Surfactant mediated synthesis and characterization of Boehmite nanowires

Abstract

The Boehmite (AlOOH) nanowires have been prepared by surfactant mediated sol-gel synthetic technique. The resulting nanowires have been characterized by using the XRD and FE-SEM and SEM-EDAX analytical techniques. From the X-ray diffraction (XRD) analysis, it is clearly observed that the nanowire synthesized by sol-gel method has γ-AlOOH crystalline phase. The Fe-SEM analysis shows the formation of wire shaped material having average diameter in the range of 200 nm to 1 micron and length up to several hundred microns. The SEM-EDAX (Element detection X-ray analysis) result suggests the presence of Al & O elements in boehmite nanowires. In order to obtain the mechanism of formation of nanowires, the effect of various reaction parameters such as pH, reactant and surfactant concentration, drying of gel etc. have been studied here. It the observed that the optimum PH ranges for the formation of nanowires is 7 to 9. The anionic surfactant SDS is more suitable surfactant than other anionic surfactants (Na-PSS, DBSA, Na-PAA) and act as a directing agent in the formation of nanowires. Surfactant concentration has no role but the aluminum nitrate concentration plays very important role in the formation of boehmite nanowires. As the aluminum concentration increases the amount of nanowires (%) formation increases. It was also found that drying of gel-cake plays an important role in the conversion Al(OH)3 gel to nanowires