The trigonal CrN thin-film electrode for the fast charge-discharge lithium-ion batteries

This work first pioneers the synthesis of trigonal (Formula presented) thin film assisted by the N₂ plasma treatment and systematically investigates its Li + storage properties by using both of the theoretical and experimental approaches. The theoretical calculations reveal that the (001) plane of (Formula presented) thin-film electrode with a large diffusion coefficient of Li+ (∼7.5 × 10−10 m2 s−1) is preferential for the adsorption and diffusion of Li+. The specific capacity of ∼590 mA h g−1 with a Coulombic efficiency higher than 99% could be accomplished by the (Formula presented) thin-film electrode at the current density of 0.1 A g−1 after 100 cycles. Notably, the specific capacity is gradually increased to 600 mA h g−1 at the high current density of 1 A g−1 after 300 cycles. It is demonstrated that the (Formula presented) thin-film electrode possesses the fast charge-discharge capability due to its large diffusion coefficient of Li+. The Li+ storage mechanism of (Formula presented) thin-film electrode is associated with the intercalation of Li+ and conversion. These results show that the N₂ plasma treatment opens up an avenue to fabricate the thin-film nitrides with unusual phases as the anode materials of lithium-ion batteries for the development of all-solid-state thin-film batteries in the future.