Candle soot-metal-organic framework-based hierarchical electrode as high-performance anode for Li-ion batteries

Recently, cobalt oxide-based materials have been considered high-performance anode materials. However, cobalt oxide materials display drawbacks such as capacity fade, poor cycle life, and substantial structural strain. In this work, we report a facile synthesis of carbon-cobalt oxide composite to improve the electrode's storage capabilities and cycle life. First, metal–organic framework-based cobalt oxide nano leaves are synthesized by simple coprecipitation followed by calcination. After that, candle soot-derived carbon nanoparticles are uniformly deposited on the cobalt oxide nano leaves by a simple flame synthesis method to form a composite electrode. The fractal-like interconnected carbon nanoparticles improve the electron conducting pathways. In contrast, metal–organic framework-derived porous cobalt oxide nano leaves enhance energy storage abilities through reversible conversion reactions. The superior performance of the composite electrode is established from the galvanostatic charge–discharge experiments. Also, the composite electrode has delivered outstanding specific capacities of 811 and 503 mAh g⁻¹ at 50 and 1000 mA g⁻¹ current densities, respectively. Furthermore, the composite electrode exhibited good cyclic stability at 1000 mA g⁻¹ current density by delivering an excellent specific charge capacity of 490 mAh g⁻¹ even after 400 cycles. Therefore, these superior electrochemical properties confirm the potential applicability in high-performance and stable Li-ion batteries.