Development of gold tiny particles and particles in different sizes at varying precursor concentration

Mubarak Ali and I-Nan Lin

Abstract

Coalescence (or growth) of tiny particles to larger particles has been an exciting and practical research topic in nanotechnology. This study deals with development of gold particles at varying precursor concentration in a custom-built setup. Under the tuned ratio of bipolar pulse OFF to ON time, tiny particles of different sizes and shapes develop depending on the amount of gold precursor. When compact monolayer assembly is formed on solution surface, nano energy in packet shapes binds gold atoms in own shape. Between 0.07 mM and 0.90 mM precursor concentration, tiny particles develop in both triangular and non-triangular shapes. Tiny particles of triangular shape develop in a large number at precursor concentrations 0.30 mM and 0.60 mM. Hence, nanoparticles and particles also developed in different geometrical shapes. Such tiny particles pack due to the exerted force in immersing format, where made structures of smooth elements assemble to develop nanoparticles and particles of different shapes. Tiny particles of non-geometrical shapes do not assemble at a common point and their assembling develops a nanoparticle or particle of distorted or spherical shape. This occurs mainly when precursor concentrations are 0.05 mM and 1.20 mM. At 50 sccm argon flow rate, nanoparticles and particles develop in the same shapes as in case of 100 sccm. For different precursor concentrations, different colours of solutions indicate different features of nanoparticles and particles. This study clarifies the necessary concentration of precursor to develop colloids of different sizes.