Authors : Sofia Tahir, Saba Siraj and Muhammad Rizwan
Abstract: In this research work, gold nanoparticles were synthesized by three different methods. These were, seed growth method, citrate-reduction method and gold nanoparticles prepared from sodium borohydride and refluxed with sodium acrylate. These nanoparticles were characterized using UV-visible spectrophotometer, TEM and FESEM. In the seed growth method gold nanoparticles were synthesized by four steps of seeding growth with maximum plasmon bands at 524, 524, 530 and 539 nm as examined by UV-visible spectrophotometer. The TEM micrograph showed that gold nanoparticles obtained from first step of seeding were spherical with 5-10 nm diameters. The second step nanoparticles were spherical and triangular with diameter of about 15-20 nm. Those obtained from third and fourth step of seeding were spherical with17-20 nm and 50-60 nm size, respectively. As the size of gold nanoparticles was increased from 5-60 nm, their SPR band was also increased from 524-539 nm. The citratestabilizedna noparticles were 15-17 nm in size with maximum plasmon band at 521 nm. The UV-visible spectra for the gold nanoparticles synthesized by sodium borohydride in 1,9-NDT showed the appearance of a second red-shifted plasmon resonance band at 950 nm wavelength. The intensity of this band was enhanced with increase in 1,9-NDT concentration.
Sofia Tahir, Saba Siraj and Muhammad Rizwan, 2020. Structural, Morphological and Optical Properties of Metal Nanoparticles Assemblies of Gold. Research Journal of Applied Sciences, 15: 240-248.