Graphdiyne: A Promising Catalyst-Support To Stabilize Cobalt Nanoparticles for Oxygen Evolution

Graphdiyne (GDY), with highly pi-conjugated structure of sp(2)- and sp-hybridized carbons, has recently appeared as an allotropic form of carbon nanomaterials. However, the application of this material is far behind its sister graphene. Herein, we attempt to use GDY as catalyst-support to stabilize cobalt nanoparticles for oxygen evolution, which is considered as the bottleneck for water splitting. In terms of close interaction between metal ions and alkyne pi-conjugated networks, the self-supported electrode is made in situ by a facile chemical reduction of Co2+ salt precursor in aqueous solution. The prepared 3D Cu@GDY/Co electrode shows high OER electrocatalytic activity with a small overpotential of nearly 0.3 V and a large unit mass activity of 413 A g(-1) at 1.60 V vs RHE. In the course of 4 h electrolysis, the electrode maintains the relatively constant current density. Our results indicate that the GDY is a promising catalyst support to stabilize metal NPs for oxygen evolution.