Insoluble Naphthoquinone‐Derived Molecular Cathode for High‐Performance Lithium Organic Battery
Abstract
Abstract Organic electrode materials have attracted significant attention for rechargeable lithium organic batteries owing to the anticipated electrochemical property and environmentally friendly features. Benzoquinone and naphthoquinone as the simplest quinone substances have been considered as promising cathode materials because of their high theoretical specific capacities and discharge voltages. However, they are soluble in most organic liquid electrolytes, which results in poor electrochemical performance. Herein, a novel molecular cathode material based on naphthoquinone, i.e., 2,2'‐(1,4‐phenylenedithio) bis(1,4‐naphthoquinone) (1,4‐PNQ), is designed and synthesized. It shows greatly decreased solubility as a result of strong intermolecular interactions. In a lithium half cell, it exhibits high carbonyl utilization of close to 100% with a high initial capacity of 231 mAh g ‐1 . Meanwhile, 1,4‐PNQ presents improved cyclability, retaining a high capacity of 185 mAh g ‐1 after 120 cycles. Remarkably, it retains 93.5% of the initial capacity after 500 cycles at 5 C rate. This work provides a novel molecular design strategy to develop naphthoquinone‐derived cathode materials for high performance lithium organic batteries.