No abstract

Lithium-sulfur batteries, owing to the multi-electron participation in the redox reaction, possess enormous energy density,w hichh as aroused much attention. Nevertheless, the detrimental shuttlee ffect,v olumee xpansion, and electrical insulation of sulfur,h ave hindered their application. To improvet he cyclability,afunctional host, consisting of Co nanoparticlesa nd N-doped hollow graphitized carbon (Co-NHGC) material, is elaborated, which has the advantages of:1)the graphitized carbon materialw orking as an electronic matrix to improve the utilization rate of sulfur; 2) the hollow structure relieving the stress change caused by volumee xpansion; 3) the rich active sites catalyze the electrochemical reaction of sulfur and entrapp olysulfides. These advantages significantly improvet he performance of the lithium-sulfur batteries. Accordingly,t he S@Co-NHGC cathode exhibits excellent initial specific capacity,h igh coulombic efficiency,a nd excellentr ate performance. Thisw ork utilizes an ovel method of dopaminei ns itue tchingo fa metal-organic framework to synthetize the Co-NHGC host of sulfur,w hich will hopefully provide inspiration for other energy materials.

A Ni–Cu-based high performance hierarchical electrocatalyst for HMFEOR with a low overpotential of 222 mV to achieve the current density of 400 mA cm−2 was synthesized by a facile one-pot hydrothermal process.

The sluggish conversion reaction and accompanied huge volume fluctuation greatly hinder the application of lithium-selenium (Li-Se) batteries. Therefore, reasonably constructing stable carbonaceous host with efficient electrochemical active sites is particularly...