One-dimensional graphene nanoribbons are attracting considerable attention due to their extraordinary electronic, magnetic, and optical properties, and have a wide range of applications, but have not attained full success owing to the lack of simple and efficient synthetic strategies. Here, we present a facile strategy for the synthesis of graphene nanoribbons by unraveling ultra-small carbon nanotubes. The armchair (2,2) carbon nanotubes with a theoretical diameter of 0.28 nm fabricated in the nanochannels of zeolite ZnAPO₄-11 (AEL) can be transformed into graphene nanoribbons by removing the AEL template through chemical treatment. The as-synthesized graphene nanoribbons are N-doped with a thickness of two- to seven-layers, have a width of 10–30 nm and length of >1 μm, and show high performance as an anode material for lithium ion batteries. Moreover, this strategy can be readily scaled up for practical applications requiring bulk quantities of graphene nanoribbons.