The Grassian group is involved in several research areas including surface chemistry of environmental interfaces, heterogeneous atmospheric chemistry, climate impact of atmospheric aerosols, and environmental and health aspects of nanoscience and nanotechnology.

ATR-FTIR spectroscopy with liquid cell

ATR-FTIR spectroscopy with liquid cell

In these studies, a commercial ATR horizontal liquid cell apparatus (Pike Technology) was modified for these experiments.

Deposited thin film of nanoparticles

The Attenuated Total Reflection (ATR)-FTIR liquid flow cell is used to measure the infrared spectrum of molecules adsorbed on metal and metal oxide nanoparticles from solution. Recent experiments done in the Grassian group to investigate the uptake of environmentally and biologically relevant molecules on nanoparticle surfaces recently demonstrated the utility of this approach.

A sample of nanoparticles (e.g. TiO, CuO, ZnO, and CeO2) is evenly dispersed on the ATR crystal element. The solution containing the compounds of interest is pumped over the thin film made on the surface with the use of liquid flow cell. The spectra are collected using a Themo-Nicolete FTIR spectrometer equipped with a MCT/A detector. This technique provides molecular level information on difference between solution phase and adsorbed phase molecules, different modes of adsorption and quantitative adsorption with careful calibration.