Mechanochemical optimization of ZIF-8/Carbon/S-8 composites for lithium-sulfur batteries positive electrodes

Author(s)

Souza, Breno L. ^[1] ; Chauque, Susana ^[1] ; de Oliveira, Paulo F. M. ^[1] ; Emmerling, Franziska F. ^[2] ; Torresi, Roberto M. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[2] BAM Fed Inst Mat Res & Testing, Richard Willstatter Str 11, D-12489 Berlin - Germany

• Document type: Journal article
• Source: JOURNAL OF ELECTROANALYTICAL CHEMISTRY; v. 896, n. SI SEP 1 2021.
• Web of Science Citations: 0

Abstract

The application of lithium-sulfur (Li-S) batteries is still limited by their rapid capacity fading. The pulverization of the sulfur positive electrode after the lithiation and the consequence dissolution of long chain polysulfides in organic solvents lead to the shuttle effect. To address these issues, here we report the mechanochemical preparation of ZIF-8 (Zeolitic Imidazole Framework-8)-based composites as sulfur hosts for positive electrodes in Li-S batteries. We studied different methods for the incorporation of conductive carbon. Also, the replacement of Zn2+ metal centers by other bivalent metals (Cu2+, Co2+ and Ni2+), enabled the preparation of other ZIF8-based materials. The positive electrode ZIF-8/C/S8 showed initial discharges of 772 mA h g-1 while the pristine one, ZIF-8/S8, displayed 502 mA h g-1. The enhanced performance of 54% for ZIF-8/C/S8 indicates that the direct mechanochemical synthesis of ZIF-8 with conductive carbon is beneficial at initials charge/discharge process in comparison to traditional slurry preparation (ZIF-8/S8). Also, the Li2S6 absorption tests shows 87% of discoloration with ZIF-8/C/S8, confirming the better polysulfides absorption. (AU)

• FAPESP's process: 17/15456-0 - Solid-state mechanochemistry as a greener route for synthesis of advanced materials
• Grantee: Paulo Filho Marques de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/11320-0 - High performance electrochemical capacitors
• Grantee: Susana Chauque
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/26308-7 - Optimization of the physicochemical properties of nano -structured materials for applications in molecular recognition, catalysis and energy conversion/storage
• Grantee: Roberto Manuel Torresi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/09341-1 - Lithium-sulfur batteries: development of new generation of positive electrodes based on composites of MOFs/sulfur
• Grantee: Breno Luiz de Souza
• Support Opportunities: Scholarships in Brazil - Doctorate