Covalently Anchoring and In Situ Electrochemical Activation of Conductive Selenophene-Organic Matrix-Driven High-Efficiency Potassium Organic Batteries

Abstract

Organic electrode materials (OEMs) constitute an attractive class of energy storage materials for potassium-ion batteries, but their application is severely hindered by sluggish kinetics and limited capacities. Herein, inorganic molecules covalent combination strategy is proposed to drive advanced potassium organic batteries. Specifically, molecular selenium, possessing high potential of conductivity and electroactivity, is covalently bonded with organic matrix, that is symmetrical selenophene-annulated dipolyperylene diimide (PDI2-2Se), is designed to verify the feasibility. The inorganic-anchored OEM (PDI2-2Se) can be electrochemically activated to form organic (PDI2 matrix)–inorganic (Se) hybrids during initial cycles. State-of-the-art 3D tomography reveals that a “mutual-accelerating” effect was realized, that is, the 10-nm Se quantum dots, possessing high conductivity, facilitate charge transfer in organics as well store K⁺-ions, and organic PDI2 matrix benefits the encapsulation of Se, thereby suppressing shuttle effect and volume fluctuation during cycling, endowing resulting PDI2/Se hybrids with both high-rate capacities and longevity. The concept of inorganic-configurated OEM through covalent bonds, in principle, can also be extended to design novel functional organic-redox electrodes for other high-performance secondary batteries.