Electroless synthesis of multibranched gold nanostructures encapsulated by poly( o-phenylenediamine) in Nafion

Abstract

Multibranched gold (Au) nanocomposite materials encapsulated by poly( o-phenylenediamine) (P oPD) (Au@P oPD) were synthesized in a Nafion polymer film through the electroless synthetic route. The micro-heterogeneous structured Nafion film acted as a reaction vessel and as the template for the formation of Au@P oPD nanocomposite materials leading to the formation of highly uniform distribution of high density of the polymer–gold nanocomposite material. The formation of Au@P oPD nanomaterials at the GP/Nf surface was scrutinized by recording in situ absorption spectra and was characterized. The formation of the (1 1 1) plane of gold was dominant at the Au@P oPD nanocomposite. The ratio of the benzenoid and quinoid units of the P oPD (ca. 1.65) observed for the Au@P oPD confirmed that the micro-heterogeneous structure of Nf film acted as a reaction vessel and as template for the formation of Au@P oPD nanocomposite material. Both P oPD and Au at the Au@P oPD nanocomposite showed electrochemical activities at the GC/Nf–Au@P oPD modified electrode. The electrocatalytic activity of the GC/Nf–Au@PoPD modified electrode was studied for oxygen reduction reaction (ORR).