Amino Acids-Assisted Synthesis Of Nanomaterials And Their Novel Properties

In this paper, hydrothermal and solvothermal synthesis were employed to prepare Fe-Co Layered Double Hydroxide(Fe-Co LDH), Cobalt Ferrite (CoFe2O4) and Ceria(CeO2) nano-materials. At the presence of amino acid, by changing the reaction parameters including types and concentrations of reactants and solvents, reaction time and heating temperature, monodispersed nano-structure materials with various morphologies were synthesized. To determine the phase, morphology and property of these nano-materials, the as-prepared samples were characterized by XRD, FT-IR, FESEM, TEM, VSM, TGA and UV-vis. Main research results were as follows:ethylene glycol and deionized water were used as solvents, amino acid as modifier, solvothermal and hydrothermal synthesis were successfully introduced respectively to prepare monodispersed CoⅡ5.84Ⅲ2.16(OH)16(CO3)1.08·0.32H2O (JCPDS 50-0235) with flowerlike and octahedral structure, CoFe2O4 (JCPDS 22-1086) particles with diameters of 15nm and 100nm, CeO2 (JCPDS 34-0394) with sphere, cube and rod like structure. Numerous comparative experiments indicated that the concentration of amino acid and sodium hydroxide, reaction time and heating temperature are the key factors which have big effects on the morphology of samples in the solvothermal and hydrothermal synthesis. The adsorption performances of Fe-Co LDH and CoFe2O4 with different morphologies were measured through UV-Vis spectra. The results showed that the as-prepared samples exhibited a remarkable adsorption efficiency on anionic dyes such as Methyl orange, Congo red and Acid blue 80, but rarely adsorbed the cationic dyes, for example, Methylene blue and Cationic red X-GTL. A unsurprising phenomenon was observed that flowerlike samples had a better adsorption performance than the octahedral ones. These results suggest that the samples prefer adsorbing anionic dyes and the morphology also have effect on the adsorption performance to some extent.