Dr. Jill Wenderott
Drexel University
Friday, April 10, 2026
12:00 Noon
Room 120 – Meyerhoff Chemistry Building
Host: Dr. Joseph Bennett
“Guiding mixed anion material synthesis with informed approaches”
Mixed anion materials, compounds containing multiple anions in single phases, offer broad opportunity for new and potentially superior functionalities. Notably, transition metal oxynitrides – like the molybdenum (Mo-O-N) and tantalum (Ta-O-N) systems – have been increasingly investigated for their tunable electronic and optical properties. Oxynitrides are often synthesized via ammonolysis, in which gaseous ammonia is supplied and reacts with oxide precursor powders at elevated temperatures. Synthesis of phase pure oxynitrides is nontrivial, however, and there are many mixed anion materials that have been computationally-predicted but not yet experimentally-realized. To meet the challenge of synthesizing novel mixed anion oxynitrides with controlled properties, we leverage informed synthetic approaches that include in situ studies and computation-experiment-coupled methods. In the first part of this talk, the reaction pathway to γ-MoO x N y illuminated via in situ powder X-ray diffraction is presented. Leveraging findings from in situ studies, exotic molybdenum bronze precursors are utilized to produce phase pure molybdenum oxynitrides at the lowest reaction temperatures and highest surface areas reported in literature to date, relevant for their application in catalysis. In the second part of this talk, the development of a framework for rapid assessment of synthesizability of inorganic compounds through a combination of the CALculation of PHAse Diagram (CALPHAD) approach and experimental validation is presented. The success of this computational-experimental feedback loop is demonstrated with tantalum oxynitride (β-TaON), which displays a narrow synthetic window highly dependent on temperature and reactive gas flow partial pressures. This knitting together of computational and experimental materials discovery and synthesis in a responsive feedback loop is promising for the realization and design of functional inorganic materials with targeted properties.