Ammonium pyrrolidine dithiocarbamate adsorption on copper surface in neutral chloride media

•PDTC inhibits efficiently copper corrosion in chloride media.•PDTC is mixed corrosion inhibitor of Cu in chloride media.•PDTC forms a chelate complex with cuprous species.•PDTC adsorbs on copper surface during immersion in chloride media.•PDTC hinders the oxide film formation on copper surface. Adsorption of ammonium pyrrolidine dithiocarbamate (PDTC) on copper surface in 0.2 and 30gL−1 NaCl media was investigated by different electrochemical methods and surface analyses. The results from electrochemical measurements showed that PDTC adsorbs rapidly on copper surface and revealed a marked effect of mixed inhibition. Surface analyses confirm the adsorption of PDTC on copper and the formation of a Cu–PDTC complex through the S atoms of PDTC. At high concentrations PDTC prevents oxides and cuprous chloride formation. XPS results showed that PDTC bonds with cuprous species indicating the formation of CuI–PDTC complex.