Effect of Sn on the micro-structure, composition and anti-corrosion performance of reduced glutathione film on copper

Abstract

An organic-inorganic hybrid film was successfully constructed via reduced glutathione (GSH) and SnSO4 on copper surface. The adsorption of sulfhydryl groups (-SH) on copper was the prerequisite for the synergistic effect of GSH and SnSO4. The addition of Sn (II) into the film formation system could improve the corrosion protection efficiency of GSH film from 90.52% to 99.89%. SEM results demonstrated that the synergistic effect between GSH and Sn (II) can improve the connection of the film and substrate. The XPS results indicated that Sn elements participated in the formation of the film with Sn (II), Sn (IV) and Sn (0). The excellent corrosion resistance of the film was attributed to the close connection between the film and the substrate and the doping of Sn with three valence states.