Methanol-Tolerant Platinum-Palladium Catalyst Supported on Nitrogen-Doped Carbon Nanofiber for High Concentration Direct Methanol Fuel Cells

Abstract

Pt-Pd catalyst supported on nitrogen-doped carbon nanofiber (N-CNF) was prepared and evaluated as a cathode electrode of the direct methanol fuel cell (DMFC). The N-CNF, which was directly synthesized by the catalytic chemical vapor deposition from acetonitrile at 640 °C, was verified as having a change of electrochemical surface properties such as oxygen reduction reaction (ORR) activities and the electrochemical double layer compared with common carbon black (CB). To attain the competitive oxygen reduction reaction activity with methanol tolerance, the Pt and Pd metals were supported on the CB or the N-CNF. The physical and electrochemical characteristics of the N-CNF–supported Pt-Pd catalyst were examined and compared with catalyst supported on the CB. In addition, DMFC single cells using these catalysts as the cathode electrode were applied to obtain I-V polarization curves and constant current operating performances with high-concentration methanol as the fuel. Pt-Pd catalysts had obvious ORR activity even in the presence of methanol. The higher power density was obtained at all the methanol concentrations when it applied to the membrane electrode assembly (MEA) of the DMFC. When the N-CNF is used as the catalyst support material, a better performance with high-concentration methanol is expected.

The effect of SnO2(110) supports on the geometrical and electronic properties of platinum nanoparticles

“…Currently, Pt-nanoparticles are uniformly dispersed on carbon supports to maximize the active surface area per unit mass of Pt, to stabilize/immobilize the catalyst, to ensure sufficient electronic conductivity, and to decrease cost [6,8,10,[14][15][16][17]. Carbon blacks are the most commonly used supports for Pt and Pt alloys due to their large surface area, good electronic conductivity, and low cost [8,10,16,[18][19][20][21]. Nevertheless, carbon blacks are unstable under the operating conditions experienced at the cathode side of PEFCs, i.e., relatively elevated temperature [3,22], acidic conditions [3,22], humidity [3], and high electrical potential [3,6,22].…”

Water Molecular Adsorption on the Low-Index Pt Surface: A Density Functional Study

“…The said modified Pt-based catalysts described in our literature reviews involve the addition of other metals, e.g. Pt-Ru [7][8], Pt-Co [9], Pt-Cu [10], Pt-Mo [11], Pt-Pd [12], PtRu-Mo [13] -and even Pt-Ru-O-Ir catalyst systems [14]. However, we will not discuss in detail the processes in DMFCs, but we focus on the fundamental part of H2O-Pt systems as one of the reaction steps in MOR, in a scientific perspective.…”

Nitrogen Doped Ordered Mesoporous Carbon as Support of PtRu Nanoparticles for Methanol Electro-Oxidation

“…Thus, the tintroduction of nitrogen on carbon structure seems to decrease the Ru alloyed with Pt, as well as to enrich the Pt amount on the catalyst surface. This behavior could be related with a modification of the electronic structure of the carbon support by the introduction of nitrogen [29,44,45]. Kim et al obtained a different surface metal composition in bimetallic catalysts (PdPt) supported on nitrogen-doped materials in comparison with its nitrogen-free analogue [44].…”

“…This behavior could be related with a modification of the electronic structure of the carbon support by the introduction of nitrogen [29,44,45]. Kim et al obtained a different surface metal composition in bimetallic catalysts (PdPt) supported on nitrogen-doped materials in comparison with its nitrogen-free analogue [44]. The contribution of surface nitrogen on the reduction of Pt and Ru during the synthesis cannot be discarded.…”