Ni(II)-Based Porphyrin-Conjugated Microporous Polymers as Promising Anode for Lithium Storage.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Conjugated microporous polymers (CMPs) are promising electrode materials for lithium-ion batteries (LIBs) due to their stability and tunable structures.
• Optimizing capacity, rate performance, and cycling stability simultaneously in CMPs for LIBs remains a significant challenge.

Purpose of the Study:

• To design and synthesize a novel porphyrin-based CMP (NiP-CMP) with integrated electrochemically active sites.
• To achieve simultaneous optimization of capacity, rate performance, and cycling stability in LIBs using the engineered NiP-CMP.

Main Methods:

• Rational design of a porphyrin-based CMP (NiP-CMP) incorporating metal-N4 macrocycles and conjugated alkyne linkages.
• Fine-tuning polycondensation conditions to achieve a high specific surface area (1110 m² g⁻¹).
• Electrochemical characterization of NiP-CMP as an electrode material for LIBs.

Main Results:

• The synthesized NiP-CMP exhibits a high specific surface area, facilitating efficient ion diffusion and charge transport.
• NiP-CMP delivers a high specific capacity of ~702 mA h g⁻¹ at 0.1 A g⁻¹.
• The material demonstrates excellent rate capability (355 mA h g⁻¹ at 1 A g⁻¹) and long-term cycling stability.

Conclusions:

• The rationally designed NiP-CMP effectively resolves the electrode material 'trilemma' of capacity, kinetics, and durability.
• This work presents a viable design strategy for high-performance organic electrode materials in advanced energy storage applications.