Anisotropic wetting of ZnO by Bi2O3 with and without nanometer-thick surficial amorphous films

摘要: Abstract Anisotropic formation of equilibrium-thickness Bi2O3-enriched surficial amorphous films (SAFs) on ZnO has been documented [Luo J, Chiang Y-M. Acta Mater 2000;48:4501]. This study further explores anisotropic wetting single crystals by Bi2O3-rich liquid with and without SAFs. For Bi2O3 the { 1 2 ¯ 0 } surfaces wherein nanometer-thick SAFs are present in equilibrium partial drops, measured (advancing) contact angle decreases increasing temperature, but it stabilizes at ∼6° above ∼860 °C. In contrast, is virtually a constant where not present. observation suggests that presence nanoscale follows generalized Cahn model. Faceted ridge triple lines associated pinning effects observed. Observation analysis unique two-stage isothermal drop receding kinetics show complete does occur up to 1050 °C estimated be ∼4° via two methods. Quantitative evaluation thermodynamic model shows observed “residual” ∼4–6° extended SAF stability can explained basis significant attractive London dispersion force.