查看更多>>摘要：Hydrogen is known for its elevated energy density and environmental compatibility and is a promising alternative to fossil fuels.Alkaline water electrolysis utilizing renewable energy sources has emerged as a means to obtain high-purity hydrogen.Nevertheless,electrocatalysts used in the process are fabri-cated using conventional wet chemical synthesis methods,such as sol-gel,hydrothermal,or surfactant-assisted approaches,which often necessitate intricate pretreatment procedures and are vulnerable to post-treatment contamination.Therefore,this study introduces a streamlined and environmentally con-scious one-step potential-cycling approach to generate a highly efficient trimetallic nickel-iron-copper electrocatalyst in situ on nickel foam.The synthesized material exhibited remarkable performance,requiring a mere 476 mV to drive electrochemical water splitting at 100 mA cm-2 current density in alka-line solution.Furthermore,this material was integrated into an anion exchange membrane water-splitting device and achieved an exceptionally high current density of 1 A cm-2 at a low cell voltage of 2.13 V,outperforming the noble-metal benchmark(2.51 V).Additionally,ex situ characterizations were employed to detect transformations in the active sites during the catalytic process,revealing the struc-tural transformations and providing inspiration for further design of electrocatalysts.
查看更多>>摘要：With the depletion of fossil fuels and the demand for high-performance energy storage devices,solid-state lithium metal batteries have received widespread attention due to their high energy density and safety advantages.Among them,the earliest developed organic solid-state polymer electrolyte has a promising future due to its advantages such as good mechanical flexibility,but its poor ion transport per-formance dramatically limits its performance improvement.Therefore,single-ion conducting polymer electrolytes(SICPEs)with high lithium-ion transport number,capable of improving the concentration polarization and inhibiting the growth of lithium dendrites,have been proposed,which provide a new direction for the further development of high-performance organic polymer electrolytes.In view of this,lithium ions transport mechanisms and design principles in SICPEs are summarized and discussed in this paper.The modification principles currently used can be categorized into the following three types:enhancement of lithium salt anion-polymer interactions,weakening of lithium salt anion-cation interac-tions,and modulation of lithium ion-polymer interactions.In addition,the advances in single-ion con-ductors of conventional and novel polymer electrolytes are summarized,and several typical high-performance single-ion conductors are enumerated and analyzed in what way they improve ionic con-ductivity,lithium ions mobility,and the ability to inhibit lithium dendrites.Finally,the advantages and design methodology of SICPEs are summarized again and the future directions are outlined.
查看更多>>摘要：The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Pt-based noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O* to OH* and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and PtPd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified PtPd aerogel exhibited the higher half-wave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.
查看更多>>摘要：The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service con-ditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84％capacity retention at-20 ℃)and intrinsic self-healing capabilities(95％capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc‖manganese dioxide cell an economically feasible battery for the state-of-the-art applica-tions.The Zn‖AF/SH-Hydrogel‖MnO2 device offers a near-theoretical specific capacity of 285 mA h g-1 at 0.1 Ag-1(Coulombic efficiency ≈100％),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel elec-trolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices.
查看更多>>摘要：Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promis-ing electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical performance.Severe volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engi-neering are crucial to circumvent these disadvantages.Herein,this review provides an in-depth discus-sion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various MBs.In the following,recent design and engi-neering strategies of metal tellurides,including morphology engineering,compositing,defect engineer-ing and heterostructure construction,for high-performance MBs are summarized.The primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and cor-responding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical performance.In closing,outlooks and prospects for future development of metal tellurides are proposed.This work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.
查看更多>>摘要：Vanadium-based electrodes are regarded as attractive cathode materials in aqueous zinc ion batteries(ZIBs)caused by their high capacity and unique layered structure.However,it is extremely challenging to acquire high electrochemical performance owing to the limited electronic conductivity,sluggish ion kinetics,and severe volume expansion during the insertion/extraction process of Zn2+.Herein,a series of V2O3 nanospheres embedded N-doped carbon nanofiber structures with various V2O3 spherical mor-phologies(solid,core-shell,hollow)have been designed for the first time by an electrospinning tech-nique followed thermal treatments.The N-doped carbon nanofibers not only improve the electrical conductivity and the structural stability,but also provides encapsulating shells to prevent the vanadium dissolution and aggregation of V2O3 particles.Furthermore,the varied morphological structures of V2O3 with abundant oxygen vacancies can alleviate the volume change and increase the Zn2+ pathway.Besides,the phase transition between V2O3 and ZnXV2O5-m·nH2O in the cycling was also certified.As a result,the as-obtained composite delivers excellent long-term cycle stability and enhanced rate performance for coin cells,which is also confirmed through density functional theory(DFT)calculations.Even assembled into flexible ZIBs,the sample still exhibits superior electrochemical performance,which may afford new design concept for flexible cathode materials of ZIBs.
查看更多>>摘要：Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance hetero-junctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also challenging.Besides,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold climates.Herein,cross-linking nanoarchitectonics of WS2/Ti3C2Tx heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of hetero-junction design and BIEF for modifying the reaction kinetics and electrochemical activity.Particularly,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti3C2Tx to layered WS2,spontaneously forming the BIEF and"ion reservoir"at the heterogeneous interface.Besides,the generation of cross-linking pathways further promotes the trans-portation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure coupling.Consequently,superior sodium storage performance is obtained for the WS2/Ti3C2Tx heterojunction,with only 0.2％decay per cycle at 5.0 A g 1(25 ℃)up to 1000 cycles and a high capacity of 293.5 mA h g-1(0.1 A g-1 after 100 cycles)even at-20 ℃.Importantly,the spontaneously formed BIEF,accompanied by"ion reservoir",in heterojunction provides deep understandings of the correlation between structure fabri-cated and performance obtained.
Rose Anne AcederaAlicia Theresse DumlaoDJ Donn MatienzoMaricor Divinagracia...
646-669页
查看更多>>摘要：Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based catalysts.TMPs have been produced in various morphologies,including hollow and porous nanostructures,which are features deemed desirable for electrocatalytic materials.Templated synthesis routes are often responsible for such morphologies.This paper reviews the latest advances and existing challenges in the synthesis of TMP-based OER and HER catalysts through templated methods.A compre-hensive review of the structure-property-performance of TMP-based HER and OER catalysts prepared using different templates is presented.The discussion proceeds according to application,first by HER and further divided among the types of templates used-from hard templates,sacrificial templates,and soft templates to the emerging dynamic hydrogen bubble template.OER catalysts are then reviewed and grouped according to their morphology.Finally,prospective research directions for the synthesis of hollow and porous TMP-based catalysts,such as improvements on both activity and stability of TMPs,design of environmentally benign templates and processes,and analysis of the reaction mechanism through advanced material characterization techniques and theoretical calculations,are suggested.
查看更多>>摘要：The development of aqueous battery with dual mechanisms is now arousing more and more interest.The dual mechanisms of Zn2+(de)intercalation and I-/I2 redox bring unexpected effects.Herein,differing from previous studies using ZnI2 additive,this work designs an aqueous BiI3-Zn battery with self-supplied I-.Ex situ tests reveal the conversion of BiI3 into Bi(discharge)and BiOI(charge)at the 1st cycle and the dissolved I-in electrolyte.The active I-species enhances the specific capacity and discharge medium voltage of electrode as well as improves the generation of Zn dendrite and by-product.Furthermore,the porous hard carbon is introduced to enhance the electronic/ionic conductivity and adsorb iodine species,proven by experimental and theoretical studies.Accordingly,the well-designed BiI3-Zn battery delivers a high reversible capacity of 182 mA hg-1 at 0.2 A g-1,an excellent rate capability with 88 mA h g-1 at 10 A g-1,and an impressive cyclability with 63％capacity retention over 20 K cycles at 10 A g-1.An excellent electrochemical performance is obtained even at a high mass loading of 6 mg cm2.Moreover,a flexible quasi-solid-state BiI3-Zn battery exhibits satisfactory battery perfor-mances.This work provides a new idea for designing high-performance aqueous battery with dual mechanisms.
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