In-situ growing nanowires on biomass corn pods as free-standing electrodes with low surface reaction barrier for Li-, Al-, and Na-ion batteries

Biomass materials have received extensive attention for energy-storage due to low cost and specific structures. Here, a cost-effective carbonaceous material is prepared from biomass corn pod which is commonly considered as a waste, then CuCo2O4 nanowires are in-situ grown on the surface to form a three-dimensional free-standing electrode for several types of secondary batteries. The porous nanowires accommodate the volumetric change, which is beneficial for the stability; and low surface reaction barrier of the composite is verified by using galvanostatic intermittent titration technique (GITT) analysis. When using as a Li-ion battery anode, the CuCo2O4 nanowires/corn pod displays a capacity of 887 mAh/g after 250 cycles at 0.2 A/g, and the Coulombic efficiency exceeds 99.7 %. Under -10 degrees C and 45 degrees C, the capacities remain 726 and 700 mAh/g after 120 cycles, respectively. High rate-performance is achievable after three rounds of measurements. The low-cost free-standing electrode is also suitable for different battery types, displaying high performances as Al-ion battery cathode and Na-ion battery anode, which indicate a potential for engineering high-valuable energy-storage systems.