The interfacial effect is important for anodes of transition metal dichalcogenides (TMDs) to achieve superior lithium-ion storage performance. In this paper, a MoSsub.2/FeSsub.2 heterojunction is ...synthesized by a simple hydrothermal reaction to construct the interface effect, and the heterostructure introduces an inherent electric field that accelerates the de-embedding process of lithium ions, improves the electron transfer capability, and effectively mitigates volume expansion. XPS analysis confirms evident chemical interaction between MoSsub.2 and FeSsub.2 via an interfacial covalent bond (Mo–S–Fe). This MoSsub.2/FeSsub.2 anode shows a distinct interfacial effect for efficient interatomic electron migration. The electrochemical performance demonstrated that the discharge capacity can reach up to 1217.8 mA h gsup.−1 at 0.1 A gsup.−1 after 200 cycles, with a capacity retention rate of 72.9%. After 2000 cycles, the capacity retention is about 61.6% at 1.0 A gsup.−1, and the discharge capacity can still reach 638.9 mA h gsup.−1. Electrochemical kinetic analysis indicated an enhanced pseudocapacitance contribution and that the MoSsub.2/FeSsub.2 had sufficient adsorption of lithium ions. This paper therefore argues that this interfacial engineering is an effective solution for designing sulfide-based anodes with good electrochemical properties.
Abstract
Invited for this month′s cover is the group of Weitao Zheng at the Jilin University. The image shows the working mechanism of dual‐ion batteries (DIBs). The Review itself is available at
...10.1002/cssc.202201375
.
The global NH.sub.3 production is dominated by Haber-Bosch process, requiring high temperature and pressure. Electrochemical N.sub.2 reduction reaction (NRR) under ambient conditions is a greener ...path for artificial N.sub.2 fixation to NH.sub.3 but calling for efficient catalyst to increase activity and selectivity. Herein, we report the iron-based metal-organic frameworks (MOFs), i.e., MIL-88B-Fe and amine-functionalized MIL-88B-Fe (NH.sub.2-MIL-88B-Fe) as efficient catalysts for electrochemical NRR under ambient temperature and pressure in neutral electrolyte. NH.sub.2-MIL-88B-Fe shows higher NH.sub.3 yield rate of 1.205 x 10.sup.-10 mol s.sup.-1 cm.sup.-2 than MIL-88B-Fe (3.575 x 10.sup.-11 mol s.sup.-1 cm.sup.-2). Furthermore, NH.sub.2-MIL-88B-Fe exhibits the highest Faradaic efficiency of 12.45% at 0.05 V versus RHE. The control experiments prove that NH.sub.3 is produced through electrocatalytic NRR. This work may trigger the interest of using MOFs as highly efficient catalysts for electrochemical NH.sub.3 production.
Rechargeable alkali metal (i.e., lithium, sodium, potassium)‐based batteries are considered as vital energy storage technologies in modern society. However, the traditional liquid electrolytes ...applied in alkali metal‐based batteries mainly consist of thermally unstable salts and highly flammable organic solvents, which trigger numerous accidents related to fire, explosion, and leakage of toxic chemicals. Therefore, exploring non‐flammable electrolytes is of paramount importance for achieving safe batteries. Although replacing traditional liquid electrolytes with all‐solid‐state electrolytes is the ultimate way to solve the above safety issues, developing non‐flammable liquid electrolytes can more directly fulfill the current needs considering the low ionic conductivities and inferior interfacial properties of existing all‐solid‐state electrolytes. Moreover, the electrolyte leakage concern can be further resolved by gelling non‐flammable liquid electrolytes to obtain quasi‐solid electrolytes. Herein, a comprehensive review of the latest progress in emerging non‐flammable liquid electrolytes, including non‐flammable organic liquid electrolytes, aqueous electrolytes, and deep eutectic solvent‐based electrolytes is provided, and systematically introduce their flame‐retardant mechanisms and electrochemical behaviors in alkali metal‐based batteries. Then, the gelation techniques for preparing quasi‐solid electrolytes are also summarized. Finally, the remaining challenges and future perspectives are presented. It is anticipated that this review will promote a safety improvement of alkali metal‐based batteries.
This review provides the latest progress in emerging non‐flammable liquid electrolytes, including non‐flammable organic liquid electrolytes, aqueous electrolytes, and deep eutectic solvent‐based electrolytes, and systematically introduce their flame‐retardant mechanisms and electrochemical behaviors in alkali metal‐based batteries. Furthermore, the gelation techniques for quasi‐solid electrolyte preparation are thoroughly summarized. This review will promote the safety improvement of alkali metal‐based batteries.
With the growing demands for large‐scale energy storage, Zn‐ion batteries (ZIBs) with distinct advantages, including resource abundance, low‐cost, high‐safety, and acceptable energy density, are ...considered as potential substitutes for Li‐ion batteries. Although numerous efforts are devoted to design and develop high performance cathodes and aqueous electrolytes for ZIBs, many challenges, such as hydrogen evolution reaction, water evaporation, and liquid leakage, have greatly hindered the development of aqueous ZIBs. Developing “beyond aqueous” electrolytes can be able to avoid these issues due to the absence of water, which are beneficial for the achieving of highly efficient ZIBs. In this review, the recent development of the “beyond aqueous” electrolytes, including conventional organic electrolytes, ionic liquid, all‐solid‐state, quasi‐solid‐state electrolytes, and deep eutectic electrolytes are presented. The critical issues and the corresponding strategies of the designing of “beyond aqueous” electrolytes for ZIBs are also summarized.
This review focuses on the fundamental understanding of the characteristics and challenges of the “beyond aqueous” electrolytes of zinc‐ion batteries, including conventional organic electrolytes, ionic liquid, all/quasi‐solid‐state electrolytes, and goes deep into the discussion on the pros and cons of each electrolyte. Lastly, this review presents a perspective on the challenges and future opportunities for the “beyond aqueous” electrolytes.
Lithium–air batteries are promising devices for electrochemical energy storage because of their ultrahigh energy density. However, it is still challenging to achieve practical Li–air batteries ...because of their severe capacity fading and poor rate capability. Electrolytes are the prime suspects for cell failure. In this Review, we focus on the opportunities and challenges of electrolytes for rechargeable Li–air batteries. A detailed summary of the reaction mechanisms, internal compositions, instability factors, selection criteria, and design ideas of the considered electrolytes is provided to obtain appropriate strategies to meet the battery requirements. In particular, ionic liquid (IL) electrolytes and solid‐state electrolytes show exciting opportunities to control both the high energy density and safety.
Performance enhancers: Electrolytes for Li–air batteries include non‐aqueous liquid electrolytes, solid‐state electrolytes, aqueous electrolytes, and hybrid electrolytes. This Review shows the importance of electrolytes to the mechanisms and performance of lithium–air batteries and provides a basis for selecting suitable electrolytes. The existing challenges, solutions, as well as guidance for the future direction of this field are also considered.
Electrochromic technologies that exhibit low power consumption have been spotlighted recently. In particular, with the recent increase in demand for paper-like panel displays, faster coloration time ...has been focused on in researching electrochromic devices. Tungsten trioxide (WOsub.3) has been widely used as an electrochromic material that exhibits excellent electrochromic performance with high thermal and mechanical stability. However, in a solid film-type WOsub.3 layer, the coloration time was long due to its limited surface area and long diffusion paths of lithium ions (Li-ions). In this study, we attempted to fabricate a fibrous structure of WOsub.3@poly(ethylene oxide) (PEO) composites through electrospinning. The fibrous and porous layer showed a faster coloration time due to a short Li-ion diffusion path. Additionally, PEO in fibers supports Li-ions being quickly transported into the WOsub.3 particles through their high ionic conductivity. The optimized WOsub.3@PEO fibrous structure showed 61.3 cmsup.2/C of high coloration efficiency, 1.6s fast coloration time, and good cycle stability. Lastly, the electrochromic device was successfully fabricated on fabric using gel electrolytes and a conductive knitted fabric as a substrate and showed a comparable color change through a voltage change from −2.5 V to 1.5 V.
High‐energy lithium‐metal batteries are among the most promising candidates for next‐generation energy storage systems. With a high specific capacity and a low reduction potential, the Li‐metal anode ...has attracted extensive interest for decades. Dendritic Li formation, uncontrolled interfacial reactions, and huge volume effect are major hurdles to the commercial application of Li‐metal anodes. Recent studies have shown that the performance and safety of Li‐metal anodes can be significantly improved via organic electrolyte modification, Li‐metal interface protection, Li‐electrode framework design, separator coating, and so on. Superior to the liquid electrolytes, solid‐state electrolytes are considered able to inhibit problematic Li dendrites and build safe solid Li‐metal batteries. Inspired by the bright prospects of solid Li‐metal batteries, increasing efforts have been devoted to overcoming the obstacles of solid Li‐metal batteries, such as low ionic conductivity of the electrolyte and Li–electrolyte interfacial problems. Here, the approaches to protect Li‐metal anodes from liquid batteries to solid‐state batteries are outlined and analyzed in detail. Perspectives regarding the strategies for developing Li‐metal anodes are discussed to facilitate the practical application of Li‐metal batteries.
Lithium‐metal batteries are promising candidates for high‐energy and cost‐effective energy‐storage systems. Solving the dendritic problem and interfacial instability of the Li‐metal anodes is a prerequisite to their practical utilization. Strategies to protect Li‐metal anodes in liquid and solid‐state electrolytes, which will facilitate the development safe and high‐performance Li‐metal batteries, are reviewed.
Heterostructures have recently been used to generate stable photo-induced currents via photoelectrochemical (PEC) activity. However, the effect of electrolytes on charge-transfer kinetics and the ...generation of photo-induced currents on heterostructures are major challenges in PEC. The effect of the electrolyte on the synthesized photoelectrodes is demonstrated in this study under various conditions using electrochemical impedance spectroscopy, linear sweep voltammetry, chronoamperometry, and Tafel analyses. The lowest transfer kinetics resistance and highest photocurrent densities are achieved in 0.1 M KOH when compared to those in 0.1 M Nasub.2SOsub.4 aqueous electrolytes. Furthermore, various applied voltage effects on the generation of currents have been studied for the synthesized electrodes at a voltage of +0.5 V in both electrolytes. The maximum induced-current achieved was 1.39 mA cmsup.−2 for BW-SO, under illumination in the 0.1 M KOH electrolyte. The BW-SO heterostructure presented enhanced performance due to improved light absorption capability, the lowest resistance values, and the synergistic effect of the heterostructures.
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