Synthesizing New Ternary Nitrides with Guidance from In Situ X-Ray Diffraction

Ternary nitrides are an important class of functional solids, most famous for underpinning high-efficiency light emitting diodes. These materials are composed of nitrogen along with two other elements (e.g., In<i>_x</i>Ga_1-<i>x</i>N for those light emitting diodes). However, making these materials is challenging, in part owing to the low reactivity of elemental nitrogen gas (N₂), and the propensity for nitrogen-containing solids to decompose at elevated temperatures (releasing N₂). Metathesis reactions (also known as ion exchange reactions) can help us overcome these challenges and keep nitrogen in the solid state to synthesize new ternary nitrides. For example, we have recently discovered that starting from lithium-containing precursors (e.g., Li₆WN₄), we can conduct metathesis reactions with Zn<i>X</i>₂ salts (<i>X</i> = F, Cl, Br) to synthesize new Zn ternary nitrides (e.g., Zn₃WN₄). This presentation will focus on our recent work studying these kinds of metathesis reactions using <i>in situ</i> X-ray diffraction, with an eye towards generalizing this synthesis approach to accelerate materials discovery.