Hal Van Ryswyk Research

John Stauffer Professor
PhD, University of Wisconsin-Madison


My interests run from analytical and environmental chemistry to solid-state materials science. Current research in the Van Ryswyk group centers around three major thrusts:

Thin Film Photovoltaics

We create dye-sensitized solar cells utilizing nanostructured zinc oxide photoanodes made from nanoparticles, nanorods, and nanotubes. The goal is to create low-cost photovoltaics that can be produced easily for large-area applications. We also create solid-state bulk heterojunction solar cells from inks made from colloidal lead sulfide quantum dots. We explore the fundamental limitations of delivering a monolayer of quantum dots to uniformly and conformally cover surfaces textured on the nanometer length scale. We are interested in the chemistry of ligand exchange and the materials science and physics of droplet drying on surfaces in the context of printing or spraying high-efficiency solid-state solar cells on large-area substrates.

Lead Levels in Soil from Vehicle Emissions

Lead in soil from vehicle emissions is a leading cause of childhood lead poisoning in southern California. Wedeveloped a service-learning module for the general chemistry course at HMC wherein our first-year students work with local fifth- and sixth-grade students to determine lead levels in soil throughout our community. We utilized statistical sampling methods, GPS mapping, microwave-assisted digestion, and atomic absorption analysis in a preliminary study of soil at the Bernard Field Station adjacent to old U.S. Route 66 in Claremont. We have worked with Vista del Valle, Oakmont, Mountain View, and Sumner elementary schools in the Claremont Unified School District to map the lead content of their playgrounds.

Experiments for Instructional Laboratories

We have published a range of experiments for instructional general chemistry, instrumental methods, and nanoscale materials chemistry laboratories. Examples include a synthetic and structural determination experiment in the general chemistry laboratory utilizing bench-top NMR, diffuse reflectance Fourier transform infrared spectroscopy, and atmospheric pressure chemical ionization mass spectrometry, a pulsed field gradient NMR experiment to measure the diameter of quantum dots in the instrumental methods laboratory, and a photoelectrochemical experiment using easy-to-synthesize semiconductors to split water in the materials chemistry laboratory.