Self-Reinforced Inductive Effect of Symmetric Bipolar Organic Molecule for High-Performance Rechargeable Batteries

Abstract

Herein, the self-reinforced inductive effect derived from coexistence of both p- and n-type redox-active motifs in a single organic molecule is presented. Molecular orbital energy levels of each motif are dramatically tuned, which leads to the higher oxidation and the lower reduction potentials. The self-reinforced inductive effect of the symmetric bipolar organic molecule, N,N'-dimethylquinacridone (DMQA), is corroborated, by both experimental and theoretical methods. Furthermore, its redox mechanism and reaction pathway in the Li+-battery system are scrutinized. DMQA shows excellent capacity retention at the operating voltage of 3.85 and 2.09 V (vs Li+/Li) when used as the cathode and anode, respectively. Successful operation of DMQA electrodes in a symmetric all-organic battery is also demonstrated. The comprehensive insight into the energy storage capability of the symmetric bipolar organic molecule and its self-reinforced inductive effect is provided. Thus, a new class of organic electrode materials for symmetric all-organic batteries as well as conventional rechargeable batteries can be conceived. The authors scrutinize a self-reinforced inductive effect in a bipolar molecule (N,N'-dimethylquinacridone) through experimental and theoretical methods. This effect originates from the coexistence of p- and n-type motifs, and tunes molecular orbital energy levels, leading to a wider potential gap between its oxidation and reduction. Feasible symmetric all-organic battery based on N,N'-dimethylquinacridone is also demonstrated for the first time.image