Application of Parallel Characterization Methods in High- Throughput Catalyst Preparation and Development

Catalyst characterization plays an important role in developing catalytic materials because it helps to identify active catalytic phases or centers and to elucidate reaction mechanisms. Several characterization methods have been parallelized and successfully applied in the high-throughput workflow of catalyst development. We present characterization equipment developed at the Leibniz Institute for Catalysis and show applications in three research areas: (i) in catalyst synthesis for identifying suitable preparation conditions, (ii) in understanding factors governing catalytic performance for identifying structure-reactivity relationships, and (iii) in understanding catalyst deactivation for elucidating the deactivation mechanisms. 6-fold and 8-fold reactors are used for temperature programmed reduction (TPR), oxidation (TPO), desorption (TPD) and chemical titration experiments. TPR has been successfully applied for studying the reducibility of supported Ni-containing catalysts for CO2 reforming of CH4 and for investigating the interaction between metal oxide species and support materials. Chemisorption of H2 and CO2 has provided information about Ni dispersion and basic properties of said catalysts, and with TPO of spent catalysts coke formation was monitored. To prepare catalysts for visible-light induced water splitting, we studied the formation of nitrides and oxynitrides from oxides upon their temperature programmed treatment under a flow of ammonia. We also used 6-fold and 36-fold parallel reactors utilizing UV/vis catalyst analysis in reflectance mode to study changes in valence state and coordination of supported VOx during oxidative dehydrogenation of propane, and to follow coke formation during catalyst deactivation in non-oxidative dehydrogenation of propane.

Keywords: Ammonolysis, band gap, CO2 reforming of methane, diffuse reflectance UV/vis spectroscopy, dry reforming of methane, high throughput catalysis, high throughput characterization, high throughput experimentation, high-throughput synthesis, metal dispersion, mixed-metal oxynitrides, operando spectroscopy, parallel reactors, propane dehydrogenation, pulse experiments, steady-state isotopic transient kinetic analysis, temperature programmed desorption, temperature programmed oxidation, temperature programmed reactions, temperature programmed reduction, water splitting.