Free-Standing Dendritic Nanostructured Co/CNT/Carbon Nanofiber Composites for Efficient Water Splitting in Alkaline Media

Exploring highly efficient three-dimensional (3D) nanoarchitecturesfor H-2 and O-2 evolution reaction (HER and OER)has received tremendous interest. Here, a binder-free free-standingcobalt/bamboo-shaped carbon nanotube/carbon nanofiber (Co/CNT/CNF)film was prepared based on electrospinning, followed by thermal treatment.The synergistic effect between Co cores, CNT shells (5 nm), and CNFskeletons endows the as-prepared Co/CNT/CNF with a 3D porous dendriticnanostructure. Therefore, the unique Co/CNT/CNF film demonstratesprominent HER (overpotential = 129 mV) and OER (overpotential = 162mV) catalysis behavior at 10 mA cm(-2). Meanwhile,the as-prepared Co/CNT/CNF film displays excellent overall water splittingactivity as well as durability (at least 40 h both under 10 and 40mA cm(-2)). Moreover, the facile electrospinning followedby the thermal treatment approach is economically practical for flexiblefilm production, which has great potential for industrial applicationin water splitting technology.