Conjugated microporous polyimides (CMPs) have been emerging as the promising electrode materials for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs) owing to their low cost, tunable structures, envi-ronmental benefit, and high porosity. However, the low intrinsic conductivity, poor structural stability and sluggish diffusion kinetics have hindered their further applications. Herein, a novel conjugated microporous polyimide trapped by multi-walled carbon nanotubes (TAPBA-NTCDA@MWCNTs) as cathodes for SIBs/LIBs have been prepared by in situ polycondensation. The addition of MWCNTs profits greatly in conductivity and structural stability of electrode materials. Consequently, when explored as cathode materials for SIBs, TAPBA-NTCDA@MWCNTs exhibits the good reversible specific capacity, predominant rate capability and ultra-long cycling stability. Moreover, the reaction mechanism and outstanding reversibility are investigated by the detailed ex-situ XPS/FT-IR/SEM analysis. Finally, the cathode also delivers an excellent lithium storage perfor-mance. In view of the outstanding cycle stability and such simple synthetic route, this work perhaps provides an effective strategy to fabricate high-performance conjugated microporous polyimide-based cathodes for energy storage and conversion devices.

Conjugated organic polymers have been deemed as one type of the most promising electrode materials for lithium-ion batteries (LIBs) due to their structural diversity and functional designability. However, the poor conductivities and limited redox-active sites of these polymers severely impede their applications in LIBs. Herein, four novel pyrene-4,5,9,10-tetraone (PTO)-based polymers (namely PTO-Bz, PTO-Py, PTO-Pm, and PTO-Tz) were designed and synthesized as cathode materials with high electrochemical activity (four redox sites of PTO units) and superb structural/chemical stability. By changing the N content in aryl linkers, the electronic conduction and transportation of polymer structures could be readily adjusted, leading to enhanced electrochemical activity. As a result, the optimal PTO-Py polymer displays high electronic conductivity and enhanced pseudocapacitive behavior compared with the other samples. When evaluated as a cathode for LIBs, the PTO-Py electrode shows a high lithium storage performance of 220.4 mA h g-1 with an ICE of 97.0% at 0.1 A g-1, superior rate performance (153.1 mA h g-1 at 10 A g-1), and excellent cycling abilities (70.8% capacity retention over 2000 cycles at 1.0 A g-1). In addition, ex situ FT-IR and XPS analyses were also carried out to further understand the Li+ storage mechanism. This work unveils an efficacious strategy to exploit high-performance conjugated organic polymer electrodes for energy storage systems. Four novel conjugated pyrene-4,5,9,10-tetraone (PTO)-based polymers with different aryl derivatives as linking units were prepared to explore the effect of electronic structures on the electrochemical properties of lithium-ion batteries (LIBs).