Stereological 3D modeling of nano-scale catalyst particles using TEM projections

Catalysis, particularly heterogeneous catalysis, is crucial in the chemical industry and energy storage. Approximately 80% of all chemical products produced by heterogeneous catalysis are produced by solid catalysts, which are essential for the synthesizing of ammonia, methanol, and hydrocarbons. Despite extensive use, challenges in catalyst development remain, including enhancing selectivity, stability, and activity. These effective properties are influenced by the nanoscale morphology of the catalysts, whereby the size of the nanoparticles is only one key descriptor. To investigate the relationship between nanoparticle morphology and catalytic performance, a comprehensive 3D analysis of nano-scale catalyst particles is necessary. However, traditional imaging techniques for a representative recording of this size range, such as transmission electron microscopy (TEM), are mostly limited to 2D. Thus, in the present paper, a stochastic 3D model is developed for a data-driven analysis of the nanostructure of catalyst particles. The calibration of this model is achieved using 2D TEM data from two different length scales, allowing for a statistically representative 3D modeling of catalyst particles. Furthermore, digital twins of catalyst particles can be drawn for the stochastic 3D model for virtual materials testing, enhancing the understanding of the relationship between catalyst nanostructure and performance.