Multidimension Insight Involving Experimental and in Silico Investigation into the Corrosion Inhibition of N,N-Dibenzyl Dithiocarbamate Acid on Copper in Sulfuric Acid Solution

Seeking the efficient and green corrosion inhibitor for copper in certain conditions is an imminent problem. In this account, the performance and mechanism of corrosion inhibition for N,N-dibenzyl dithiocarbamate acid (DBDC) on copper in 0.5 M H2SO4 solution are investigated with a multidimension approach combining experimental and theoretical methods. The results demonstrate that the DBDC molecule can firmly adhere to the copper surface to form a hydrophobic film, which obeys Langmuir adsorption isotherm. The self-assembled monolayer (SAM) presents a wonderful anticorrosion efficiency of DBDC reaching to 99.7% within a short self-assembly time at 298.15 K, according to electrochemical measurements. In addition, the atomic force microscope (AFM) and the scanning electron microscopy (SEM) reveal that the copper slab becomes smoother in the presence of DBDC, which has a positive effect on the anticorrosion properties of copper specimens. Quantum chemical calculations (such as density functional theory (DFT) method) and molecular dynamics (MD) simulation techniques subsequently interpret the experimental findings. Furthermore, the toxicity of DBDC is evaluated through quantitative structure-activity relationship (QSAR) measurements, and it is lowest comparing with other five reference corrosion inhibitors. All of the evidence shows that DBDC is a highly efficient and environmentally friendly anticorrosion product for copper in H2SO4 solution. Significantly, researches on corrosion inhibition of DBDC in this work could provide the extrapolation or guideline for further studies including its complexes and homologues.