Spinel ZnMn2O4 Nanocrystal-Anchored 3D Hierarchical Carbon Aerogel Hybrids as Anode Materials for Lithium Ion Batteries

To improve the electrochemical performance of spinel ZnMn2O4, i.e., its limited specific capacity, cycling performance, and rate properties, owing to its inherent poor electrical conductivity and large volume changes during lithiation and delithiation processes, spinel ZnMn2O4 nanocrystals are anchored into a three dimensional (3D) porous carbon aerogel (CA) through a facile solution immersion chemical route. The designed 3D spinel ZnMn2O4/CA hybrids display the advantages of both spinel ZnMn2O4 and porous CA: enormous interfacial surface area, connected 3D framework, abundant porosity and high electron transport properties of CA, and electrochemical properties of nanostructured spinel ZnMn2O4 oxide materials. The synthesized novel ZnMn2O4/CA hybrids display a significantly improved electrochemical performance, with a high reversible specific capacity, and high-rate capability, as well as an excellent cycling performance, superior to that of previously reported ZnMn2O4-based materials. After 50 cycles, the 50% ZnMn2O4/CA hybrid displays a reversible capacity of 833 mAh g(-1) at a current density of 100 mAg(-1), much higher than the theoretical capacity of 784 mAh g(-1) for pure spinel ZnMn2O4 materials, corresponding to a Coulombic efficiency of 99.9%. The greatly improved cycle stability, specific capacity, and high rate performance of the ZnMn2O4/CA hybrids can be attributed to the synergistic interaction between spinel-structured ZnMn2O4 nanoparticles and the 3D interconnected porous CA matrix.