PHOTOACTIVE GOLD NANOPARTICLE SOFTOXOMETALATES (SOM) USING A KEPLERATE FOR SYNTHESIS OF POLYSTYRENE LATEX MICROSPHERES BY PHOTOPOLYMERIZATION

Abstract

In this paper, 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.