Bimetallic Metal-Organic Framework with High-Adsorption Capacity toward Lithium Polysulfides for Lithium–sulfur Batteries

The practical application of Li-S batteries is largely impeded by the“shuttle effect”generated at the cathode which results in a short life cycle of the battery.To address this issue,this work discloses a bimetallic metal-organic framework(MOF)as a sulfur host material based on Al-MOF,commonly called(Al)MIL-53.To obtain a high-adsorption capacity to lithium polysulfides(Li_(2)S_(x),4≤x≤8),we present an effective strategy to incorporate sulfiphilic metal ion(Cu^(2+))with high-binding energy to Li_(2)S_(x) into the framework.Through a one-step hydrothermal method,Cu^(2+) is homogeneously dispersed in Al-MOF,producing a bimetallic Al/Cu-MOF as advanced cathode material.The macroscopic Li2S4 solution permeation test indicates that the Al/Cu-MOF has better adsorption capacity to lithium polysulfides than monometallic Al-MOF.The sulfur-transfusing process is executed via a melt-diffusion method to obtain the sulfur-containing Al/CuMOF(Al/Cu-MOF-S).The assembled Li-S batteries with Al/Cu-MOF-S yield improved cyclic performance,much better than that of monometallic AlMOF as sulfur host.It is shown that chemical immobilization is an effective method for polysulfide adsorption than physical confinement and the bimetallic Al/Cu-MOF,formed by incorporation of sulfiphilic Cu^(2+) into porous MOF,will provide a novel and powerful approach for efficient sulfur host materials.

Recent advances in metal-organic frameworks for electrochemical performance of batteries

Energy shortage hinders the rapid development of today’s society,and the emergence of electronic travel equipment alleviates this phenomenon to a certain extent.The batteries are the energy storage part of electric equipment.Metal-organic frameworks(MOFs)are a fresh sort of porous crystal materials with controllable structure,large specific surface area,and adjustable pore size.MOFs are good electrode materials,which are used to make a variety of friendly environment,long cycling life and superior energy density of new batteries.Furthermore,MOFs are also used in separators and electrolytes,which have a lot of application space in batteries.In this review,the up-to-date research advance of MOF materials in various kinds of batteries(lithium-ion batteries,lithium oxygen batteries,lithium sulfur batteries,zinc-ion batteries,potassium-ion batteries,etc.)is reviewed.Moreover,concisely introduced several conventional synthesis approaches of MOFs.Finally,Perspectives and directions on the future improvement of MOF in energy storage devices are proposed for meeting the requirement of practical applications.