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Development of N-doped carbon nanotubes(CNTs)with a hollow structure is extremely important for its application to electrochemical catalysis and energy storage.Here we demonstrate a facile synthesis of N-doped CNTs from direct pyrolysis of a mixture of nickel salt(or nickel/cobalt salts),glucose and dicyandiamide,in which both the N-doping process and the synthesis of carbon nanotubes are completed.The resulting hybrid N-C composites with high N doping contents show an emblematic tubular morphological structure revealing a hollow interior.Nickel salt is found to be an essential growth catalyst of these N-doped CNTs and the as-obtained tubular structure is about 27 nm in diameter in the presence of nickel and cobalt salts.All the as-prepared catalysts display a comparable onset potential and high current density for ORR compared to Pt/C both in acidic and in alkaline media.Ni-Co/C-N-HT catalyst even displays an extremely high ORR limiting current density of 7.2 mA·cm-2@1600rpm in acidic media,which is more than 1.3 times larger than the Pt/C.