Simple template fabrication of porous MnCo₂O₄ hollow nanocages as high-performance cathode catalysts for rechargeable Li-O₂ batteries

Porous MnCo₂O₄ hollow nanocages have been fabricated via a simple template method using carbon spheres as a template. The hydrophilic surface of carbon spheres can adsorb Mn²⁺ and Co²⁺ ions simultaneously to form Mn,Co-adsorbed carbon spheres. The calcination of Mn,Co-adsorbed carbon spheres can result in porous hollow nanocages of MnCo₂O₄. The MnCo₂O₄ hollow nanocages are built by nanoscale MnCo₂O₄ crystals. Because of the unique porous hollow nanostructures, the resulting MnCo₂O₄/KB cathode shows an efficient electrocatalytic performance in LiTFSI/TEGDME electrolyte-based Li-O₂ batteries. The MnCo₂O₄ hollow nanocages as the cathode catalysts can deliver better performance during the discharge/charge processes and good cycle stability compared with that of the pure KB carbon. The preliminary results manifest that porous MnCo₂O₄ hollow nanocages are promising high-performance cathode catalysts for Li-O₂ batteries. This template technique is a simple, general, low-cost and controllable method and can be extended to prepare other transition metal oxide hollow nanostructures. (paper)