Fe2O3 nanoparticles anchored on N-doped pinecone-based porous carbon as potential anode for potassium-ion battery

Fe2O3/carbon composites have received widespread attention as a potential anode material for lithium/sodium ion battery owing to its rich reserves, wide distribution, and environmental friendliness. However, studies on potassium-ion battery (PIB) have rarely been reported. Besides, majority carbon-based matrices are mainly focused on the utilization of synthetic carbons, which have a high cost and complicated synthesis process. In contrast, biomass-based carbon is inexpensive, environment-friendly, and abundant in terms of its precursor resources, making it a promising matrix. In this work, the dispersal of Fe2O3 nanoparticles on a N-doped pinecone-based porous carbon matrix (Fe2O3/NPC) was proposed as a simple and effective approach for improving the electrochemical performance of the Fe2O3 anode in potassium-ion battery. Fe2O3/NPC was prepared using a hydrothermal method, and the morphology of Fe2O3 was optimized by varying the reaction temperature. Compared with Fe2O3, NPC and Fe2O3/NPC prepared at different temperature, the Fe2O3/NPC-150 electrode exhibited an improved discharge capacity of 178.7 mAh·g−1 after 100 cycles at 50 mA·g−1 with good rate performance and the high capacity retention rate of 91.6% after 500 cycles. The improved electrochemical performance is attributed to the synergistic effect of small Fe2O3 nanoparticles and N-doped pinecone-based porous carbon. This strategy provides a simple, mild and low cost method for preparing iron based anode materials for potassium-ion battery, and also provides some guidances for large-scale industrial production.