Growth and characterization of single-crystalline oxynitride materials for solar fuels production

Abstract

A complete photoelectrochem. device requires many components, all working together at optimal efficiencies for prolonged periods of time. Unfortunately, to date the performance and stability of many of the available materials is less than desired, esp. under the extreme alk. or acidic environments required for a com. viable solar fuels platform. Recent reports have identified transition metal oxynitrides as one of the few classes of semiconductor materials capable of direct overall water splitting under visible-light irradn. However, poor materials quality, low performances (<1%) and modest stabilities still hinder their in-depth study. Here, we present our recent work on the development of new synthetic methods for the prodn. of high-quality singlecrystals of a series of perovskite-type oxynitrides, as well as their application as efficient photoanodes for water oxidn. In addn., we cover the effects that various co-catalysts and surface protection layers have on the electronic band structure, activity, and stability of these systems.