Carbon Monoxide Oxidation on Pt Single Crystal Electrodes: Understanding the Catalysis for Low Temperature Fuel Cells

Abstract

Herein the general concepts of fuel cells are discussed, with special attention to low temperature fuel cells working in alkaline media. Alkaline low temperature fuel cells could well be one of the energy sources in the next future. This technology has the potential to provide power to portable devices, transportation and stationary sectors. With the aim to solve the principal catalytic problems at the anode of low temperature fuel cells, a fundamental study of the mechanism and kinetics of carbon monoxide as well as water dissociation on stepped platinum surfaces in alkaline medium is discussed and compared with those in acidic media. Furthermore, cations involved as promoters for catalytic surface reactions are also considered. Therefore, the aim of the present work is not only to provide the new fundamental advances in the electrocatalysis field, but also to understand the reactions occurring at fuel cell catalysts, which may help to improve the fabrication of novel electrodes in order to enhance the performance and to decrease the cost of low temperature fuel cells.

Influence of the metal loading on the electrocatalytic activity of carbon-supported (100) Pt nanoparticles

“…Thus, whereas the 2-3-nm Pt nanoparticles displayed a voltammetric response in 0.5 M H 2 SO 4 similar to that characteristic of an electrochemically activated polyoriented Pt electrode [34,24], that is, a Pt surface without (100) and (111) ordered domains, the current Pt nanoparticles show a preferential (100) surface structure. In this respect, it is well established from Pt single crystals studies with basal plane, stepped and kinked surfaces that the CO stripping reaction is structure-sensitive [53][54][55][56][57][58][59][60][61][62]. In addition, this surface structure sensitivity is also present on the nanoscale as is demonstrated by the use of shape-controlled Pt nanoparticles [6,44,45].…”

Carbon-Supported PtRuMo Electrocatalysts for Direct Alcohol Fuel Cells

“…0.25 V increases with Mo loading and accordingly it is plausible an enhancement of water dissociation at very negative potentials (i.e., lower than 0.25 V). Therefore, an enhanced tolerance towards carbon monoxide is expected [59]. Figure 12 depicts the CO stripping voltammograms recorded at PR, 1MPR and 3MPR catalysts in sulphuric acid solution for two different temperatures (20 and 70 °C).…”

A novel structural design of hybrid nanotube with CNTs and CeO2 supported Pt nanoparticles with improved performance for methanol electro-oxidation

“…Because of the stronger van der Waals interaction between Pt and CeO 2 than Pt and carbon [31], the Pt nanoparticles in Pt/CeO 2 -CNTs-HN catalyst are adsorbed adjacent to CeO 2 . But Pt nanoparticles prefer being inserted into voids formed by CeO 2 rather than deposited on CeO 2 [36], which contributes to the homogeneous distribution of Pt then enhancing the electro-catalytic activity of Pt/CeO 2 -CNTs-HN catalysts. On the other hand, the preference of inserting into voids formed by CeO 2 for Pt nanoparticles makes them have an effective contact with carbon, which can enhance the electron conduction among Pt, CeO 2 and CNTs (from impedance patterns and phase shift plots in Fig.…”