Infrared Spectra of 1-5 micron Dust Particles in Plasmonic Mesh

Some types of dust, such as powdered quartz and coal dust, can enter the lungs and cause serious health problems. It is known that an increase in concentration of particulate matter will correlate to an increase in death rate. These particles and particulate matter in general, are under EPA regulation. Particles less than ~5 μm can be inhaled into the human lungs and can cause diseases, while larger particles are filtered by the human nose and throat. The characterization of the size and chemical composition of respirable dust will be important in future health studies. It is difficult to obtain good infrared spectra of particles that are the same size as the wavelength of light. Spectra of such particles are dominated by scattering rather than absorption. This affects the ability to identify the chemical composition of the particles. This project solves the scattering problem by capturing single dust particles in the holes of infrared plasmonic mesh. “Scatter-free” infrared spectra were recorded to determine the chemical composition of respirable dust particles in the 1-5 µm critical size region.No embarg