Layered Double Hydroxide Ordered Ultrathin Films And Electrochemical Performance

Hydrotalcites, including hydrotalcite and hydrotalcites, also called layered double hydroxides(LDH), is made up by layer which includes divalent/trivalent metals and interlayer anions. Supramolecular LDHs materials could be generated by supramolecular intercalation. In more than a hundred years since LDH was discovered, it has been used in various fields such as catalysis, adsorption, ion exchange agent, electrochemical, photochemical, et al. because of its favourable compatibility. Recently, a wider range of application such as environmental protection, cosmetic, polymer materials, nano composite materials, medicine, bio- inorganic material has been developed. The synthesis, peeling, self- assembly, electrode modification were studied. And charge transport mechanism electrode modified with Mg/Fe/[Fe(CN)6]/GCE were illuminated for the further research.In this paper, Mg/Fe-NO3 hydrotalcite was prepared from Mg/Fe-CO3 hydrotalcite with the employment of acid and alkali method, and the samples were characterized by XRD, FT-IR, SEM and EDS. Mg/Fe-NO3 hydrotalcite was delaminated through reflux method In formamide solution. Water-yellow transparent colloidal solution was prepared which was Mg/Fe hydrotalcite nano sheet.The colloidal solution showed Tyndall phenomenon and kept stable for a week based on experimental results.The effect of Mg/Fe mole ratio, temperature, delamination time, initial hydrotalcite amount were studied. The delamination process was studied from the perspective of thermodynamics and kinetics to provides theoretical basis for delamination reaction. The Mg/Fe/[Fe(CN)6] film materials was prepared by layer by layer method, and the structures of samples were analysed through XRD, FT-IR, EDS. The results showed that Mg/Fe/[Fe(CN)6] film had the same structure to LDHs.The glassy carbon electrode was modified with Mg/Fe/[Fe(CN)6] assembled onto its surface through LBL. The electrode electrochemical reaction parameters were optimized: assembled for 10 layers, concentration of electrolyte K3[Fe(CN)6](0.5 mol/L), electrolytic system p H(9.0), scanning rate(100 mV/s), and the measuring stability and storage stability was studied. The electrochemical behavior of Mg/Fe/[Fe(CN)6]/GCE was studied by cyclic voltammetry and electrochemical impedance spectroscopy to illuminate the transfer process of charge. The electrical resistance and capacitance was calculated through equivalent circuit diagram simulation.