Synthesis of peanut-shaped porous ZnMn2O4 microparticles with enhanced lithium storage properties

Abstract

Peanut-shaped porous ZnMn2O4 microparticles assembled by nanoparticles have been prepared by annealing treatment of the Zn1/3Mn2/3CO3 precursors synthesized via a solvothermal reaction in water-triethanolamine binary solvent. The volume ratio of water to triethanolamine remarkably affects the shape and particle size of the carbonate precursor. The monodisperse ZnMn2O4 microparticles with a length of ca. 1 µm and a width of ca. 0.5 µm are constructed by many interlinked nanoparticles with a size of ca. 50–90 nm. As anode materials for Li-ion batteries, the peanut-shaped ZnMn2O4 microparticles display an outstanding rate capability with a lithiation capacity of 579 mAh g−1 at 4 A g−1 and long-cycle performance with a reversible capacity of 797 mAh g−1 after 700 cycles at 0.5 A g−1. The significantly enhanced lithium storage properties benefit from the desired porous micro-/nanostructures with suitable particle sizes, which enable the fast diffusion for lithium ions and the structural integrity of the electrode upon cycling.