Nitrogen-doped biomass carbon fibers with surface encapsulated Co nanoparticles for electrocatalytic overall water-splitting.

N-Doped biomass carbon fibers with surface encapsulated Co nanoparticles (Co/N-BCFs) are prepared by the in situ structure-directing effect of the Co-complex formed with 2,2-bipyridine. An electrolyzer equipped with a Co/N-BCFs electrode couple only needs a voltage of 1.31 V at 10 mA cm -2 for overall water-splitting, which is better than that of an integrated RuO 2 and Pt/C couple.