18 Mercaptan/ethanol System Self-assembly Membrane for Prevention of Silver Discoloration

18 mercaptan (ODT) is an environmental friendly metal treatment agent. Self-assembled monolayers of ODT/ethanol system adsorbed on the surface of silver were propared and the prevention against discoloration behavior of silver surface was investigated by means of accelerated discoloration experiment, polarization curve, EIS and circular voltammetric methods. The results showed that in the same experimental conditions (the concentration of 18 mercaptan was 0.05 mol/dm3 and the temperature was 50 ℃), the best self-assemlly time was 1 h, the self-assembled monolayers were compact and well prevented discoloration behavior of silver surface.