The ability of a surface to completely absorb a liquid droplet is an important property that can be controlled by geometrical structure and chemical composition of the surface. Here, using Laplace pressure and Gibbs free energy (GFE) considerations, a capped truncated microcone array geometry is proposed to obtain a near zero degree for contact angle (θ) of a water droplet. Our results showed that two essential conditions must be met to achieve a superabsorbent surface.
View Article and Find Full Text PDFElectrospinning is a simple and cheap process for forming one-dimensional (1D) nanofibers with controllable size, morphology, and chemistry. Besides these, the ultrahigh surface area with industrialization capability has attracted extensive interest in the research community. On the other hand, a photocatalytic process is a promising method for degrading organic pollutants that cannot be removed by conventional wastewater treatment.
View Article and Find Full Text PDFThe wetting property of spherical particles in a hexagonal close-packed (HCP) ordering from extended Gibbs free energy (GFE) and Laplace pressure view points is studied. A formalism is proposed to predict the contact angle (θ) of a droplet on the HCP films and penetration angle (α) of the liquid on the spherical particles. Then, the extended Laplace pressure for the layered HCP ordering is calculated and a correlation between the wetting angle, sign of pressure, and pressure gradient is achieved.
View Article and Find Full Text PDF