Ru-impregnated needle-like NiCo2O4 embedded in carbon textiles as O2 electrode for a flexible Li–O2 battery

Abstract The synergistic effect between noble metal and spinel-type compounds is beneficial for enhancing the electrochemical performance in a Li–O2 battery. Herein, Ru-impregnated needle-like NCO embedded in porous carbon textiles (CTs) (x wt% Ru@NCO/CTs (x = 0, 0.5, 1, 2, and 5)) is applied as a flexible and binder-free O2 electrode for Li–O2 batteries. The NCO structure can benefit to the Li+ migration, O2 diffusion, and Li2O2 accommodation. The Ru nanoparticles can promote OER and ORR reaction kinetics and lower the overpotential. A flexible Li–O2 cell with 1 wt% Ru@NCO/CTs exhibits a good cyclic stability of 360 cycles with an overpotential of 0.78 V at a constant current density of 200 mA/g, a considerable rate performance, a high reversibility with the Li2O2 formation and its reverse decomposition, and a good flexibility stability under bending and twisting at the different conditions. This work can contribute to the development of electrode material and its architecture design for portable and wearable devices.