Lithium Thiophosphate Functionalized Zirconium MOFs for Li–S Batteries with Enhanced Rate Capabilities

• DOI: 10.1021/jacs.9b09538
• Publication Date: 2019-10-10T20:12:32Z
• Authors: Avery E. Baumann; Xu Han; Megan M. Butala; V. Sara Thoi
• Keywords: Thiophosphate

Zirconium metal–organic frameworks (Zr-MOFs) are renowned for their extraordinary stability and versatile chemical tunability. Several Zr-MOFs demonstrate a tolerance missing linker defects, which create "open sites" that can be used to bind guest molecules on the node cluster. Herein, we strategically utilize these sites stabilize reactive lithium thiophosphate (Li3PS4) within porous framework targeted application in lithium–sulfur (Li–S) batteries. Successful functionalization of Zr-MOF with PS43– is confirmed by an array techniques including NMR, XPS, Raman spectroscopy, X-ray pair distribution function analysis, various elemental analyses. During electrochemical cycling, find even low incorporation extent improves sulfur utilization polysulfide encapsulation deliver sustainably high capacity over prolonged cycling. The functionalized MOF additives also prevent cell damage under abusive cycling conditions recover capacities when returned lower charge/discharge rates, imperative future energy storage devices. Our unique approach marries promising attributes purely inorganic Li3PS4 surface area MOFs, creating Li–S cathode architecture performance beyond sum its component parts. More broadly, this novel strategy opens new avenues facile syntheses "designer materials" where components from discrete disciplines united tailored specific applications.