Molten salt electrosynthesis of Cr₂GeC nanoparticles as anode materials for lithium-ion batteries

The two-dimensional MAX phases with compositional diversity are promising functional materials for electrochemical energy storage. Herein, we report the facile preparation of the Cr₂GeC MAX phase from oxides/C precursors by the molten salt electrolysis method at a moderate temperature of 700°C. The electrosynthesis mechanism has been systematically investigated, and the results show that the synthesis of the Cr₂GeC MAX phase involves electro-separation and in situ alloying processes. The as-prepared Cr₂GeC MAX phase with a typical layered structure shows the uniform morphology of nanoparticles. As a proof of concept, Cr₂GeC nanoparticles are investigated as anode materials for lithium-ion batteries, which deliver a good capacity of 177.4 mAh g^-1 at 0.2 C and excellent cycling performance. The lithium-storage mechanism of the Cr₂GeC MAX phase has been discussed based on density functional theory (DFT) calculations. This study may provide important support and complement to the tailored electrosynthesis of MAX phases toward high-performance energy storage applications.