Jump to main content
Jump to site search


A conductive selenized polyacrylonitrile cathode in nucleophilic Mg2+/Li+ hybrid electrolytes for magnesium-selenium batteries

Abstract

Rechargeable magnesium-selenium (Mg-Se) batteries are promising electrochemical systems with high energy density than traditional magnesium batteries. It has been widely accepted that electrophilic selenium cathode can only chemically compatible with non-nucleophilic electrolytes. Herein, we firstly report Mg-Se batteries containing selenized polyacrylonitrile (Se/PAN) cathode, Mg anode and nucleophilic electrolyte. The Se/PAN composite with a moderate Se content (45.37 wt%) exhibits significantly high rate capacity and cycling stability in easily prepared (PhMgCl)2-AlCl3 based electrolyte. It delivers an initial discharge capacity of 338.2 mAh g-1 based on the mass of the whole composite at a rate of 100 mA g-1, and the capacity can maintain at around 188.4 mAh g-1 after 100 cycles. Even at a high rate of 400 mA g-1, a capacity of 118.3 mAh g-1 can be obtained after 800 cycles with an inappreciable capacity decay of 0.021% per cycle, which is comparable to that of previously reported Mg-Se batteries using non-nucleophilic electrolytes. The excellent performance is attributed not only to the structure advantage of the material, but to the compatible electrolyte. Well trapped Sen chains in the polymer backbone facilitate electron/ion transport and improve reaction kinetics, leading to high reactivity and utilization of Se with suppressed shuttle effect. In addition, the polymer backbone could buffer the volume changes during the electrochemical process and mitigate the structural degradation. Furthermore, the effective SEI film preserves the cathode and prevents it from irreversible reaction with electrolyte. This work proposes a combination of conductive Se/PAN cathode and compatible electrolyte for promoting the performance of Mg-Se batteries, sparking intense research interest in Mg-Se batteries with easily prepared nucleophilic electrolytes.

Back to tab navigation

Supplementary files

Publication details

The article was received on 22 May 2018, accepted on 03 Aug 2018 and first published on 03 Aug 2018


Article type: Paper
DOI: 10.1039/C8TA04772C
Citation: J. Mater. Chem. A, 2018, Accepted Manuscript
  •   Request permissions

    A conductive selenized polyacrylonitrile cathode in nucleophilic Mg2+/Li+ hybrid electrolytes for magnesium-selenium batteries

    H. Yuan, Y. Yang, Y. NuLi, J. Yang and J. Wang, J. Mater. Chem. A, 2018, Accepted Manuscript , DOI: 10.1039/C8TA04772C

Search articles by author

Spotlight

Advertisements