Study of Silica and Silver Microparticles Synthesis and Microfluidic Devices
Authors:Miguel Meza, Ernesto Mojica, Erik Willett
Mentor:Steven Chuang, Director, FirstEnergy Advanced Energy Research Center Professor of Polymer Science, The University of Akron
The synthesis of different types of microparticles including silver nanowires and silica microspheres was evaluated by traditional synthesis methods. The use of a microfluidic device is proposed for producing uniform particles, and for the rapid characterization of the products under multiple reaction conditions. Silica microparticles can be prepared by hydrolysis and condensation of precursors like alkylsilanes and sodium silicate. Hydrolysis reactions promote nucleation under acid or base catalyzed conditions, and the condensation reaction promotes the silica network formation. The ratio of the hydrolysis and condensation reaction rates governs the morphology of the particles. The size, shape, and polydispersity of these particles are also sensitive to the presence of co-solvents like PEG or low molecular weight alcohols, and to the pH of the reaction media. In this work we present a summary of reaction conditions for preparing various morphologies of silica microparticles and silver nanowires, and proposed a simple method for fabricating PMMA microfluidic devices that can generate stable reaction environments. The reaction products were characterized by scanning electron microscopy (SEM). The evaluation of microparticles synthesis using microfluidics devices could provide valuable information for determining the proper reaction conditions in the development of novel materials.  Li, X.; Wang, L.; Yan, G. Cryst. Res. Technol. 2011, 46, 427.  Li, Y.; Cheng, S.; Dai, P.; Liang, X.; Ke, Y. Chemical Communications 2009, 0, 1085.