Rational design to manganese-doped amorphous tetra-metallic oxides as efficient catalysts for Li[sbnd]O2 batteries

Abstract

Ions doping engineering is considered an effective strategy to modulate the catalytic activity of multi-metallic oxides as efficient oxygen electrodes for lithium‑oxygen (LiO2) batteries. In this article, amorphous tetra-metallic (Fe-Co-Ni-Mn) oxides modulated by varying manganese content were synthesized by co-precipitation followed by calcination, which could offer large quantities of catalytically active sites and good synergistic effect between the redox pairs. Notably, the amorphous structure with a higher specific surface area leads to the exposure of a large amount of active sites. Benefiting from the above advantages, the LiO2 batteries deliver a low voltage gap of 0.84 V, a considerable initial specific capacity of 13,675 mAh g−1 at the current density of 100 mA g−1, and superior long-term cycling for 910 h without significant voltage attenuation. Our work provides new insight into a facile and promising approach to the fabrication of highly active catalytic oxygen cathode and demonstrates that the synergistic interaction between the abundant valence-changeable metals cations in designing tetra-metallic oxides is a valuable strategy to achieve high-efficiency electrocatalyst for LiO2 batteries.