Arylamine-Linked Porous Organic Polymers with Abundant Redox-Active Sites as High-Capacity and High-Rate Organic Cathodes for Lithium-Ion Batteries.

Abstract

Redox-active porous organic polymers (POPs) have emerged as promising and sustainable organic cathode materials (OCMs) for lithium-ion batteries (LIBs). However, their performance is significantly limited by insufficient redox-active sites and low intrinsic conductivity. Herein, a series of novel arylamine-linked and bipolar POPs (denoted as HATN-AQ, HATN-BQ, HATN-CBD, and HATN-PTO) are designed and prepared as OCMs for LIBs. Benefiting from their high density of redox-active sites, bipolar feature, and arylamine linkage, these POPs exhibited high capacity, high rate, and excellent long-term cycling stability. Among them, HATN-PTO displayed an ultrahigh reversible capacity of 329.6 mAh g^-1 at 0.2 A g^-1 with a high energy density of 716.7 Wh kg^-1, outstanding rate performance (208.7 mAh g^-1 at 20 A g^-1), and superior cycling stability (188.9 mAh g^-1 capacity retained after 500 cycles at 1 A g^-1). Furthermore, the HATN-PTO//graphite full battery exhibited a high specific capacity of 227.3 mAh g^-1 at 0.2 A g^-1 and maintained a high capacity of 99.1 mAh g^-1 after 200 cycles at 0.5 A g^-1. Ex situ FT-IR and XPS spectra combined with theoretical calculations are employed to elucidate the dual-ion storage mechanism. This work provides an effective strategy for designing POPs with high-capacity and high-rate for OCMs.