Yolk-Shell MnO@ZnMn2 O4 /N-C Nanorods Derived from α-MnO2 /ZIF-8 as Anode Materials for Lithium Ion Batteries.

Abstract

Manganese oxides (MnOx ) are promising anode materials for lithium ion batteries, but they generally exhibit mediocre performances due to intrinsic low ionic conductivity, high polarization, and poor stability. Herein, yolk-shell nanorods comprising of nitrogen-doped carbon (N-C) coating on manganese monoxide (MnO) coupled with zinc manganate (ZnMn2 O4 ) nanoparticles are manufactured via one-step carbonization of α-MnO2 /ZIF-8 precursors. When evaluated as anodes for lithium ion batteries, MnO@ZnMn2 O4 /N-C exhibits an reversible capacity of 803 mAh g-1 at 50 mA g-1 after 100 cycles, excellent cyclability with a capacity of 595 mAh g-1 at 1000 mAg-1 after 200 cycles, as well as better rate capability compared with those non-N-C shelled manganese oxides (MnOx ). The outstanding electrochemical performance is attributed to the unique yolk-shell nanorod structure, the coating effect of N-C and nanoscale size.