(625f) Metal Nanoparticles Directed NiCo2O4 Nanostructure Growth on Carbon Substrates with Large Capacitance

The rapid development of portable flexible electronics requires significant advancement of energy storage materials in terms of energy and power density, mechanical strength, flexibility and durability. Current techniques focus on developing conductive carbon substrate and subsequently coating pseudoactive nanostructures on carbon to achieve high energy/power density. However, most of the decorated pseudoactive nanostructures meet interfacial failure during long term cycling tests and results in significant energy drop after certain cycles. Here, we developed a novel two-step approach to manufacture electroactive nanocomposites with excellent interfacial properties. Nanoparticles were introduced to promote carbon graphitization in the first annealing process and further served as “seeding” material for NiCo₂O₄ nanostructure growth in the second step. With the “bridging” effect of the metal nanoparticles, excellent interface between NiCo₂O₄ and graphitized carbon fabric are obtained. The electrodes show large capacitance of >700 F/g. More important, excellent cycling performance with >90% retention over 10000 cycles are achieved. This two-step method provides a general and promosing approach to synthesize hierarchical nanostructures for advanced energy storage devices.