The p-n-type PANI/ZnS heterostructure utilizing quantum dot network to achieve low-overpotential photo-assisted lithium–oxygen battery

The lithium-oxygen battery (LOB) is a promising source of green energy due to its energy density. However, the development of this technology is limited by the insoluble discharge product it produces. In this work, a cathode material with a p-n heterostructure of polyaniline (PANI)/ZnS is prepared to trap visible light, utilizing a ZnS quantum dot (ZnS QD) network to form a large number of photogenerated electron–hole pairs, thus promoting the generation and decomposition of Li₂O₂. The prepared PANI/ZnS has an ultra-low overpotential of 0.06 V under illumination. Furthermore, density functional theory theoretical calculation has demonstrated the ability of the heterostructures to adsorb oxygen-containing intermediates, which not only facilitates the growth of Li₂O₂, but also reduces the reaction energy required to decompose Li₂O₂. The present work provides a solution to the problem of insolubility of discharge products in photo-assisted LOB.

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