Nano carbon material composites significantly enhance the performance of lithium manganese iron phosphate (LMFP) cathode materials. This study investigates the self-catalytic growth mechanism of highly conductive carbon nanotubes (CNTs) on bare LMFP particles via chemical vapor deposition (CVD), focusing on the influence of particle size and crystallographic orientation. It is found that the Fe3C particles formed on static solvothermal synthesized LMFP nanoplates with high [010] orientation were effective to catalyze the generation of CNTs. Diverse CVD durations produced CNTs coatings with varying structures to impact electrochemical properties of final products. The MP-L/CNTs-2 sample, with 3.6 wt% carbon, showed the highest reversible capacity of 158 mAh g−1 at 1 C with 99.3 % capacity retention after 400 cycles, after 3000 cycles at 10 C, the retention rate was 74.5 %. In contrast, LMFP synthesized via solid-phase method (MP-S/C) only formed a carbon film on the surface and delivered 143 mAh g−1 at 1 C (97.6 % retention after 400 cycles) with prominent capacity loss at 10 C. This study provides new insights into the self-catalytic growth mechanism of CNTs to promote ion-electron conductivity and structural stability of LMFP materials, thus improving kinetic property and cycling stability for high-performance lithium-ion batteries.
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