Robust and facile strategy for tailoring CoMn2O4 and MnCo2O4 structures as high capacity anodes for Li-ions batteries

摘要

Two AB(2)O(4) spinel structures have been synthesized by alternating the A- and B-site atoms in the forms (MnCo2O4 and CoMn2O4) through implementing the low-cost co-precipitation technique. Structural investigation results indicated the pronounced phase transformation from cubic of MnCo2O4 to the tetragonal spinel of CoMn2O4, while no change in the crystallite size was detected in both compounds. The observed microstructure via FE-SEM revealed MnCo2O4 nanopatticles with cup-like crystal shape and the CoMn2O4 nanoparticles with bubble-like morphology were manifested. FT-IR results showed a significant shift towards larger wavelengths in the vibrational bands of metal-oxygen bonds of CoMn2O4. The CoMn2O4 electrode exhibited initial discharge capacity (similar to 1710 mAhg(-1)) higher than that of (similar to 1443 mAhg(-1)) for MnCo2O4 electrode when cycled at 100 mAg(-1) versus Li/Li+. The assembled MnCo2O4 cell delivered 58 mAhg(-1), while CoMn2O4 cell gained 92.3 mAhg(-1) of specific discharge capacity over 50 cycles of different current densities.