INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
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IF 4.2
Jiafeng Qian,Shiju Cai,Jianxiong Hu,Chenyi Wang,Guang Li
In order to promote the conduction and stability of anion exchange membranes (AEMs) for the vanadium redox flow battery (VRFB), a kind of quaternary ammonium AEMs with flexible side chains (PAES-4N-xx, xx represents the proportion of monomers containing an amino structure) are prepared via aromatic nucleophilic polycondensation and grafting reactions. The ion exchange capacity (IEC) values of PAES-4N-xx are in the range of 1.58–2.10 mmol g–1, and their water uptake, swelling ratio, SO42– conductivity, and VO2+ permeability at 30 °C are in the range of 15–52%, 5–17%, 13.5–22.4 mS cm–1, and 8.6–43.3 cm2 min–1, respectively. In addition, PAES-4N-xx display good stability, and their retention ratio of IEC and conductivity reach more than 95% after soaking in a solution of 1.5 mol L–1 VO2+/3 mol L–1 H2SO4 at RT for 30 days. The typical battery assembled with PAES-4N-40 shows high efficiency; its Coulomb efficiency (CE), voltage efficiency (VE), and energy efficiency (EE) are in the range of 93.5%–97.8%, 88.6%–70.5%, and 69.0%–84.9% at the fixed current density which is between 40 mA cm–2 and 200 mA cm–2, respectively. The battery also has good stability for 100 cycles of charging and discharging at a current density of 40 mA cm–2, and its retention of EE reaches 96.5%. The introduction of flexible side chains and dense cationic structures can effectively improve the performance of the VRFB.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
ACS Nano
·
2019
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IF 13.903
Jiaman Liu,Liwei Yu,Xingke Cai,Usman Khan,Zhengyang Cai,Jingyu Xi,Bilu Liu,Feiyu Kang
Two-dimensional (2D) hexagonal boron nitride (h-BN) has attracted great interest due to its excellent chemical and thermal stability, electrical insulating property, high proton conductivity, and good flexibility. Integration of 2D h-BN into commercial proton exchange membranes (PEMs) has the potential to improve ion selectivity while maintaining the proton conductivity of PEMs simultaneously, which has been a longstanding challenge in membrane separation technology. Until now, such attempts are only limited in mechanically exfoliated small area h-BN and in proof-of-concept devices, due to the difficulty of growing and transferring large area uniform h-BN monolayers. Here, we develop a space-confined chemical vapor deposition approach and achieve the growth of wafer-scale uniform h-BN monolayer films on Cu rolls. We further develop a Nafion functional layer assisted transfer method which effectively transfers as-grown h-BN monolayer films from the Cu roll to sulfonated poly(ether ether ketone) (SPEEK) membrane. The as-fabricated Nafion/h-BN/SPEEK sandwich structure is used as the membrane and compared with the pure SPEEK membrane for flow batteries. Results show that the sandwich membrane exhibits ion selectivity 3-fold greater than that of a pure SPEEK membrane (i.e., 32.1 × 104vs 9.7 × 104 S min cm–3). In addition, we fabricate vanadium flow batteries using the Nafion/h-BN/SPEEK sandwich membrane and find that the sandwich structure does not affect the proton transport but inhibits vanadium crossover at low current density (<120 mA cm–2) due to the selective blocking of vanadium ions by 2D h-BN. As a result, the sandwich membrane exhibits a significantly improved Coulombic efficiency and energy efficiency, ∼95% and ∼91%, respectively. Our results suggest that a functional layer/2D film/target substrate-based sandwich structure shows clear potential for future 2D material-based membranes in separation technologies.
研究领域:
材料科学
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能源技术
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DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2020
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IF 4.473
Yang Dong,Ming Jia,Yuanyuan Wang,Jianzhong Xu,Yongchang Liu,Lifang Jiao,Ning Zhang
Rechargeable aqueous zinc/vanadium pentoxide (Zn/V2O5) battery chemistry has recently attracted a great attention due to its high safety, material abundance, cost effectiveness, and desirable energy density. However, the reaction mechanism of V2O5 in an aqueous electrolyte remains a topic of discussion, and the limited life span resulting from the active materials dissolution hinders the further development of the Zn/V2O5 battery. Here, we report a long-life aqueous Zn/V2O5 battery using a simply ball-milled V2O5 cathode, a concentrated aqueous ZnSO4 electrolyte, and a metallic Zn anode. Electrochemical, structural, and spectroscopic analyses reveal that the V2O5 electrode experiences a highly reversible proton (H+) and Zn2+ co-intercalation mechanism in aqueous media, which differs from the conventional cognition that Zn2+ ion as the only charge carrier inserts into the V2O5 host. The electrolyte-involved (dis)appearance of zinc sulfate hydroxide on the electrodes’ surface caused by H+ (de)intercalation has also been clarified. In addition, the optimized 3 M ZnSO4 electrolyte can not only suppress the dissolution of the V2O5 cathode but also enhance the stability of the Zn anode, thereby enabling the stable operation of the Zn/V2O5 battery with a reversible capacity of 357 mAh g–1 after 2000 cycles without obvious decay at 2.0 A g–1. This work opens up frontiers in the mechanism insight and electrolyte formulation for aqueous Zn batteries.
研究领域:
材料科学
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电化学
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DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-10
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IF 15.7
Zhang Xiaotan,Li Jiongxian,Wang Tianqi,Gong Yuxiang,Zhou Jiang
Conventional lattice orientation modulation of metal negative electrodes typically aims to expose low-surface-energy crystal planes, which, due to their high thermodynamic stability and low migration barrier, promote planar electrodeposition behavior. However, we demonstrate that a single [11 \(\bar{2}\) 0]-oriented Zn metal negative electrode with higher surface energy can also achieve uniform Zn deposition. Advanced atomic-level transmission electron microscopy reveals the crystallographic orientation of Zn deposits along the growth direction, showing zero lattice mismatch at the epitaxial interface. The [11 \(\bar{2}\) 0]-oriented Zn electrode shows high reversibility over 4000 cycles in Zn| |Cu cells at 40.0 mA/cm 2 and 4.0 mAh/cm 2 and enhanced cycling stability over 2600 cycles with 94.7% capacity retention in Zn| |NH 4 V 4 O 10 cells at 2.0 A/g. This concept is further expanded to other Zn metal negative electrodes with any single lattice orientation, with growth rates and grain boundary (GB) characteristics elucidated through simulated calculations and crystallographic characterizations. Grains within a single-oriented metal negative electrode exhibit uniform growth rates, superior GB stability, and an ordered atomic arrangement, promoting spontaneous dislocation-free homoepitaxy. Our study deepens the understanding of lattice modulation and provides valuable insights for engineering other high-reversibility metal negative electrodes.
研究领域:
材料科学
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电化学
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纳米技术
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晶体学
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储能技术
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电池技术
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）