Three-dimensional network macro-porous cobalt oxide as catalyst for Li–O2 cells

Li–O 2 cell is considered as an ideal choice for the electric vehicles due to its high energy density , but is now suffering from the large charge polarization and low practical capacity. In this context, three-dimensional network macro-porous CoO synthesized via a sol–gel method is applied as an efficient catalyst in Li–O 2 cells to alleviate this situation. Compared to KB (Ketjen black EC600JD) based cells, the CoO/KB based cell exhibits much improved electrochemical performance at various current densities, including flatter discharge/charge plateau, lower polarization and higher specific capacity. In addition, the CoO/KB based cell maintains the discharge capacity up to 4500 mAh g −1 CoO/KB after being cycled at 0.1 mA cm −2 for 16 days under O 2 atmosphere. This excellent electrochemical performance is attributed to the high catalytic activity and abundant macro-pores of our home-made CoO. This strategy of designing CoO might be a feasible way to obtain the Li–O 2 cell with low polarization and high capacity.