Synthesis of ceria-carbon composite spheres and their application for next-generation lithium rechargeable batteries

Abstract

CeO2 is known to have considerable potential for use as a novel anode material in lithium-ion batteries, but it has inherently low electronic conductivity and low capacity retention due to volumetric or morphological changes during charge-discharge cycling. In this study, we developed an effective synthetic strategy based on the modified Stober method for the first time to obtain CeO2-carbon composite spheres (CeO2-CCS) using PAA (poly(acrylic acid)) and compared it with CeO2 -carbon core shell (CeO2@C) formed without PAA. The CeO2-CCS showed that the CeO2 nanoparticles are well dispersed in the composite spheres with a rough surface, and the surface is coated with an amorphous carbon layer with a thickness of approximately 1-2 nm. This novel architecture provides good access to the electrolyte and accommodates the volume expansion of CeO2 during electrochemical cycling, thereby showing the rate capability and cyclability of CeO2-CCS higher than CeO2@C. We also identified the reaction mechanism of CeO2 using synchrotron-based X-ray absorption spectroscopy. This study provides a comprehensive understanding and strategy for CeO2 as a promising material for anode materials in lithium-ion batteries. (C) 2020 Elsevier B.V. All rights reserved.