Overall water electrolysis on a graphdiyne-iron oxyhydroxide heterostructure

Abstract

Water electrolysis provides an effective method for energy efficient hydrogen production. The challenge in this field is how to synthesize electrocatalysts with high activity and stability in water electrolysis reactions. Herein, a new heterostructure of graphdiyne-iron oxyhydroxide was synthesized by controlled growth of GDY films on the surface of FeOOH nanowires (FeOOH@GDY). An interface structure with an electron-donor (GDY) and electron-acceptor (Fe) was formed, which showed the obvious incomplete charge transfer between GDY and Fe atoms at the interfaces. This produces infinite active sites which guarantee excellent catalytic activity. The GDY grown on the surfaces of oxyhydroxides endows the electrocatalyst with high stability. These unique and fascinating properties make FeOOH@GDY show excellent catalytic activities toward overall water splitting (OWS) with a small cell voltage of 1.43 V at 10 mA cm⁻² under ambient conditions and excellent long-term stability.