Functionalized surfaces as templates for in situ formation of gold nanopaticle catalyst

COLL 299

Krisanu Bandyopadhyay, krisanu@umd.umich.edu1, Madiha Khalid2, and Natalie Wasio2. (1) Department of Natural Sciences, University of Michigan - Dearborn, 4901 Evergreen Road, Dearborn, MI 48128, (2) Department of Natural Sciences, University of Michigan-Dearborn, 4901 Evergreen Road, Dearborn, MI 48188
Synthesis of gold nanoparticles with size less than 10 nm immobilized on solid support has seen remarkable growth due to their unusual catalytic properties. Although different synthesis strategies, like direct deposition-precipitation or surface-capping methods are explored for achieving a specific size range for these nanostructures; factors controlling size, shape, and interparticle spacing as well as their structure-activity relationship are still poorly understood. Thus, there is a considerable interest for investigating a general preparative route to engineer aggregation-resistant gold nanoparticles for catalytic applications. Functionalized assemblies at the solid/liquid interface are known to act as nano-reactors to generate nanoparticles from the entrapped metal ions. The present work deals with the organized assemblies of polyethylenimine (PEI) silane to generate gold nanoparticles for electro-catalytic oxidation of methanol. The present research also provides the understanding of the effect of reaction conditions to control the structure of resulting Au nanoparticles. X-ray photoelectron spectroscopy (XPS) and Atomic force microscopy (AFM) are used to monitor the chemical and structural development of these nanostructures. This research provides a simple route to prepare a stable and catalytically active surface immobilized metal nanoparticle array with controllable morphology and high monodispersity on different surfaces. Finally, catalytic properties of these nanoparticle arrays will also be demonstrated towards methanol electro-oxidation.