Pd<inf>3</inf>Co/MWCNTs composite electro-catalyst cathode material for use in lithium-oxygen batteries

The development of catalysts with high catalytic activity is needed to improve the sluggish reaction kinetics in Li-O<inf>2</inf> batteries. In this study, nano-sized alloy particles derived from metal precursors were employed as a bimetallic catalyst in a Li-O<inf>2</inf> cell, with their high activity and uniform distribution serving to enhance energy efficiency, cycle life, and capacity retention. A cell fabricated with a palladium-cobalt/multi-walled carbon nanotubes (Pd<inf>3</inf>Co/MWCNTs) electrode was able to stably reach 70 cycles, whereas cells with MnO<inf>2</inf>/KB and KB electrodes lasted only 17 and 10 cycles, respectively. During the first charging cycle, the cell with a Pd3Co catalyst exhibited a 200 mV lower overpotential than the cell with a MnO<inf>2</inf>/KB electrode, and a 490 mV lower overpotential than when a KB electrode was used. The Pd3Co/MWCNTs cell also demonstrated superior capacity retention of ∼94.5% (5^th cycle) and ∼88.7% (20^th cycle), with impedance analysis revealing an enhanced reversibility that confirms the improvement in cycle performance.