Y.J. Ding, Y.C. Huang, Y.J. Li, T. Zhang*, Z.-S. Wu*
SmartMat, 2022, 1-11.
DOI: 10.1002/smm2.1150 [PDF]
The realization of high-efficiency, reversible, stable and safe Li-O2batteries is severely hindered by the large overpotential and side reactions, especially at high rate conditions. Therefore, rational design of cathode catalysts with high activity and stability is crucial to overcome the terrible issues at high current density. Herein, we report a surface engineering strategy to adjust the surface electron structure of boron (B) doped PtNi nanoalloy on carbon nanotubes (PtNiB@CNTs) as an efficient bifunctional cathodic catalyst for high-rate and long-life Li-O2batteries. Notably, the Li-O2batteries assembled with as-prepared PtNiB@CNTs catalyst exhibit ultrahigh discharge capacity of 20510 mAh g-1and extremely low overpotential of 0.48 V at a high current density of 1000 mA g-1, both of which outperform the most reported Pt-based catalysts recently. Meanwhile, our Li-O2batteries offer excellent rate capability and ultra-long cycling life of up to 210 cycles at 1000 mA g-1under a fixed capacity of 1000 mAh g-1, which is two times longer than those of Pt@CNTs and PtNi@CNTs. Furthermore, it is revealed thatsurface engineering of PtNi nanoalloyviadoping B can efficiently tailor the electron structure of nanoalloy and optimize the adsorption of oxygen species, consequently delivering excellent Li-O2battery performance. Therefore, this strategy of regulating the nanoalloy by doping non-metallic elements will pave an avenue for the design of high-performance catalysts for metal-oxygen batteries.
