Synergizing Cobalt Ruthenium Alloy with Chromium Oxyhydroxide for Highly Efficient Electrocatalytic Water Splitting.

ABSTRACT

Constructing a coupling interface of multicomponents with different functions is of considerable importance for designing an advanced bifunctional water splitting electrode. Particularly, designing and developing alloy/oxyhydroxide-integrated electrodes have emerged as a tendency yet remain a considerable challenge. In this work, a novel 3D nanostructure electrocatalyst assembled from CoRu nanoalloy and CrOOH nanosheets (denoted as CoRu-CrOOH/NF) was directly grown on nickel foam via a successive hydrothermal method. The unique synergy in CoRu-CrOOH/NF heterostructures is not only conducive to strengthening charge transfer capability and accelerating the reaction kinetics but also favors the redistribution of charge within the interface, thus improving the electrocatalytic performance. In view of the above-mentioned points, the resultant CoRu-CrOOH/NF displays outstanding catalytic performance with overpotentials of 26 and 272 mV at 10 mA cm-2 for hydrogen evolution reaction (HER) and 50 mA cm-2 for oxygen evolution reaction (OER). Remarkably, the symmetrical two-electrode cell using CoRu-CrOOH/NF only acquires 1.47 V at 10 mA cm-2 in 1.0 M KOH, which is superior to many other state-of-the-art overall water-splitting electrocatalysts. This holistic work provides a new insight to designing alloy/oxyhydroxide-integrated electrodes for high-efficiency overall water splitting.