Catalytic one-step synthesis of Pt-decorated few-layer graphenes

Abstract

This study presents the influence of the various reaction parameters (catalyst concentration, reaction temperature, hydrocarbon flow rate, and reaction time) on the one-step growth of few-layer graphenes decorated with metallic platinum (Pt) nanoparticles. The latter were synthesized over a Pt/MgO catalyst using radio-frequency catalytic chemical vapor deposition (CCVD) from methane. A mixture of nanotubes and graphenes in various ratios was produced depending on the synthesis conditions. The nanotubes have a few walls (generally 2 or 3, but the maximum number observed was 7) with diameters in the range of a few to several nanometers (D max ext z 7 nm). The graphene structures have a few square-shaped layers with dimensions ranging between 80 and 100 nm, which are decorated with Pt nanoparticles (with 70% having diameters between 4 and 8 nm) both on the flat surfaces as well as on the edges. Our experimental findings demonstrate that it is relatively easy to obtain predominantly graphenes using the Pt/MgO (2 wt% Pt) catalyst system at 1000 C, with a 100 mL min À1 hydrocarbon flow rate and a reaction time of 30 minutes.

Graphene based nanomaterials as chemical sensors for hydrogen peroxide – A comparison study of their intrinsic peroxidase catalytic behavior

“…The FT-IR and XPS data presented in our previous works [9][10][11] showed that cCVD graphene are clean carbon honeycomb surfaces, while the chemically obtained nanocomposites posses some residual functional groups that can be involved in the sensing mechanism. A special case is represented by the N-Gr (Figs.…”

“…The synthesis and TEM characterization of few-layer graphene with various metallic nanoparticles (Gr-Au, Gr-Ag, Gr-Pt,) was previously reported (Scheme 2) [9][10][11].…”

“…Graphene-metalic nanoparticles composites (Gr-Au, Gr-Ag and Gr-Pt) were prepared by catalytic Chemical Vapor Deposition with Induction Heating (cCVD-IH) as described in detail elsewhere [9][10][11]. Briefly, Gr-Au, Gr-Ag and Gr-Pt composites were prepared over the corresponding mixed catalyst (Au x /MgO, Ag x /MgO, Pt x /MgO, where x = 3 wt%) at 1000 • C, using methane gas as carbon source.…”

“…The methods corresponding to the first approach (e.g. catalytic chemical vapor deposition [9][10][11]) are generally providing high-quality graphene with quite low productivity. Similar quality of graphene nanosheets but limited quantities can be obtained by mechanical exfoliation of graphite as a top-down approach.…”

New nanocomposite-graphene pastes based stochastic microsensors

“…14,15 Briey, the two samples were prepared by catalytic Chemical Vapor Deposition with Induction Heating (cCVD-IH) using the corresponding mixed catalyst (Au x /MgO and Pt x /MgO, where…”