Nitrogen‐doped graphene prepared by low‐temperature thermal treatment as an electrocatalyst support for methanol oxidation

Abstract

In this study, functionalized graphene is used as a carbon-based material to support platinum-ruthenium bimetallic nanoparticles and to improve methanol oxidation reaction activity due to the enhanced physical and electrical properties of graphene. First, surface oxidation is used for creating oxygen functional groups, and then nitrogen doping by thermal treatment with ammonia as the nitrogen precursor. Platinum-ruthenium alloy nanoparticles are dispersed by the impregnation reduction method on the support materials. The final nanocomposite samples contain 8% of oxygen and 3% of nitrogen. Compared to PtRu/GNS and PtRu/CB, the PtRu/NO-GNS catalyst indicates 1.25 and 1.3 times higher surface area, and 2.3 and 4 times higher electrochemical surface area, respectively. The highest methanol oxidation current density of 305 mA/mg and 262 mA/mg is obtained for platinum-ruthenium supported on nitrogen-doped graphene and nitrogen-doped oxidized graphene, which is 2.9 and 2.5 times higher than that for PtRu/GNS, respectively. It is revealed that the nitrogen-doped samples have shown greater activity and long-term stability than other electrocatalysts, including the widely used carbon black supported catalyst.Hence, this work reports the performance of an efficient alternative electrocatalyst with practical application in direct methanol fuel cells.

Carbon black‐heteroatom‐doped graphene aerogel hybrid supported platinum nanoparticles as electrocatalysts for oxidation of methanol and formic acid

“…The larger ECSA indicated good dispersion of metal nanoparticles over the N‐doped graphene support 40 . In addition to, nitrogen‐doped graphene due to the improved electrical conductivity of support and better interaction between metal and support showed the highest ECSA 41 . In a study, the ECSA of the Pt nanoparticles on N‐doped graphene support is approximately 78% higher than that of the Pt nanoparticles on graphene support, which is attributed to the superior dispersion of the Pt nanoparticles on N‐doped support 42 .…”

Electrochemical Performance Improvement of the Catalyst of the Methanol Micro-Fuel Cell Using Carbon Nanotubes

“…e synthesis process is continued for 12 hours at ambient temperature to complete the reduction reaction. Finally, the electrocatalyst has been washed and centrifuged several times and dried at 60°C in a vacuumed oven for 12 hours [2].…”

“…Different clean energy technologies have been evaluated in recent years to replace the current energy systems, which use fossil fuels [1]. Among different power generation technologies with lower greenhouse gas emissions in comparison with the conventional fossil fuel-based systems, fuel cells have some advantages [2]. e fuel cells convert the chemical energy of the fuel directly into heat and power through a set of electrochemical reactions.…”

“…Yu et al [12] used Pt-Ru-NiTiO 3 nanoparticles and found that it has higher catalytic activity than PtRu/C, and the onset potential became 60 mV more negative. Bilondi et al [13] coated PtRu nanoparticles with cerium oxide (CeO 2 ) which increased the oxidation reaction activity of methanol compared to bare PtRu electrocatalyst, and the power density increased 1% per each cm 2 .…”

Low-temperature N-anchored ordered Pt3Co intermetallic nanoparticles as electrocatalysts for methanol oxidation reaction

“…Several recent studies demonstrated that the Pt-M nanoparticles with ordered structures showed promising improvement in the activity and stability of the catalyst. 25,26 For a bimetallic Pt-M alloy system (M = Ru, 27,28 Ni, 29 Cu, 30,31 Pb, 32 Co, 33,34 Sn, 35 etc. ), the addition of M can promote the adsorption and activation decomposition of water at a lower potential and provide adsorbed hydroxyl groups (OH ads ), which serve as oxidants to transform the toxic species (CO ads ) into CO 2 by oxidizing.…”