Coaxial spiral structural polymer/reduced graphene oxide composite as a high-performance anode for potassium ion batteries.

Organic battery materials are ideal anodes for potassium ion batteries (PIBs) due to their structural diversity, abundant resources, and environmental friendliness. Herein, we report a conjugated polymer, polybenzo[1,2-b:4,5-b']dithiophene-4,8-dione (PBDTO), with a coaxial spiral structure. The plane rotation angle of each PBDTO molecule is about 20° apart, which is conducive to the exposure of reactive sites. Introducing reduced graphene oxide (rGO) drastically reduces the material's solubility in the electrolyte and finally obtains PBDTO/rGO with high conductivity, low solubility, and high capacity. As a result, PBDTO/rGO exhibits excellent potassium storage performance with a reversible capacity of 395 mAh g−1 at 100 mA g−1 and long-term cycling stability at high current density, for example, a capacity of 200 mAh g−1 after 1000 cycles at 1 A g−1. This work may inspire researchers to develop efficient organic battery electrodes for next-generation energy storage devices. [Display omitted] • Conjugated polymer with coaxial helical structure was prepared. • The polymer/rGO exhibits low solubility, high conductivity and activity. • The K+ storage capacity could reach 395 mAh g−1 at 100 mA g−1. [ABSTRACT FROM AUTHOR]