Capturing carbon dioxide in Na–CO₂ batteries: A route for green energy

Limiting the carbon emission to the atmosphere requires the efficient utilization of carbonaceous gases and their capture via well-designed platforms. Metal–CO₂ batteries are currently being demonstrated as the route to utilize CO₂ and produce energy simultaneously. In particular, Na–CO₂ batteries are considered an alternative to Li-batteries because of their abundance and low cost. In the current review, the developments in the field of Na–CO₂ batteries are discussed. Carbon dioxide reactions to the decomposition of discharge products have been discussed elaborately. The main discharge products of Na–CO₂ batteries are Na₂CO₃ and C. In the current review, various strategies are discussed to decompose the discharge products and hence improve cycle stability. The fraction of CO₂ has a substantial influence on cell cycles. A plausible route of battery reaction can be drawn with the help of an ex situ analysis of the electrodes. The final part of the review focuses on the use of solid-state Na-ion conductors in Na–CO₂ batteries.