Self-growth of nitrogen-doped carbon nanotube composites using MOFs as templates and their application in Li-O2 batteries.

The excessively high polarization potential during the charge and discharge process of Li-O2 batteries is one of the important factors restricting its development. Selecting a catalyst with bifunctional catalytic activity to improve the ORR and OER reaction kinetics is an important measure to reduce polarization and improve rate performance. In this study, Co-BTC was employed as a template to construct Ni-containing complexes via a hydrothermal process. During subsequent pyrolysis with dicyandiamide as the nitrogen source, nitrogen-doped carbon nanotubes were self-catalytically grown. The resulting structure effectively suppresses the charge-discharge polarization of Li-O2 batteries. When used as a cathode catalyst, Ni/Co2N@NCNTs batteries can stably cycle 220 times, Ni@NCNTs can only cycle 70 times, and Co2N@NCNTs can only cycle 110 times.