Effects of Surface Treatment and Carboxylic Acid and Anhydride Molecular Dipole Moments on the Volta Potential Values of Zinc Surfaces

This study investigates the Volta potentials of the differently treated zinc surfaces and the interface dipole moments after adsorption of carboxylic acid and anhydride molecules on zinc surfaces by means of scanning Kelvin probe (SKP). The interfacial bonding properties of carbonaceous contamination as well as adsorbed succinic acid, myristic acid, and succinic anhydride molecules with zinc substrates have been investigated using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The variation of the Volta potential due to the treatments applied on zinc was evaluated by means of SKP. Moreover, the dipole moments of adsorbed carboxylic acid and anhydride molecules were measured and correlated to surface hydroxyl fractions and oxide electronic properties. The results clearly showed that the zinc Volta potential varies with the oxide composition, resistance, and the configuration of the molecules adsorbed.