Wetting properties of glycerol on silicon, native SiO₂, and bulk SiO₂by scanning polarization force microscopy

AbstractScanning polarization force microscopy, a relatively new non-contact scanning probe microscopy technique, was applied in order to investigate the properties of liquid surfaces (droplets), such as: topography, microscopic contact angle θ, surface potential energy P(e), spreading coefficient S, and disjoining pressure П. Investigations were carried out on glycerol droplets deposited on surfaces of bare silicon, silicon covered with native oxide, and bulk silicon oxide. Contact angle values were determined from directly measured topography profiles of micro- and nanodroplets. Values of surface potential energy, spreading coefficient, and disjoining pressure were calculated based on a model of the dependence of contact angle on droplet height. The results of these experiments offer valuable insights into the mechanisms of wetting phenomena at the microscopic scale.Keywords: scanning polarization force microscopymicro- and nanodropletswettingcontact anglesurface potential energydisjoining pressure FundingThis work was supported by the Romanian Ministry of National Education and by the European Union through the European Regional Development Fund, under project [POSCCE-O212-2009-2/12689/717]; and by the Romanian Ministry of National Education under projects [ERA-NET4-001/07.04.2011] and [IFA-CEAC2-08/01.03.2012]. The authors also acknowledge the financial support of the European Union and the Romanian Government, received through [grant number POSDRU/107/1.5/S/76813].