New Ecofriendly Nitrogen-Doped Carbon Quantum Dots as Effective Corrosion Inhibitor for Saturated CO2 3% NaCl Solution

Inspired by the high-water solubility, photoluminescence and low cytotoxicity of N-doped carbon quantum dots (N-CQDs), fluorescent corrosion inhibitors with size of 4–8 nm were synthesized from disodium ethylenediaminetetraacetate, sulfamic acid, and urotropine salt. We expect that these N-CQDs may possess an excellent protective ability to inhibit the corrosion of carbon steel in aggressive solutions owing to its special functional group. The inhibitory mechanism of the inhibitor on N80 steel in saturated CO 2 3 wt % NaCl solution was studied by weight loss, adsorption curve fitting, electrochemical measurement, and surface morphology and elemental analysis. The results show that corrosion of N80 carbon steel in saturated CO 2 3 wt % NaCl solution is significantly inhibited by the addition of N-CQDs, which is attributed to the formation of its adsorption film, preventing the contact of iron with chloride ions and is an effective corrosion inhibitor.