3D ordered macroporous MoO2 attached on carbonized cloth for high performance free-standing binder-free lithium–sulfur electrodes

Abstract

Lithium–sulfur (Li–S) batteries have received increasing attention due to their high energy density. However, it is still challenging to inhibit the diffusion of polysulfides and achieve high sulfur utilization. Herein, we designed and prepared a free-standing and binder-free electrode for high-performance Li–S batteries by in situ growth of three-dimensional ordered macroporous MoO₂ on carbonized nonwoven cloth (3DOM MoO₂/CC). After the uptake of Li₂S₆, the obtained MoO₂/CC–Li₂S₆ electrode with a high sulfur loading of 3.26 mg cm⁻² delivers a large discharge capacity of 1267 mA h g⁻¹ at 0.1C. A high discharge capacity of 621 mA h g⁻¹ is still retained after 500 cycles at 2C. The excellent electrochemical performance of this MoO₂/CC–Li₂S₆ electrode is attributed to the unique nanostructure and strong chemical interaction between MoO₂ and polysulfides. 3DOM MoO₂ not only guarantees the high loading of sulfur but also suppresses the diffusion of polysulfides. The carbonized nonwoven cloth (CC) functions as the basic support for 3DOM MoO₂, enhancing the electronic conductivity and mechanical properties of the free-standing electrodes. This work provides a feasible strategy for the construction of high-performance free-standing binder-free Li–S electrodes.