Dataset for: A Cross-Laboratory Comparison Study of Titan Haze Analogs: Surface Energy

In Titan's nitrogen-methane atmosphere, photochemistry leads to the
production of complex organic particles, forming Titan’s thick haze
layers. Laboratory-produced aerosol analogs, or "tholins", are
produced in a number of laboratories; however, most previous studies have
investigated analogs produced by only one laboratory rather than a
systematic, comparative analysis. In this study, we performed a
comparative study of an important material property, the surface energy,
of seven tholin samples produced in three independent laboratories under a
broad range of experimental conditions, and explored their commonalities
and differences. All seven tholin samples are found to have high surface
energies, and are therefore highly cohesive. Thus, if the surface
sediments on Titan are similar to tholins, future missions such as
Dragonfly will likely encounter sticky sediments. We also identified a
commonality between all the tholin samples: a high dispersive (non-polar)
surface energy component of at least 30 mJ/m2. This common property could
be shared by the actual haze particles on Titan as well. Given that the
most abundant species interacting with the haze on Titan (methane, ethane,
and nitrogen) are non-polar in nature, the dispersive surface energy
component of the haze particles could be a determinant factor in
condensate-haze and haze-lake liquids interactions on Titan. With this
common trait of tholin samples, we confirmed the findings of a previous
study by Yu et al. (2020) that haze particles are likely good cloud
condensation nuclei (CCN) for methane and ethane clouds and would likely
be completely wetted by the hydrocarbon lakes on Titan.