Confined Growth of Highly Ordered Metal Atomic Arrays for Seawater Oxidation.

Metal atom catalysts have been among the most important research objects due to their specific physical and chemical properties. However, precise control of the anchoring of metal atoms is still challenging to achieve. Cobalt and iridium atomic arrays formed sequentially ordered stable arrays in graphdiyne (GDY) triangular cavities depending on their intrinsic chemical properties and interactions. The success of this method was attributed to multifunctional integration of GDY, enabling selective growth from one to several atoms and various atomic densities. The bimetallic atom arrays show several advantages resulting from reducibility of acetylene bonds, space limiting effect, incomplete charge transfer between GDY and metal atoms, and sp-C hybridized triple bond skeleton. This well-designed system exhibits unprecedented oxygen evolution reaction (OER) performance with a mass activity of 2.6 A mg cat. -1 at a low overpotential of 300 mV, which is 216.6 times higher than the state-of-the-art IrO 2 catalyst, and long-term stability.