent deficiencies of poor solar absorption and photothermal conversion.Herein,we proposed a strategy of co-incorporation of zero-dimensional(0D)metal nanoparticles and two-dimensional(2D)photothermal materials in PCMs for efficient capture and conversion of solar energy into thermal energy.Highly scattered Co-anchored MoS2 nanoflower clus-ter serving as photon and phonon triggers was prepared by in-situ hydrothermal growth of ZIF67 poly-hedron on 2D MoS2 and subsequent high-temperature carbonization.After encapsulating thermal storage unit(paraffin wax),the obtained composite PCMs integrated high-performance photothermal conversion and thermal energy storage capability.Benefiting from the synergistic enhancement of 0D Co nanoparticles with localized surface plasmon resonance effect,carbon layer with the conjugation effect and 2D MoS2 with strong solar absorption,composite PCMs exhibited a high photothermal conver-sion efficiency of 95.19％.Additionally,the resulting composite PCMs also demonstrated long-term ther-mal storage stability and durable structural stability after 300 thermal cycles.The proposed collaborative co-incorporation strategy provides some innovative references for developing next-generation pho-tothermal PCMs in solar energy utilization.
查看更多>>摘要：Solid polymer electrolytes(SPEs)are urgently required to achieve practical solid-state lithium metal bat-teries(LMBs)and lithium-ion batteries(LIBs).Herein,we proposed a mechanism for modulating interfa-cial conduction and anode interfaces in high-concentration SPEs by LiDFBOP.Optimized electrolyte exhibits superior ionic conductivity and remarkable interface compatibility with salt-rich clusters:(1)polymer-plastic crystal electrolyte(P-PCE,TPU-SN matrix)dissociates ion pairs to facilitate Li+transport in the electrolyte and regulates Li+diffusion in the SEI.The crosslinking structure of the matrix compen-sates for the loss of mechanical strength at high-salt concentrations;(2)dual-anion TFSI-n-DFBOP-m in the Li+solvation sheath facilitates facile Li+desolvation and formation of salt-rich clusters and is con-ducive to the formation of Li conductive segments of TPU-SN matrix;(3)theoretical calculations indicate that the decomposition products of LiDFBOP form SEI with lower binding energy with LiF in the SN sys-tem,thereby enhancing the interfacial electrochemical redox kinetics of SPE and creating a solid interface SEI layer rich in LiF.As a result,the optimized electrolyte exhibits an excellent ionic conductivity of 9.31 × 10-4 S cm-1 at 30 ℃ and a broadened electrochemical stability up to 4.73 V.The designed elec-trolyte effectively prevents the formation of Li dendrites in Li symmetric cells for over 6500 h at 0.1 mA cm-2.The specific Li-Si alloy-solid state half-cell capacity shows 711.6 mAh g-1 after 60 cycles at 0.3 A g-1.Excellent rate performance and cycling stability are achieved for these solid-state batteries with Li-Si alloy anodes and NCM 811 cathodes.NCM 811||Prelithiated silicon-based anode solid-state cell delivers a discharge capacity of 195.55 mAh g-1 and a capacity retention of 97.8％after 120 cycles.NCM 811||Li solid-state cell also delivers capacity retention of 84.2％after 450 cycles.
Elena V.KarasevaElena V.KuzminaBo-Quan LiQiang Zhang...
231-240页
查看更多>>摘要：In lithium-sulfur batteries,cell design,specifically electrolyte design,has a key impact on the battery per-formance.The effect of lithium salt anion donor number(DN)(DN[PF6]-=2.5,DN[N(SO2CF3)2]-=5.4,DN[ClO4]-=8.4,DN[SO3CF3]-=16.9,and DN[NO3]-=21.1)on the patterns of lithium-sulfur batteries and lithium metal electrode performances with sulfolane-based electrolytes is investigated.An increase in DN of lithium salt anions leads to an increase in the depth and rate of electrochemical reduction of sulfur and long-chain lithium polysulfides and to a decrease in those for medium-and short-chain lithium polysul-fides.DN of lithium salt anions has weak effect on the discharge capacity of lithium-sulfur batteries and the Coulomb efficiency during cycling,with the exception of LiSO3CF3 and LiNO3.An increase in DN of lithium salt anions leads to an increase in the cycling duration of lithium metal anodes and to a decrease in the presence of lithium polysulfides.In sulfolane solutions of LiNO3 and LiSO3CF3,lithium polysulfides do not affect the cycling duration of lithium metal anodes.
查看更多>>摘要：Alloy-typed anode materials,endowed innately with high theoretical specific capacity,hold great pro-mise as an alternative to intercalation-typed counterparts for alkali-ion batteries.Despite tremendous efforts devoted to addressing drastic volume change and severe pulverization issues of such anodes,the underlying mechanisms involving dynamic phase evolutions and reaction kinetics have not yet been fully comprehended.Herein,taking antimony(Sb)anode as a representative paradigm,its microscopic operating mechanisms down to the atomic scale during live(de)potassiation cycling are systematically unraveled using in situ transmission electron microscopy.Highly reversible phase transformations at single-particle level,that are Sb (←→)KSb2 (←→)KSb (←→)K5Sb4 (←→)K3Sb,were revealed during cycling.Meanwhile,multiple phase interfaces associated with different reaction kinetics coexisted and this phe-nomenon was properly elucidated in the context of density functional theory calculations.Impressively,previously unexplored unidirectional circulation of reaction interfaces within individual Sb particle is confirmed for both potassiation and depotassiation.Based on the empirical results,the surface diffusion-mediated potassiation-depotassiation pathways at single-particle level are suggested.This work affords new insights into energy storage mechanisms of Sb anode and valuable guidance for tar-geted optimization of alloy-typed anodes(not limited to Sb)toward advanced potassium-ion batteries.
查看更多>>摘要：The development of energy storage devices with high energy density relies heavily on thick film elec-trodes,but it is challenging due to the limited ion transport kinetics inherent in thick electrodes.Here,we report on the preparation of a directional vertical array of micro-porous transport networks on LTO electrodes using a femtosecond laser processing strategy,enabling directional ion rapid transport and achieving good electrochemical performance in thick film electrodes.Various three-dimensional(3D)vertically aligned micro-pore networks are innovatively designed,and the structure,kinetics character-istics,and electrochemical performance of the prepared ion transport channels are analyzed and dis-cussed by multiple characterization and testing methods.Furthermore,the rational mechanisms of electrode performance improvement are studied experimentally and simulated from two aspects of structural mechanics and transmission kinetics.The ion diffusion coefficient,rate performance at 60 C,and electrode interface area of the laser-optimized 60-15％micro-porous transport network electrodes increase by 25.2 times,2.2 times,and 2.15 times,respectively than those of untreated electrodes.Therefore,the preparation of 3D micro-porous transport networks by femtosecond laser on ultra-thick electrodes is a feasible way to develop high-energy batteries.In addition,the unique micro-porous trans-port network structure can be widely extended to design and explore other high-performance energy materials.
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