The electrochemical performance of La0.6Sr0.4Co1-x Ni x O3 perovskite catalysts for Li-O2 batteries

Ni doped perovskite oxides La0.6Sr0.4Co1-x Ni (x) O-3 (x = 0, 0.05, 0.1) have been synthesized by a dry gel combustion method using citric acid and EDTA (ethylene diamine tetraacetic acid) as complex agent. The Li-O-2 batteries on the basis of the La0.6Sr0.4Co1-x Ni (x) O-3 perovskite nanoparticles and non-aqueous electrolytes were also fabricated and measured. The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity of as-prepared electrodes were measured by cyclic voltammetry (CV) curves. The peak current increased in the order of pure Super P, La0.6Sr0.4CoO3, La0.6Sr0.4Co0.95Ni0.05O3, and La0.6Sr0.4Co0.9Ni0.1O3. The electrochemical impedance spectroscopy (EIS) measurements revealed that La0.6Sr0.4Co1-x Ni (x) O-3 catalyst could restrain the increase of impedance during discharge process and promote the decomposition of discharge products during charge process. La0.6Sr0.4Co0.95Ni0.05O3 and La0.6Sr0.4Co0.9Ni0.1O3 catalysts displayed enhanced performances compared with La0.6Sr0.4CoO3 catalyst. The initial capacity of batteries using La0.6Sr0.4Co0.95Ni0.05O3 and La0.6Sr0.4Co0.9Ni0.1O3 as the cathode catalyst displayed enhanced performances compared with La0.6Sr0.4CoO3 catalyst, which was in agreement with the trend of CV curves.