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arXiv · 1402.6495

Photoactive Gold Nanoparticle Soft-oxometalates (SOM) using a Keplerate for Synthesis of Polystyrene Latex Microspheres by Photo-polymerization

Atharva Sahasrabudhe·Soumyajit Roy
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Abstract

A green and facile synthetic protocol for the preparation of photoactive gold nanoparticle-soft oxometalates (AuNP-SOM) using a unique Keplarate type oxomolybdate cluster viz. {Mo$_{132}$}, is reported. The as synthesized AuNP-SOMs are fully characterized by Electronic absorption spectroscopy, Raman spectroscopy and High resolution transmission electron microscopy (HR-TEM). We further demonstrate that by merely tuning the ratio of the precursors in solution it is possible to control the morphology of AuNP-SOM nanostructures. Moreover, these photoactive AuNP-SOMs are employed as photocatalysts for the photopolymerization of styrene to generate colloidal monodisperse polystyrene microspheres in a controllable way in the absence of any external co-initiator or inert atmosphere. Effect of styrene concentration on the size of microspheres is studied using DLS and optical microscopy. Finally, the role of AuNP-SOMs as efficient photocatalyst is established through several control experiments and a reaction pathway is proposed.

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Atharva Sahasrabudhe, Soumyajit Roy. 2014-02-26. Photoactive Gold Nanoparticle Soft-oxometalates (SOM) using a Keplerate for Synthesis of Polystyrene Latex Microspheres by Photo-polymerization. https://doi.org/10.1142/s2251237314400024

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