Cobalt Sulfide Nanosheet/Graphene/Carbon Nanotube Nanocomposites as Flexible Electrodes for Hydrogen Evolution

Flexible three‐dimensional (3D) nanoarchitectures have received tremendous interest recently because of their potential applications in wearable electronics, roll‐up displays, and other devices. The design and fabrication of a flexible and robust electrode based on cobalt sulfide/reduced graphene oxide/carbon nanotube (CoS 2 /RGO‐CNT) nanocomposites are reported. An efficient hydrothermal process combined with vacuum filtration was used to synthesize such composite architecture, which was then embedded in a porous CNT network. This conductive and robust film is evaluated as electrocatalyst for the hydrogen evolution reaction. The synergistic effect of CoS 2 , graphene, and CNTs leads to unique CoS 2 /RGO‐CNT nanoarchitectures, the HER activity of which is among the highest for non‐noble metal electrocatalysts, showing 10 mA cm −2 current density at about 142 mV overpotentials and a high electrochemical stability.