Among
various organic cathode materials, CO group-enriched
structures have attracted wide attention worldwide. However, small
organic molecules have long suffered from dissolving in electrolytes
during charge–discharge cycles. π-Conjugated microporous
polymers (CMPs) become one solution to address this issue. However,
the synthesis strategy for CMPs with rich CO groups and stable
backbones remains a challenge. In this study, a novel CMP enriched
with CO units was synthesized through a highly efficient Diels–Alder
reaction. The as-prepared CMP exhibited a fused carbon backbone and
a semiconductive characteristic with a band gap of 1.4 eV. When used
as an organic electrode material in LIBs, the insoluble and robust
fused structure caused such CMPs to exhibit remarkable cycling stability
(a 96.1% capacity retention at 0.2 A g–1 after 200
cycles and a 94.8% capacity retention at 1 A g–1 after 1500 cycles), superior lithium-ion diffusion coefficient (5.30
× 10–11 cm2 s–1), and excellent rate capability (95.8 mAh g–1 at
1 A g–1). This study provided a novel synthetic
method for fabricating quinone-enriched fused CMPs, which can be used
as LIB cathode materials.