CeO2/rGO/Pt sandwich nanostructure: rGO-enhanced electron transmission between metal oxide and metal nanoparticles for anodic methanol oxidation of direct methanol fuel cells.
ABSTRACT Pt-based nanocomposites have been of great research interest. In this paper, we design an efficient MO/rGO/Pt sandwich nanostructure as an anodic electrocatalyst for DMFCs with combination of the merits of rigid structure of metallic oxides (MOs) and excellent electronic conductivity of reduced oxidized graphene (rGO) as well as overcoming their shortcomings. In this case, the CeO(2)/rGO/Pt sandwich nanostructure is successfully fabricated through a facile hydrothermal approach in the presence of graphene oxide and CeO(2) nanoparticles. This structure has a unique building architecture where rGO wraps up the CeO(2) nanoparticles and Pt nanoparticles are homogeneously dispersed on the surface of rGO. This novel structure endows this material with great electrocatalytic performance in methanol oxidation: it reduces the overpotential of methanol oxidation significantly and its electrocatalytic activity and stability are much enhanced compared with Pt/rGO, CeO(2)/Pt and Pt/C catalysts. This work supplies a unique MO/rGO/Pt sandwich nanostructure as an efficient way to improve the electrocatalytic performance, which will surely shed some light on the exploration of some novel structures of electrocatalyst for DMFCs.
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ABSTRACT: Carbon dioxide (CO 2) is one of the main gases produced by human activity and is responsible for the green house effect. Numerous routes for CO 2 capture and reduction are currently under investigation. Another ap-proach to mitigate the CO 2 content in the atmosphere is to convert it into useful species such as hydrocarbon mole-cules that can be used for fuel. In this view, copper is one of the most interesting catalyst materials for CO 2 reduction due to its remarkable ability to generate hydrocarbon fuels. However, its utilization as an effective catalyst for CO 2 reduction is hampered by its oxidation and relatively high voltages. We have fabricated hybrid materials for CO 2 reduction by combining the activity of copper and the conductivity of reduced graphene oxide (rGO). Cu nanoparticles (CuNPs) deposited on rGO have demon-strated higher current density and lower overpotential compared to other copper-based electrodes that we have tested. The CuNPs on rGO also exhibit better stability, preserving their catalytic activity without degradation for several hours.Materials for Renewable and Sustainable Energy. 02/2015; 4(1).
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ABSTRACT: Silicon carbide and porous carbon hybrids (SiC-PC) were directly synthesized via a facile evaporation-induced-assembly approach combined with the in-situ carbothermal reduction, in which the soluble formaldehyde resin (RF), poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer (PEO-PPO-PEO) (F127) and tetraethoxysilane (TEOS) were employed as carbon sources, porogents and silicon sources, respectively. The synthetic SiC-PC hybrid exhibited a large specific surface area of 1163 m2 g-1, and the SiC nanoparticles (NPs) with about 10 nm are well dispersed on the carbon materials. After loading Pt NPs, the resulting Pt/Si-PC catalyst exhibits the highest unit mass electroactivity (836.93 A g–1 Pt) towards methanol electrooxidation, which is about 3.05 and 3.61 times those of the commercial PtRu/C and Pt/C catalysts. Moreover, the Pt/SiC-PC catalyst displays the best stability compared with the the commercial PtRu/C and Pt/C catalysts. The obtained enhanced electrocatalytic activity is attributed not only to the mutual effect of the hybrid support and the metal nanoparticles, but also to its large surface area for high utilization efficiency of Pt and desirable mass transportation in a porous electrode. These results indicate that SiC-PC hybrid has great potential as a high-performance catalyst support for fuel cell electrocatalyst.RSC Advances 09/2014; · 3.71 Impact Factor
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ABSTRACT: Sandwich-like Pt/Mn3O4/RGO is fabricated by a spontaneous and electroless approach.•Small Pt nanoparticles were uniformly deposited on the Mn3O4/RGO surface.•Pt/Mn3O4/RGO shows great stability and catalytic activity to methanol electroxidation.Electrochimica Acta 12/2014; 149. · 4.09 Impact Factor