Study on structure and molecular scale protection mechanism of green Ce,N-CDs anti-bacterial and anti-corrosive inhibitor

Abstract

Using l-histidine and cerium nitrate hexahydrate as raw materials, a green and effective carbon dots (Ce,N-CDs) was prepared using hydrothermal synthesis and their structures were confirmed by professional equipment. The anti-bacterial and anti-corrosive behaviors of Ce,N-CDs were systemically evaluated using plate counting method and electrochemical method, respectively. By analysis, the Ce,N-CDs showed a high bacterial inhibition efficiency for Escherichia coli (E. coli), which was up to 94.27 %. Compared with N-doping carbon dots (N-CDs), the Ce,N-CDs exhibited an excellent anti-corrosive ability. At 200 mg/l, its corrosion inhibition efficiency (IE) for Cu was higher than 90 % at different environment temperatures (308, 318, 323 K), and the corrosion rate (W_L) was sharply reduced. This was attributed to the presence of N–Cu bond and the formation of Ce-containing passive film. The Ce-containing passive film could block the erosion of aggressive ions. The N–Cu bond could facilitated the chemical adsorption on Cu surface, which was confirmed by quantum chemistry (QC) and molecular dynamics (MD).