(9a) Reducing Precious Metal Loading Using Metal Nitride Supports for Water Electrolysis

Hydrogen (H₂) plays a critical role in modern society and water electrolysis represents a promising pathway to produce green H₂. However, water electrolysis in acidic electrolyte is hindered by the need for precious metal electrocatalysts, such as platinum (Pt) for the hydrogen evolution reaction (HER) and iridium (Ir) for the oxygen evolution reaction (OER). Transition metal nitrides (TMNs) are a class of earth-abundant materials that can be used as the catalyst supports to reduce the loading of precious metals, creating opportunities for more cost-effective HER and OER catalysts. In this talk we will present our results on Pt/TMN and Ir/TMN electrocatalysts for HER and OER, respectively. We will discuss our combined approaches of ultrahigh vacuum experiments and density functional theory calculations on well-characterized model surfaces, electrochemical measurements over the same model surfaces and the corresponding powder electrocatalysts, and in-situ characterization using synchrotron-based techniques.