Porous transition metal-based nanostructures as efficient cathodes for aluminium-air batteries

Abstract

Aluminum-air batteries (AABs) are green and efficient energy systems due to their earth-abundant, safety, low price, excellent theoretical capacity (2.98 Ah/g) and energy density (8.1 Wh/g), which are significant merits in sustainability and practical applications. However, finding an efficient electrocatalyst for oxygen-electrochemistry (i.e., OER/ORR) as an air cathode is one of the barriers to large-scale applications. Porous transition-metal-based (PTM) air cathodes are highly promising for the AABs, owing to their outstanding and tunable physicochemical properties, besides their low-cost, earth-abundance and ease of synthesis. This article emphasizes the recent advances in the fabrication of PTM air cathodes, including monometallic, bimetallic, and multimetallic, to tailor their morphologies for excellent AABs’ performance. Also, a deep discussion on the challenges and current progress is anticipated for practical AABs.