Surface Chemistry of Perovskite Oxynitride Photocatalysts: A Computational Perspective

Abstract

Perovskite oxynitrides are an established class of photocatalyst materials for water splitting. Previous computational studies have primarily focused on their bulk properties and have drawn relevant conclusions on their light absorption and charge transport properties. The actual catalytic conversions, however, occur on their surfaces and a detailed knowledge of the atomic-scale structure and processes on oxynitride surfaces is indispensable to further improve these materials. In this contribution, we summarize recent progress made in the understanding of perovskite oxynitride surfaces, highlight key processes that set these materials apart from their pure oxide counterparts and discuss challenges and possible future directions for research on oxynitrides.

Thin‐Film Oxynitride Photocatalysts for Solar Hydrogen Generation: Separating Surface and Bulk Effects Using Synchrotron X‐Ray and Neutron‐Based Techniques

“…The selection of specific grain facets during the oxynitride particles formation may allow achieving considerably enhanced PEC properties. [61][62][63][64]…”

Probing the Polaronic Landscape in Bi4TaO8X Perovskite Oxyhalides Photocatalysts

“…In addition to these, the photocatalyst should exhibit low electron and hole recombination rates. After years of research, various materials such as perovskite oxynitrides (e.g., BaTaO 2 N and SrTaO 2 N) have been found to exhibit promising photoelectrochemical activity under visible light. − However, these materials are prone to self-oxidation during the reaction due to the oxidation of N 3– by the photogenerated holes. An alternative is the Sillén–Aurivillius perovskite oxyhalides Bi 4 TaO 8 X (X = Cl, Br), which exhibit high stability and efficiency under visible light. − These perovskite oxyhalides are characterized by the alternating stacking of Aurivillius perovskite blocks and Sillén blocks (see Figure ).…”