Temperature-Regulated Surface Properties of Membranes Based on Concentrated Silver Sol Stabilized by AOT in n-Decane

The surface properties of silver membranes (metal content as high as 97 wt %) have been comprehensively analyzed. The membranes have been obtained via the self-assembly from an electrophoretic nanoparticle concentrate (~1.7 M) followed by sintering at 250–500°C. Increasing the sintering temperature makes it possible to modify the surface properties of the resulting membranes. The root-mean-square roughnesses of the front and back sides increase (from 47 to 104 nm and from 119 to 152 nm, respectively), while the porosities decrease (from 52.7 to 28.4% and from 46.1 to 19.9%, respectively). Due to the silver base and the developed porous structure, the samples are characterized by a low mechanical stiffness (~481 kPa) and can be further modified by force lithography. Regardless of the sintering temperature, the membranes exhibit asymmetric wettability. The water contact angle difference between the two sides is as large as 52°. : membrane, organosol, silver nanoparticle, porosity, wettability