Time-resolved operando XAS-XRD studies to correlate phase evolution and catalytic activity of Li14Cr2N8O during NH3 decomposition

Studies on alternatives to Ru-based catalysts are crucial for NH3 decomposition. These include earth abundant 3d metals, where Cr is underexplored as it strongly binds to N2 leading to high energy barriers. Our recent study, however, has found that Li14Cr2N8O exhibits promising activity. This is among the earliest to focus on Cr(VI) while prior works highlight low valent Cr. Initial diffraction data, however, revealed the emergence of mixed Cr-phases during reaction so the measured activity cannot be fully associated to Li14Cr2N8O. To identify active phases and conditions where they were formed, operando studies are needed. Our initial data also indicated the possibility of the creation of mixed crystalline-amorphous phases, further driving the need for a combined approach on describing Li14Cr2N8O during reaction. We intend to perform operando XAS-XRD at BM31-SNBL to decipher the identity of these active phases and the conditions (e.g., T) that impact their emergence.