Single-Atom-Mediated Spinel Octahedral Structures for Elevated Performances of Li-Oxygen Batteries.

Li-oxygen batteries have attracted much attention due to its ultra-high theoretical specific capacity, but the discharge product Li 2 O 2 is easy to accumulate, leading to low battery stability. Here, we demonstrate a series of high-efficiency cathode catalysts of Co 3 O 4 loaded with single-atomic metals (M=Ru, Pd, Pt, Au, Ir). The single-atomic metal could substitute the central Co atom in the octahedral coordination structure and maintain the structural stability; benefiting from the electron promoter effect, rendering more highly active Co 3+ exposed, providing rich nucleation sites for Li 2 O 2 deposition. And the loaded M atoms could separate the active Co 3+ centers, thereby regulating the dispersion of Li 2 O 2 to obtained a sheet-like morphology, which could facilitate its decomposition in the subsequent charge cycle. Our work found that the single atoms could effectively modulate the active metal oxide with which it is coordinated, thus collectively boosting the catalytic performance.