Naphthalenediimide-carbonylpyridiniums: stable six electron acceptors for organic cathodes

Abstract

Electrochemical energy storage technology has been attracting ever-increasing attention in recent years due to the rapid global clean energy deployment. Novel redox-active organic molecules that can accept multiple electrons are highly sought after as electrode materials to boost the energy density; however, the reported skeletons are highly limited. In this work, we report a class of multi-electron acceptors by conjugation of naphthalenediimide and carbonylpyridinium units through a straightforward approach with high yield. Such skeletons can accept up to six electrons with excellent reversibility and stability. When used as cathode materials for lithium-organic batteries (LOBs), this material delivers a high capacity (227.4 mA h g⁻¹ at 0.2 A g⁻¹), and cycling stability (227 mA h g⁻¹ after 3500 cycles at 1.0 A g⁻¹). This work points to a new direction to diversify bio-derived carbonylpyridinium species that can manipulate multi-electron transfer for high-performance energy storage.