J. Mater. Sci. Technol. ›› 2021, Vol. 72: 202-216.DOI: 10.1016/j.jmst.2020.08.064

• Research Article • Previous Articles     Next Articles

Anti-corrosive mechanism of poly (N-ethylaniline)/sodium silicate electrochemical composites for copper: Correlated experimental and in-silico studies

Hao Liua, Baomin Fana,*(), Guifeng Fana, Yucong Maa, Hua Haob, Wen Zhangc   

  1. a College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, China
    b Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
    c College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China
  • Received:2020-06-23 Revised:2020-08-28 Accepted:2020-08-30 Published:2021-05-10 Online:2021-05-10
  • Contact: Baomin Fan
  • About author:* E-mail address: fanbaomin@btbu.edu.cn (B. Fan).


Poly (N-ethylaniline) (PNEA) composites with varying silicate content were fabricated on copper through a novel electropolymerized strategy in acidic solution. Thickness, compactness, conductivity and adhesive strength of the composite (PNEA-10Si) were optimized as silicate content reached 10 mM. Electrochemical, morphological and solution analyses were employed to evaluate the protective performance of PNEA and PNEA-10Si coatings for copper in 3.5 % NaCl solution. Results of electrochemical analyses indicated that as-prepared coatings retarded the oxygen reduction process efficiently for copper in 3.5 % NaCl solution, drained corrosion current density and elevated interfacial charge transfer resistance. Due to favorable barrier effect, compact structure and low porosity index, PNEA-10Si composite exhibited superior anti-corrosive performance, which was more tolerant than PNEA during long-time immersion. PNEA-10Si coated sample exhibited a stable topography after 144 h immersion with the minimum concentration of released ions revealing the improved protection capacity. Electronic/atomic-multiscale calculations were conducted to clarify the deposition and protection mechanism of as-prepared coatings. Outcomes of density functional theory corroborated that silicate is stabilized in the PNEA layer via electrostatic force; and immobile silicate positively contributed to the charge transfer barrier of the composite. Molecular dynamics simulations evidenced that the favorable compatibility between PNEA and silicate facilitated polymer deposition and confined in-situ ions diffusion.

Key words: Electrochemical deposition, Composite coating, Anti-corrosion, Density-functional theory, Molecular dynamic simulation