Graphdiyne ultrathin nanosheets for efficient water splitting

Abstract

Graphdiyne (GDY) is an emerging 2D carbon material that exhibits unusual structures and properties. Therefore, growing heterogeneous materials on the surface of GDY is very attractive to achieve efficient energy utilization. Here, a simple method for the controllable synthesis of ultrathin charge-transfer complexes (CTs) of nickel with terephthalic acid nanosheets on GDY is reported. This catalyst shows record-high oxygen evolution reaction (OER) activity with an overpotential of only 155 mV to deliver a current density of 10 mA cm−2 in an alkaline electrolyte. Density functional theory calculations reveals that a strong p–d coupling effect in the GDY–CT interface region enhances the overall electronic activity, resulting in fast reversible redox-switching with a low electron-transfer barrier. Experimental characterization confirms that GDY plays a key role in modulating the morphological and electronic structures to accelerate the OER rate. These findings are expected to contribute to the design of more efficient catalysts for the realization of efficient hydrogen energy technologies.