Tivanski group paper published in special issue
The Tivanski group recently published a paper in the October Journal of Physical Chemistry virtual special issue, “Veronica Vaida Festschrift”.
Despite being of atmospheric importance, direct surface tension measurements of sea spray aerosol (SSA) relevant sub-micrometer particles are very rare. Therefore, we used atomic force microscopy to directly measure the surface tension of individual sub-micrometer SSA particle mimics at ambient temperature and varying relative humidity. Our results show that surface-inactive inorganic and organic compounds at and below 100 Pa s in viscosity show good agreement between the AFM single particle and the bulk solution surface tension measurements at overlapping concentration ranges. Interestingly, surface-active organic compounds show significantly lower values of surface tension relative to the bulk than previously seen anywhere else. This deviation is proposed to originate from surface activity that leads to formation of a closely packed molecular film at the air-liquid interface. Overall, our direct surface tension measurements of various chemical systems, on a single particle basis, can establish relevant constraints on climate models that require surface tension values of SSA, and ultimately contribute toward better understanding the climate and atmospheric impact of aerosols.