Thiophene-based conjugated networks tailored with phenylacetylene motifs for advanced lithium-ion batteries

Abstract

Conjugated microporous polymers (CMPs) have attracted increasing interest for their use as electrode materials for lithium-ion batteries (LIBs) due to their microporous structures and robust conjugated networks. In this work, two novel CMPs containing thiophene and phenylacetylene were synthesized for their use as anode materials for LIBs. Doped thiophene and phenylacetylene greatly enhance interactions between electron-rich organic frameworks and Li+, endowing both TTB-TEB and TTB-DEB outstanding electrochemical performance. Notably, TTB-TEB outperforms TTB-DEB, primarily originating from its higher specific surface area, greater π-conjugated stability, and more highly crosslinked porous architecture. Specifically, TTB-TEB has a capacity as high as 620 mA h g-1 at 2000 mA g-1 after 1000 cycles, and an ultrahigh capacity retention of 454 mA h g-1 at 5000 mA g-1 after 1000 cycles. The research results are great improvements for CMPs-base anodes, meanwhile this work provides valuable experience in the rational design of CMPs for next-generation energy storage devices.