C60 as a metal-free catalyst for lithium-oxygen batteries

Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries (LOBs). However, the intrinsic carbon sites are typically inert, necessitating extensive modifications and resulting in a limited density of active sites. Here we present C60 as a metal-free cathode catalyst for LOBs, using density functional theory calculations and experimental verifications. The lithiation reactions on the pristine carbon sites of C60 are energetically favorable due to its curved π-conjugation over the pentagon–hexagon networks. The kinetic analysis specifically reveals low energy barriers for Li2O2 decomposition and Li diffusion on C60. Consequently, C60 exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon nanotubes. Our electrochemical measurements validate the predictions, notably demonstrating that the intrinsic activity of C60 is comparable to that of noble metals.