Ph.D. Candidate

Mailing Address:
4044 Derring Hall
Blacksburg, Virginia 24061 USA

Office: 227 ICTAS
Office Phone: 540.231.8585
Fax: 540.231.3386
rafrench@vt.edu

Research interests: I study the environmental impact of both engineered and naturally-occurring nanomaterials. My research focuses on the interface of these materials with the natural environment. I investigate their surface reactivity through changes in adsorption capacity, aggregation, and microtopography. I am also interested in the role that microbes play in these changes.

Brief research description: My dissertation research will investigate the surface reactivity and fundamental properties of the nanomineral schwertmannite. Schwertmannite is an iron oxyhydroxide sulfate mineral often formed in acid mine drainage sites (AMD). It forms ~ 1µm spheres covered in spikes that range from 100-300 nm in length and only 10 nm in diameter (Figure 1). Schwertmannite is metastable with respect to goethite, but as it is constantly being formed under AMD conditions it will likely play an important role in heavy metal cycling in these environments. We have successfully synthesized schwertmannite to yield a variety of surface morphologies. We will use these synthetic minerals to investigate the role of schwertmannite’s unique nanostructured surface in arsenic cycling. Analytical techniques used in this investigation include powder x-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy on our world class FEI Titan.