Characterization of Platinum Nanoparticles Deposited on Functionalized Graphene Sheets

Abstract

Due to its special electronic and ballistic transport properties, graphene has attracted much interest from researchers. In this study, platinum (Pt) nanoparticles were deposited on oxidized graphene sheets (cG). The graphene sheets were applied to overcome the corrosion problems of carbon black at operating conditions of proton exchange membrane fuel cells. To enhance the interfacial interactions between the graphene sheets and the Pt nanoparticles, the oxygen-containing functional groups were introduced onto the surface of graphene sheets. The results showed the Pt nanoparticles were uniformly dispersed on the surface of graphene sheets with a mean Pt particle size of 2.08 nm. The Pt nanoparticles deposited on graphene sheets exhibited better crystallinity and higher oxygen resistance. The metal Pt was the predominant Pt chemical state on Pt/cG (60.4%). The results from the cyclic voltammetry analysis showed the value of the electrochemical surface area (ECSA) was 88 m2/g (Pt/cG), much higher than that of Pt/C (46 m2/g). The long-term test illustrated the degradation in ECSA exhibited the order of Pt/C (33%) > Pt/cG (7%). The values of the utilization efficiency were calculated to be 64% for Pt/cG and 32% for Pt/C.

A Sequential Process of Graphene Exfoliation and Site-Selective Copper/Graphene Metallization Enabled by Multifunctional 1-Pyrenebutyric Acid Tetrabutylammonium Salt

“…The spectrum is resolved as: C (sp 2 ) at 284.8 eV, C (sp 3 ) at 285.5 eV, CO at 287.6 eV, O−CO at 288.8 eV, and π−π* at 290.5 eV. 63,64 One can see that the C (sp 2 ) from graphene dominates the spectrum, whereas the existence of C (sp 3 ), CO, and O−CO groups is primarily attributed to PyB-TBA in the film. The presence of PyB-TBA is further confirmed by the Fourier transform infrared (FT-IR) result (Figure S3).…”

Electrochemical and Microstructural Investigations of PtFe Nanocompounds Synthesized by Atmospheric-Pressure Plasma Jet

“…The composition of the PtFe nanocompound layer was and 724.5 eV) and Fe(III) (711.2 eV and 726.5 eV). [27][28][29] The satellite peaks are ∼8 eV above the Fe2p main peak and is located at 717 eV and 719 eV. The peak at 714.6 eV corresponds to Fe(II) with surface ligands.…”

“…They can be further deconvoluted into metallic state Pt 0 (71.0 eV and 74.35 eV) and two oxidized states Pt(II) (72.4 eV and 75.75 eV) and Pt(IV) (73.6 eV and 77.3 eV). 29,33 Table II shows the areal ratio for each Pt component. In contrast to Fe, which is present in the oxidized state after APPJ processing, most Pt is reduced to metallic form after APPJ processing.…”

Bionanotechnology: Silver Nanoparticles Supported on Bovine Bone Powder Used as Bactericide

“…An important strategy to limit the size, protect, and recover the synthesized nanoparticles, is the support adequate selection. In this sense, various supports have been assessed: (a) of biological origin like core/shell [18,19], cotton [20,21], wood [3], or natural fibers [22], and (b) man-made such as titania [23], various polymers [24][25][26][27], graphene sheets [28], or ceramics [29]. Regarding bovine bone powder, it has been shown to exhibit a good mechanical, thermal, and chemical resistance (it does not oxidize) and also shows great affinity to metallic nanoparticles because of hydroxy (OH − ) and phosphate (PO 4 3− ) groups, which exhibit a rather high ability to anchor the nanoparticles to the support.…”