Scalable synthesis of a dual-confined SiO/one-dimensional carbon/amorphous carbon anode based on heterogeneous carbon structure evolution

Abstract

The modification of dual carbon-confined structures formed by one-dimensional carbon (1D-C) and amorphous carbon (a-C) exhibits great potential for improving the cycling stability of SiO anodes. To prepare the ideal dual confined structure through a continuous in situ deposition process, we have revealed the evolution law of the heterogeneous carbon structure from 1D-C to a-C through systematic kinetic experiments based on the gradual transformation of catalyst activity in the deposition process. Inspired by this law, a unique one-step deposition process was proposed to prepare the dual confined SiO/1D-C/a-C composites. The conductive network constructed by 1D-C and the stable dynamic interface composed of onion-like a-C completely encapsulated the SiO particles, which ensured the superior electrical contact of the particles during cycling and effectively avoided the electrode pulverization. Therefore, the resultant SiO/1D-C/a-C composite showed excellent cycling stability with a specific reversible capacity of 1006 mA h g⁻¹, even after 250 cycles (capacity retention of 82.1%). Furthermore, the continuous one-step deposition process brought great possibilities for the large-scale production of SiO/1D-C/a-C.