The dominant role of adsorbed fluid layers on the polar surfaces of ZnO in ambientatmospheric conditions

Abstract

Polar ZnO surfaces with O- and Zn-termination were studied with atomic and lateral force microscopy and force curves. Adsorbed fluid layers on both surfaces are found to dominate their adhesion properties in air. The hydrophilic O-surface has a substantially thicker adsorbed layer and larger residual particle densities. Our data suggest that different preparation is required for the two surfaces before use in epitaxy, and may resolve some contradictions in the literature. The data also indicate that adsorbed fluid layers may be important in the growth of certain ZnO nanostructures.