Penn Research Group

Professor Penn's research group encompasses four major areas:

1. Elucidating the fundamental aggregation and growth mechanisms - especially nonclassical crystal growth mechanisms - of inorganic nanoparticles.

2. Characterizing the reactivity of natural and synthetic nanoparticles in environmentally relevant conditions.

3. Characterizing the magnetic behavior of iron oxide nanoparticles (e.g., natural and synthetic ferrihydrite, goethite, and magnetite).

4. Designing and implementing effective curriculum to strengthen and improve middle school and high school students’ understanding of science and engineering.

Students in the Penn group use many state-of-the-art materials characterization methods, including in situ and ex situ transmission electron microscopy (TEM), in combination with a broad suite of correlative methods, to characterize solid-state changes resulting from reactions with both natural and anthropogenic chemicals. This enables us to quantitatively assess reactivity, reactive surface area, and how reactivity and reactive surface area evolve as reactions proceed and solution conditions change. In addition, materials collected from the field are used in parallel experiments so as to enable meaningful comparisons between the field and the lab.