Controllable assembly of nitrogen-doped mesoporous carbon with different pore structures onto CNTs for excellent lithium storage

Mesoporous carbon nanomaterials have shown a great application potential in energy storage and conversion fields due to their outstanding conductivity, tunable pore structure, and good chemical stability. Nevertheless, how to accurately control the pore structure, especially directly assembling the mesoporous carbon onto different substrates remains a big challenge. Herein, we have successfully assembled two kinds of highly nitrogen-doped mesoporous carbon onto carbon nanotubes (NMC/CNTs) based on a facile cooperative assembly process assisted by triblock PEO₂₀PPO₇₀PEO₂₀ (P123) and PEO₁₀₆PPO₇₀PEO₁₀₆ (F127) copolymers. The experimental results indicate that the P123/F127 mass ratio has a profound effect on the pore structure, leading to the formation of NMC/CNTs composites with spherical pore structure (S-NMC/CNTs) and cylindrical pore structure (C-NMC/CNTs). In virtue of fast electron/ion transfer kinetics, the as-prepared S-NMC/CNTs anode demonstrates an excellent electrochemical performance for lithium-ion batteries, and it delivers a high reversible capacity of 588.1 mAh∙g⁻¹ at the current of 0.1 A∙g⁻¹ after 100 cycles, along with a superior cycling stability. Specifically noted, the controlled assembly route developed in our work can also be applied to other support materials with different structures and compositions.