A smart fluorescent green corrosion inhibitor: Real-time sensing and inhibition performance of carbon dot-modified...

The Development of efficient and eco-friendly corrosion inhibitors for copper is essential for protecting metals in electronic and electrical equipment as well as marine engineering. In this study, a carbon dot-modified chitosan (CS-CDs) corrosion inhibitor was synthesized via pyrolysis and amidation reactions, which enhanced the adsorption performance of chitosan and imparted corrosion-responsive functionality. Electrochemical tests indicated that CS-CDs exhibit excellent corrosion inhibition performance for copper in 3.5 wt% NaCl solution, with an inhibition efficacy of 92.65% at 200 mg/L. Based on DFT and MD simulations, the intrinsic mechanism underlying the enhanced corrosion inhibition performance was revealed at the molecular level. Furthermore, CS-CDs not only possess excellent fluorescence properties but also exhibit a highly sensitive response to Cu²⁺. Once the Cu²⁺ concentration reaches 5 × 10^-4 mol/L or higher, significant fluorescence quenching of the solution is observed, demonstrating its potential for visual monitoring of the corrosion process. This chitosan derivative provides new insight into fluorescent, environmentally friendly corrosion inhibitors and can be used to construct a self-reporting intelligent anti-corrosion field.