JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2017
·Vol. 164
·期 12
·A2504
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IF 3.259
Linqi Zeng,Nan Wang,Jun Yang,JiuLin Wang,Yanna NuLi
We report the potential feasibility of a high-capacity and low-cost sulfur cathode that is compatible with nucleophilic electrolytes for Mg/S batteries. The electrochemical performance of sulfur in an easily prepared (PhMgCl)2-AlCl3/THF nucleophilic electrolyte depends on cathode current collectors. A sulfur cathode that uses Cu as a current collector, which is electrochemically stable in the range of operating voltage, exhibits an initial discharge capacity approximately corresponding to 659 mAh g−1, and maintains a reversible capacity of 113 mAh g−1 after 20 cycles at a current density of 10 mA g−1. It is different from the sulfur cathode with few capacities that uses stainless-steel as a current collector. Copper sulfides formed when sulfur is coated on a Cu current collector at 50°C provide a strong chemical interaction between Cu and sulfur, which protects sulfur and increases its compatibility with the electrolyte. A metal-stabilized sulfur cathode provides an effective approach to improve the electrochemical performance of Mg/S batteries in nucleophilic electrolytes.
研究领域:
能源存储
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材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Hao Xu,Dong Zhu,Wen Zhu,Fengzhan Sun,Jianxin Zou,Richard M. Laine,Wenjiang Ding
Rechargeable magnesium sulfur batteries (MSBs) assembled with earth-abundant and safe Mg anodes less prone to form dendrites on surface and sulfur-containing cathodes offer considerable potential for high energy densities. Nevertheless, suitable sulfur host materials and electrolytes are at present key factors that retard commercial introduction. Here, we explore preparation of Ti 3 C 2 @CoO composites as sulfur hosts with high concentration electrolytes consisting of Mg(TFSI) 2 and AlCl 3 in diglyme as new types of MSBs. Density functional theory (DFT) simulations indicate that CoO adsorbs magnesium polysulfides more strongly than Ti 3 C 2 while Ti 3 C 2 is more conductive to Mg 2+ diffusion and transfer than CoO. Coincidentally, use of 1 M electrolyte restrains dissolution of magnesium polysulfides in electrolytes during battery cycling. The experiments indicate that combining Ti 3 C 2 @CoO sulfur hosts and 1 M Mg(TFSI) 2 /AlCl 3 /diglyme electrolyte provides viable MSBs, maintaining discharge capacities of 540 mAh g −1 after 70 cycles at 100 mA g −1 . Mechanistic studies indicate that these MSBs work via a S/MgS x ( x = 2–8) redox process although oxidation of polysulfide to sulfur is not efficient in initial cycling. The systems studied here may offer valuable insights and inspiration in the design of appropriate electrolytes and sulfur-host materials for MSBs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Shuxin Zhang,Yan Huang,Yanna NuLi,Baofeng Wang,Jun Yang,Jiulin Wang
Magnesium–sulfur (Mg–S) batteries have received extensive attention due to the high theoretical energy density, low cost, high safety, and environmental friendliness. In this work, sulfurized pyrolyzed polyacrylonitrile (S@pPAN) composite is used as a cathode material of Mg–S batteries, and a comparative study on the effects of different binders on the electrochemical performance is reported for the first time. The selected binders are commercial organic-soluble poly(vinylidene fluoride) (PVDF) and water-soluble poly(ethylene oxide) (PEO), sodium polyacrylate (PAAS), locust bean gum (LBG), guar gum (GG), carboxymethyl cellulose (SCMC), and β-cyclodextrin (β-CD). The binders significantly affect the physical properties of S@pPAN electrodes and thus the electrochemical performance of the batteries. Compared to the traditional PVDF binder and other water-soluble binders, the S@pPAN electrode with an amorphous PAAS binder has better cycle stability and rate capability. The three-dimensional (3D) network formed from PAAS cross-linking improves the cohesion among the electrode constituents, and the adhesion between the electrode laminate and the current collector maintains the uniformity of electrode surface after cycling. The present work demonstrates the feasibility of using green aqueous binders to enhance the electrochemical performance of Mg–S batteries.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Huimin Xu,Zhonghua Zhang,Jiajia Li,Lixin Qiao,Chenglong Lu,Kun Tang,Shanmu Dong,Jun Ma,Yongjun Liu,Xinhong Zhou,Guanglei Cui
Highly reductive magnesium borohydride [Mg(BH4)2] is compatible with metallic Mg, making it a promising Mg-ion electrolyte for rechargeable Mg batteries. However, pure Mg(BH4)2 in ether-based solutions displays very limited solubility (0.01 M), low oxidative stability (<1.8 V vs Mg), and nucleophilic characteristic, all of which preclude its practical utilization for any battery applications. Herein, we present a multifunctional additive of tris(2H-hexafluoroisopropyl)borate (THFPB) for preparing Mg(BH4)2-based electrolytes. By virtue of the strong electron-acceptor ability of the THFPB molecule, a transparent and high-concentration Mg(BH4)2/THFPB-diglyme (DGM) electrolyte (0.5 M, almost 50 times higher than that of the pristine Mg(BH4)2-DGM electrolyte) is first obtained, which shows dramatic performance improvements, including high ionic conductivity (3.72 mS cm–1 at 25 °C) and high Mg plating/stripping Coulombic efficiency (>99%). The newly-generated active cation and anion species revealed by Raman, NMR and MS spectra, increase the electrochemical potential window from 1.8 V to 2.8 V vs Mg on stainless steel electrode, rendering electrolytes the ability to examine high voltage cathodes. More importantly, on account of the non-nucleophilicity of active electrolyte species, we present the first example of magnesium–sulfur (Mg–S) batteries using Mg(BH4)2-based electrolytes, which exhibit a high discharge capacity of 955.9 and 526.5 mA h g–1 at the initial and 30th charge/discharge cycles, respectively. These achievements not only provide an efficient and specific strategy to eliminate the major roadblocks facing Mg(BH4)2-based electrolytes but also highlight the profound effect of functional additives on the electrochemical performances of unsatisfied Mg-ion electrolytes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energy & Environmental Science
·
2017
·Vol. 10
·期 12
·2616-2625
·
IF 29.518
Aobing Du,Zhonghua Zhang,Hongtao Qu,Zili Cui,Lixin Qiao,Longlong Wang,Jingchao Chai,Tao Lu,Shanmu Dong,Tiantian Dong,Huimin Xu,Xinhong Zhou,Guanglei Cui
Two-electron transfer chemistry based on earth-abundant Mg and S offers great possibilities of delivering higher energy density than current Li-ion technology. The development of non-nucleophilic electrolytes that reversibly and efficiently plate and strip Mg is believed to be a major obstacle to the implementation of this divalent battery technology. In this study, we present a new type of organic magnesium borate-based electrolyte that primarily comprises tetrakis(hexafluoroisopropyl)borate anions [B(HFP)4]− and solvated cations [Mg4Cl6(DME)6]2+, which was synthesized via a facile in situ reaction of tris(hexafluoroisopropyl)borate [B(HFP)3], MgCl2 and Mg powder in 1,2-dimethoxyethane (DME). Rigorous analyses including NMR, mass spectroscopy and single-crystal XRD were conducted to identify the equilibrium species in the abovementioned solution. The as-prepared Mg-ion electrolyte exhibited unprecedented Mg plating/stripping performance, such as high anodic stability up to 3.3 V (vs. Mg/Mg2+), high ionic conductivity of 5.58 mS cm−1, a low overpotential of 0.11 V for plating processes and Coulombic efficiencies greater than 98%. By virtue of the non-nucleophilic nature of this electrolyte, a fully reversible Mg/S battery was constructed that displayed an extremely low overpotential of 0.3 V and a high discharge capacity of up to 1247 mA h g−1 and yielded a specific energy of approximately 1200 W h kg−1 (10 times higher that of the Chevrel benchmark) based on the weight of active sulfur. More significantly, commonly used sulfur-carbon nanotube (S-CNTs) cathodes with S contents of 80 wt% and S loadings of 1.5 mg cm−2 were demonstrated to withstand more than 100 cycles without obvious capacity decay and to enable fast conversion processes, which achieved a charging current rate of up to 500 mA g−1. Our findings convincingly validate the pivotal role of the newly designed non-nucleophilic Mg-ion electrolyte for practical Mg/S battery chemistry.
研究领域:
电化学
·
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Di Wu,Wen Ren,Yang Yang,Jiulin Wang,Yanna NuLi
A magnesium–sulfur (Mg–S) battery system is considered a high-performance candidate for next-generation secondary batteries, because of its prominent advantages such as high safety, low cost, and high energy density. However, the shuttle effect caused by the dissolution of polysulfides leads to irreversible loss of capacity. Herein, we prepare a S0.96Se0.04@CMK3 composite (with a high S + Se content of 82.6 wt %) and employ the composite material as a cathode for Mg batteries with easily prepared hybrid electrolytes. The electronic conductivity of the cathode material increases by 18 orders of magnitude after Se doping, from 5 × 10–28 to 6.5 × 10–10 S m–1. Compared with S@CMK3, doped Se in S0.96Se0.04@CMK3 plays an important role in maintaining capacity stability by lowering polarization, facilitating electron transport, and improving reaction kinetics. The S0.96Se0.04@CMK3 cathode delivers a stable and reversible capacity of 492.9 mAh g–1 after 110 cycles, which is almost twice that of the S@CMK cathode without Se doping, and better rate performance. This Se-doping strategy proposes an effective method to exploit high-performance cathodes for Mg–S batteries.
研究领域:
电化学
·
能源材料
·
无机化学
·
纳米材料
·
二次电池
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）