Boosting a practical Li-CO<sub>2</sub> battery through dimerization reaction based on solid redox mediator.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38280844.
- Also identified by DOI 10.1038/s41467-024-45087-4 and PMC identifier 11258291.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Li-CO<sub>2</sub> batteries offer a promising avenue for converting greenhouse gases into electricity. However, the inherent challenge of direct electrocatalytic reduction of inert CO<sub>2</sub> often results in the formation of Li<sub>2</sub>CO<sub>3</sub>, causing a dip in output voltage and energy efficiency. Our innovative approach involves solid redox mediators, affixed to the cathode via a Cu(II) coordination compound of benzene-1,3,5-tricarboxylic acid. This technique effectively circumvents the shuttle effect and sluggish kinetics associated with soluble redox mediators. Results show that the electrochemically reduced Cu(I) solid redox mediator efficiently captures CO<sub>2</sub>, facilitating Li<sub>2</sub>C<sub>2</sub>O<sub>4</sub> formation through a dimerization reaction involving a dimeric oxalate intermediate. The Li-CO<sub>2</sub> battery employing the Cu(II) solid redox mediator boasts a higher discharge voltage of 2.8 V, a lower charge potential of 3.7 V, and superior cycling performance over 400 cycles. Simultaneously, the successful development of a Li-CO<sub>2</sub> pouch battery propels metal-CO<sub>2</sub> batteries closer to practical application.