Synthesis and Electrochemical Evaluation of MSNs-PbAE Nanocontainers for the Controlled Release of Caffeine as a Corrosion Inhibitor
Martín Aguirre-Pulido,
Jorge A. González-Sánchez,
Luis R. Dzib-Pérez,
Montserrat Soria-Castro,
Alejandro Ávila-Ortega,
William A. Talavera-Pech
Affiliations
Martín Aguirre-Pulido
Corrosion Research Center, Autonomous University of Campeche, Avenida Héroe de Nacozari 480, Campeche 24079, Mexico
Jorge A. González-Sánchez
Corrosion Research Center, Autonomous University of Campeche, Avenida Héroe de Nacozari 480, Campeche 24079, Mexico
Luis R. Dzib-Pérez
Corrosion Research Center, Autonomous University of Campeche, Avenida Héroe de Nacozari 480, Campeche 24079, Mexico
Montserrat Soria-Castro
Department of Applied Physics, CINVESTAV-IPN Merida Unit, Km 6 Old Road to Progreso, Mérida 97310, Mexico
Alejandro Ávila-Ortega
Faculty of Chemical Engineering, Autonomous University of Yucatán (UADY), Periférico Norte Km 33.5, 13615, Chuburna de Hidalgo Inn, Mérida 97203, Mexico
William A. Talavera-Pech
Corrosion Research Center, Autonomous University of Campeche, Avenida Héroe de Nacozari 480, Campeche 24079, Mexico
In this paper, a controlled-release system of caffeine as a corrosion inhibitor was obtained by encapsulating it in MCM-41 silica nanoparticles coated with a poly(β-amino ester) (PbAE), a pH-sensible polymer. Encapsulation was verified using Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TGA). The release of caffeine from the nanocontainers was analyzed in electrolytes with pH values of 4, 5, and 7 using UV–Vis, showing a 21% higher release in acidic electrolytes than in neutral electrolytes, corroborating its pH sensitivity. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used to determine the inhibition mode and efficiency of the encapsulated and free caffeine. The caffeine released from the nanocontainers showed the highest efficiency, which was 85.19%. These results indicate that these nanocontainers could have potential use in smart anticorrosion coating applications.
