Se-doped carbon as highly stable cathode material for high energy nonaqueous Li-O2 batteries

Abstract

Hetero-doped carbon materials have been generally applied as the cathode materials for Li-O2 batteries due to the improved catalytic activity. However, they commonly suffer from performance fading because of carbon corrosion under harsh oxidative environments in Li-O2 batteries. Herein, an elegant cathode material for Li-O2 batteries is developed through doping Se in carbon. The results show that the Se-doped carbon cathode reveals 53% higher discharge capacity, decreased overpotential and superior rate capability. Structure evolution analysis and density functional theory calculation reveal that the products mainly grow via solution driven mechanism, which can better sustain discharge. Se-doped carbon cathode also presents high stability due to its prominent antioxidant ability, efficiently suppressing the side reaction and cathode passivation.