Limited by unsatisfactory mass diffusion and complex fabrication procedures, nanoporous carbons (NPCs) don't perform well, served as catalyst supports. Herein, utilizing nitrogen doped carbon nanotubes (NCNTs) as spacers of nitrogen-doped graphene-like carbon nanosheets (NGs), a 3D nanoarchitecture (Co@NCNT-NG-900) is fabricated via a facile and eco-friendly approach. Physical characterizations manifest that the in situ-formed NCNTs make for improving graphitic degree, NGs contribute to increasing the specific surface area and the level of N-doping, meanwhile, the spacers effects of NCNTs promote the formation of opened macropores, what's more, Co@NCNT-NG-900 mainly consists of three-dimensional macropores and oversized mesoporous (3D macro-/oversized mesoporous), unlike conventional NPCs. Benefiting from improved charge transfer rate, enhanced N-doping level and dominant 3D macro-/oversized mesoporous, Co@NCNT-NG-900 is evaluated as an ideal Pt support for methanol oxidation reaction (MOR) in acid and alkaline medium. This work provides a facile synthetic method for NPCs and sheds directive light into the research of efficient catalysts for MOR. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.