PtCo alloy nanoparticles supported on graphene nanosheets with high performance for methanol oxidation

Abstract

PtCo alloy nanoparticles are deposited onto graphene sheets through a facile and reproducible hydrothermal method. During the hydrothermal reaction, the reduction of graphene oxide and PtCo alloy nanoparticles loading can be achieved. X-ray diffraction (XRD) analyses reveal a good crystallinity of the supported Pt nanoparticles in the composites and the formation of PtCo alloy. X-ray photoelectron spectra (XPS) results depict that Pt mainly exists in the metallic form, while much of the cobalt is oxidized. Transmission electron microscope (TEM) observations show that the PtCo alloy nanoparticles are uniformly dispersed on graphene nanosheets compared with multiwalled carbon nanotubes (MWNTs). This PtCo-graphene composite exhibits excellent electrocatalytic activity and high poison tolerance toward poisoning species for methanol oxidation reaction, far outperforming the Pt-graphene or PtCo-MWNTs composites with the same feeding ratio of Pt/carbon. graphene, PtCo alloy nanoparticles, electrocatalyst, methanol oxidation, fuel cells Citation:Huang H J, Sun D P, Wang X. PtCo alloy nanoparticles supported on graphene nanosheets with high performance for methanol oxidation.

Methanol oxidation reaction activity of microwave-irradiated and heat-treated Pt/Co and Pt/Ni nano-electrocatalysts

“…Broadening of all peaks after the addition of the Co or Ni is to be noted (Table S1, calculated using the Scherrer equation) suggesting a reduction in the Pt particle size on synthesis of the new materials. The observed broadening could also be due to the amorphous nature of the catalysts [5,8]. The peak positions for the HT samples showed little change in the (111) peak after the addition of Co (40.15 ) or Ni (40.01 ) suggesting little alloying has occurred using this synthesis procedure.…”

“…However, the use of Pt has drawbacks that include the high cost of Pt [5], as well as the propensity for Pt to be poisoned by carbon monoxide (CO), which is one of the carbonaceous species formed during the methanol dissociation process [6,7]. A general remedy to this problem is to alloy Pt with cheaper transition metals such as nickel [8], cobalt [5], iron [9] and ruthenium [10]. In addition to lowering the overall costs, these metals also increase the CO tolerance of the Pt catalysts.…”

“…The effect of the addition that the alloying metals such as Co [2,5] and Ni [8,14] have on the electrocatalytic activity of Pt is well researched. Paulus et al [21] studied the catalytic activity of Pt 3 Ni and Pt 3 Co bulk alloy catalysts with emphasis on the alloy surface properties.…”

Synthesis and Electrochemical Evaluation of Carbon Supported Pt-Co Bimetallic Catalysts Prepared by Electroless Deposition and Modified Charge Enhanced Dry Impregnation

“…The electrochemical surface area (ECSA) was calculated in Equation (2) by measuring the charge density associated with the adsorption of hydrogen (qPt, in μC/m 2 -electrode) between 0.05 and 0.40 V [48], the charge required to reduce a monolayer of protons on Pt (Γ) which is 210 μC/cm 2 Pt, and the Pt content or loading on the electrode (L), in gPt/m 2 -electrode [49].…”

Probing the Catalytic Activity of Tin-Platinum Decorated Graphene; Liquid Phase Oxidation of Cyclohexane

“…Since reported for the first time in 2004, graphene has gained great attention in the scientific community [12]. Graphene, a two-dimensional material exhibits highly desirable physical characteristics such as a theoretical surface area of 2630 m 2 /g [13], high electronic and thermal conductivities [14], excellent mechanical properties [15], remarkable optical and electrical properties [16], and excellent chemical stability [17].…”