Nickel-catalyzed CNTs enhancing cycle performance of Si@C anodes

The drastic volume change and interfacial instability during repeated cycles are the main obstacles hindering the practical application of silicon anodes. Micro/nano core-shell structures with nickel supports were constructed by spray drying and chemical vapor deposition (CVD) for silicon-carbon anode materials. The catalysis of nickel drives the growth of multidirectionally interconnected CNTs. This three-dimensional electron transport network effectively dissipates mechanical stress and increases the Li⁺ diffusion rate. At the same time, the outer dense carbon coating can inhibit the continuous reduction of electrolyte, which is beneficial to the formation of a thin and uniform SEI. The built micro/nano core-shell structure with a three-dimensional conductive network offers the possibility to alleviate the volume expansion of silicon and stabilize the electrode/electrolyte interface. Therefore, the modified sample maintained a reversible capacity of 1265 mAh g^-1 at 2 A g^-1 after 400 cycles and exhibited an excellent rate capability at 6 A g^-1 (1023 mAh g^-1). This unique micro/nano core-shell structure provides a feasible technical route for constructing highly stable silicon/carbon anodes.