Doxepin as corrosion inhibitor for copper in 3.5 wt. % NaCl solution

Abstract

The effect of 3-(dibenzo[b,e]oxepin-11(6H)-ylidene)-N,Ndimethylpropane- 1-amine (doxepin) on the corrosion behaviour of copper in 3.5 wt.% NaCl solution was investigated by electrochemical techniques, SEM-EDX and quantum chemical calculations. Polarization curves indicate that doxepin acts as a mixed-type inhibitor. Impedance data also prove the anticorrosive proprieties of doxepin, due to its adsorption on the copper surface. The inhibition efficiency of doxepin increases with increasing its concentration, reaching a maximum value of 88.8% at 5 mM. SEM-EDX analysis revealed that doxepin is able to prevent the formation of the oxides on the copper surface. Quantum chemical calculations are in agreement with the results obtained by electrochemical measurements.