Role of Work Function and Potential of Zero Charge on Wetting of Metals

We develop a theory for the maximum (Young’s) contact angle of wetting () for metals based on the electrochemical work function (E‐WF) and interfacial interactions at the droplet surface. In our theory, is the difference of spreading quotient () of metal and retraction quotient () of liquid. The spreading quotient, (<1), is ratio of E‐WF of wet to WF of dry metal and is a measure of spreading tendency and dipolar orientational disorder. The retraction quotient, (<1), is ratio of molecular interfacial interaction energy to the cohesion energy of the liquid, which is a measure of the retraction of drop. The resistance to wetting is governed by the intrinsic electric‐field‐induced dipolar orientational order on the metal, charge reorganization, interlayer dipole–dipole interactions, and surface tension. An increase in E‐WF and a consequent positive shift in PZC also promotes dewetting. The hydrophilic nature of the clean metal surfaces shown as . Theoretical predictions are in agreement with the experimental and MD simulation data.