Graphene based nanomaterials are highly important because of their unique properties such as high contact surface area, high electrical conductivity and their enormous stability. Graphene and related materials have been used as promising catalyst supports in energy conversion and storage applications. In our research, in order to produce more efficient catalyst supports, we successfully modified graphene with various active functional groups such as amine, thiophene, fluorosilane, and RGD peptide by mono and multi-functionalization of graphene oxide. Further, modified polyol process was used to obtain specifically guided growth of Platinum (Pt) nanoparticles on these modified graphene surfaces. Consequently, better dispersion of Pt nanoparticles were obtained with delicate control-ability. As a result, the electrocatalytic activity (ECSA and ORR) was greatly enhanced. These promising nanomaterials can serve as potential candidates for high performance polymer electrolyte membrane fuel cells.
Graphene/polymer Nanocomposites
In this work, superior electrical, mechanical and antibacterial properties of graphene nanosheets were readily incorporated in electrospun poly (vinyl alcohol) (PVA) fibers. The major advantage of this approach is that via co-solvent addition method, a well-dispersed hydrophobic graphene nanosheet distribution in hydrophilic PVA solution was achieved. Thus, improving the final fibers' mechanical and electrical properties. As the final stage of this investigation, effectiveness of this method in preparation of ternary PVA/PANI/rGO fibers and their antibacterial performance was studied. It was shown that effective distribution of conducting components in biodegradable PVA fibers resulted in high antibacterial activity of the final electrospun mats.
Metal-organic frameworks (MOFs) are a new class of porous, highly crystalline materials consisting of metal nodes connected by organic linkers. Due to the simplicity of manipulating or substituting the metal centers and ligands, there are limitless number of possible combinations, which is attractive from a design standpoint. MOFs exhibit many unique properties due to their tunable pore sizes, thermal stability, high volume capacities, large surface areas, and desirable electrochemical characteristics. Our aim is to prepare well dispersed and ordered metal nanoparticles (Ni, Co or Mn) on graphene. For that purpose we have been synthesizing graphene supported MOFs first and then by annealing (to remove organic parts) we will achieve desired catalyst layer. It is also possible to obtain bimetallic nanoparticles starting from two diffent MOFs.