AUTHOR=Li Lingjun , Yao Qi , Liu Jiequn , Ye Kaibo , Liu Boyu , Liu Zengsheng , Yang Huiping , Chen Zhaoyong , Duan Junfei , Zhang Bao 

TITLE=Porous Hollow Superlattice NiMn2O4/NiCo2O4 Mesocrystals as a Highly Reversible Anode Material for Lithium-Ion Batteries

JOURNAL=Frontiers in Chemistry

VOLUME=6

YEAR=2018

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2018.00153

DOI=10.3389/fchem.2018.00153

ISSN=2296-2646

ABSTRACT=<p>As a promising high-capacity anode material for Li-ion batteries, NiMn<sub>2</sub>O<sub>4</sub> always suffers from the poor intrinsic conductivity and the architectural collapse originating from the volume expansion during cycle. Herein, a combined structure and architecture modulation is proposed to tackle concurrently the two handicaps, via a facile and well-controlled solvothermal approach to synthesize NiMn<sub>2</sub>O<sub>4</sub>/NiCo<sub>2</sub>O<sub>4</sub> mesocrystals with superlattice structure and hollow multi-porous architecture. It is demonstrated that the obtained NiCo<sub>1.5</sub>Mn<sub>0.5</sub>O<sub>4</sub> sample is made up of a new mixed-phase NiMn<sub>2</sub>O<sub>4</sub>/NiCo<sub>2</sub>O<sub>4</sub> compound system, with a high charge capacity of 532.2 mAh g<sup>−1</sup> with 90.4% capacity retention after 100 cycles at a current density of 1 A g<sup>−1</sup>. The enhanced electrochemical performance can be attributed to the synergistic effects of the superlattice structure and the hollow multi-porous architecture of the NiMn<sub>2</sub>O<sub>4</sub>/NiCo<sub>2</sub>O<sub>4</sub> compound. The superlattice structure can improve ionic conductivity to enhance charge transport kinetics of the bulk material, while the hollow multi-porous architecture can provide enough void spaces to alleviate the architectural change during cycling, and shorten the lithium ions diffusion and electron-transportation distances.</p>