An Organic–Inorganic Hybrid Cathode Based on S–Se Dynamic Covalent Bonds

Abstract

A diphenyl trisulfide–selenium nanowire (DPTS‐Se) organic–inorganic hybrid cathode material is presented for rechargeable lithium batteries. During discharge, three voltage plateaus associated with three lithiation processes are observed. During recharge, the combination of the radicals formed upon delithiation leads to several new phenyl sulfoselenide compounds which are confirmed by HPLC‐QTof‐MS. The hybrid cathode exhibits superior cycling stability over pristine Se or DPTS as cathode alone. The first discharge shows a capacity of 96.5 % of the theoretical specific capacity and the cell retains 69.2 % of the initial capacity over 250 cycles. The hybrid cathode also shows a high Coulombic efficiency of over 99 % after 250 cycles. This study demonstrates that the combination of organic polysulfide and selenium can not only improve the utilization of active materials but also enhance the cycling performance.

Electrochemistry of Electrode Materials Containing S−Se Bonds for Rechargeable Batteries

“…Recently, our group reported a diphenyl trisulfide (Ph‐S 3 ‐Ph)‐Se nanowire (DPTS‐Se) hybrid cathode based on S−Se dynamic covalent bonds for Li batteries . This is the first time an organic polysulfide was combined with an inorganic Se electrode.…”

“…Reprinted with permission from refs. and . Copyright 2020, Wiley‐VCH, Weinheim, and copyright 2019, Nature Publishing Group, respectively.…”

Highly Efficient Organosulfur and Lithium‐Metal Hosts Enabled by C@Fe3N Sponge

“…[15] More recently, polymers containing multiple SÀ S bonds that have been synthesized through inverse vulcanization, [16] incorporation of covalent frameworks, [17] and condensation reactions have been demonstrated. [18] In addition to polymers, linear compounds, cyclics, [6c] hybrids, [19] and compounds with unique functional groups have been employed as cathode materials. [20] Previous reports have demonstrated that the organosulfur compounds can decently mitigate the shuttle effect in Li-S batteries.…”