Synthesis of silver nanostructures of varying morphologies through seed mediated growth approach Sadhan Samanta, Santanu Pyne, Priyanka Sarkar, Gobinda P. Sahoo, Harekrishna Bar, Dipak Kr. Bhui, Ajay Misra ⁎ Department of Chemistry and Chemical Technology, Vidyasagar University, Midnapore 721 102, West Bengal, India abstract article info Article history: Received 12 September 2009 Received in revised form 15 February 2010 Accepted 18 February 2010 Available online 24 February 2010 Keywords: Silver nanostructure Surface plasmon resonance (SPR) Sodium dodecyl sulphate (SDS) We report a method to synthesize silver nanoparticles of varying morphologies by a seeding growth approach at room temperature. Seeds are prepared by reducing silver nitrate with sodium borohydride, and trisodium citrate is used as capping agent. This citrate capped seed sol is added to the growth solution containing ascorbic acid, sodium dodecyl sulphate (SDS) and sodium hydroxide. Colour of the growth solution changes from colourless to pink and the surface plasmon resonance (SPR) shows two distinct bands, indicating the formation of anisotropically grown silver nanostructures. Synthesized silver nanoparticles are characterized by UV–vis spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. Silver nanoseeds are spherical in shape with diameter ranges from 8 to 16 nm. On the other hand, a mixture of morphologies with shapes like triangular and hexagonal nanoplates, nanorods are obtained in the growth solution. XRD results suggest that the particles are crystalline in nature with face centered cubic (fcc) geometry. © 2010 Elsevier B.V. All rights reserved. 1. Introduction The area of nanoparticle research has witnessed tremendous growth due to the unusual chemical and physical properties dem- onstrated by this intermediate state of matter. Due to their small size, these crystallite exhibits novel material properties that are largely different from their bulk counterpart [1]. Nanoscale materials are attracting much interest in recent time for their possible use in areas like optoelectronics [2–4], catalysis [5,6], information storage [7], biosensors [8], plasmonics [9,10], optical sensing [11,12], surface enhanced Raman scattering (SERS) [13–15] and very recently surface enhanced fluorescence [16,17] . Among the noble metal nanoparticles silver is perhaps the most widely studied because of its possible applications in areas such as photonics [18–20], microelectronics [1,21], photo catalysis [22–24] and lithography [25,26]. Again silver nanoparticles show a very strong surface plasmon resonance (SPR) band in the visible region of light with an extinction coefficient up to four times than that of gold nanoparticles [27]. The efficiency of the interaction of nanosized silver particles with light is attributed to the large density of conducting electrons and the unique frequency dependence of the real and imaginary parts of the dielectric function [28]. To utilize and optimize the chemical and physical properties of nanosized metal particles, a large spectrum of research has been focused to control the size and shape, which is crucial in tuning their physical, chemical and optical properties. Various methods, including physical and chemical means, such as chemical reduction [29–31], electrochemical reduction [32], photochemical reduction[33], green synthesis [34,35], heat evaporation [36], laser ablation [37], chemical vapor deposition [38], thermal decomposition in organic solvents [39], and molecular beam epitaxy [40] are being used for the synthesis of metal nanoparticles. For physical methods high temperature, vacuum and expensive equipments are required but chemical methods are convenient, simple and inexpensive. Silver nanoparticles with differ- ent shapes have been synthesized. These include zero dimensional spherical or tetrahedral quantum dots [41], one dimensional silver nanorods and wires [42] and two dimensional nanoplates [43], nanoprisms [44] and nanodisks [45]. Among these particles two dimensional nanoparticles are attractive due to their significant ability to control optical properties. In this paper, we are going to report a new solution phase seed mediated growth approach for the synthesis of silver nanoparticles of various morphologies. Since the shape of seed particles plays a vital role in controlling the morphology of nanoparticles during the growth process, we have decided to use sodium dodecyl sulphate (SDS) as soft template to obtain different twined structured particles. As synthe- sized silver sol obtained through seed mediated growth process is pink in colour and shows two sharp intense SPR band; the red one (537 nm) Journal of Molecular Liquids 153 (2010) 170–173 ⁎ Corresponding author. Fax: +91 3222 275329. E-mail address: ajaymsr@yahoo.co.in (A. Misra). 0167-7322/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.molliq.2010.02.008 Contents lists available at ScienceDirect Journal of Molecular Liquids journal homepage: www.elsevier.com/locate/molliq