Polymer network of graphene oxide with covalently attached 2-(4′-Hydroxyphenyl)fulleropyrrolidine and Palladium: Synthesis, properties and theoretical studies

Abstract

A new single layer graphene oxide hybrid polymeric material was fabricated in which the fullerene moieties covalently attached to the edges of surface of SLGO sheets were coordinated to palladium atom in an η2-fasion, SLGO-php-C60/Pd. The polymer was characterized by SEM, TEM, FT-IR and Raman techniques. The newly formed material exhibited reversible electrochemical activity in the negative potential range due to the reduction of fullerene cages with an overall electrochemical behavior resembling that of typical organic conducting polymers. The electron density of states calculated using DFT method clearly confirmed the fullerene cage reduction via electron transfer from the low-lying SLGO states. Therefore, coordination polymers of fullerene moieties bonded to the graphene sheets are easier to reduce in comparison to the coordination polymers of pristine C60. In addition, the spectroscopic and electrochemical properties of SLGO-php-C60/Pd hybrid polymeric material were also compared with php-C60/Pd polymer and SLGO-php-C60 hybrid films to seek film morphology-property relations. The present study extends the application of graphene oxide providing electrically conducting, redox-active polymer material for different applications.