Pendant bubble method for an accurate characterization of superhydrophobic surfaces.
The commonly used sessile drop method for measuring contact angles and surface tension suffers from errors on superhydrophobic surfaces. This occurs from unavoidable experimental error in determining the vertical location of the liquid-solid-vapor interface due to a camera's finite pixel resolution, thereby necessitating the development and application of subpixel algorithms. We demonstrate here the advantage of a pendant bubble in decreasing the resulting error prior to the application of additional algorithms. For sessile drops to attain an equivalent accuracy, the pixel count would have to be increased by 2 orders of magnitude.
Laboratory for Optics, Acoustics, and Mechanics, Department of Mechanical & Aerospace Engineering, Monash University - Clayton Campus, VIC 3800, Australia. william.yl.ling@gmail.com
William Yeong Liang
WY
Ling
Tuck Wah
TW
Ng
Adrian
A
Neild