A Simple Descriptor toward Optimizing Electrocatalytic N Oxidation to HNO Performance over Graphene-Based Single-Atom Catalysts.

Single-atom catalysts (SACs) exhibit tremendous advantages in the electrochemical N oxidation reaction (ENOR) to HNO, which is an eco-friendly alternative to the synthesis of conventional industrial nitric acid and nitrates, but methods to rationally design and rapidly screen high-efficiency ENOR SACs are unclear. Herein, taking pyridinic nitrogen-doped graphene-supported SACs as an example, a simple descriptor has been proposed to evaluate the ENOR performance through systematically constructing a surface reaction phase diagram. This descriptor is comprised of merely the geometric information and inherent atomic properties (occupied d electron number, electronegativity, and coordinate number) that can accurately predict the activity and selectivity of ENOR, independent of DFT simulations.