A thermostatic cell with gas diffusion electrode for oxygen reduction reaction under fuel cell relevant conditions

Chen, Yan‐Xia; Li, Ming Fang; Xu, Jie; Ye, Shen

doi:10.1016/j.elecom.2009.05.023

Cited by 25 publications

(25 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…7,30,44 At 0.9 V vs. RHE, the anodic scan has a current density of 0.282 mA cm -2 Spec , corresponding to a value of 0.25 A mg -1…”

Section: Oxygen Reduction Reactionmentioning

confidence: 99%

“…Each platinum nano-particle within the electrode should have optimal proton access, gas access and an electronic path to study intrinsic electrocatalytic properties of the catalyst. 30 These three criteria should be maintained throughout the working conditions (e.g., temperature, humidity and potential). If a reaction site is starved for any of the three, its activity will be reduced, which skews the average activity and introduces an error.…”

Section: Introductionmentioning

confidence: 99%

“…This catalyst layer was 40 μm thick, with a loading of 200 μg Pt cm -2 ; not optimized for intrinsic catalyst property studies. Later, Chen et al 30 sputtered a 3 nm layer of platinum (roughness factor of 1.45) onto the surface of a substrate 60 to achieve an ultra thin catalyst layer for temperature dependence studies.The next logical step is to develop a method for depositing catalyst layers using Pt/C, which is the standard for PEFC electrodes, and geared towards studying intrinsic activity. Figure 65 Error!…”

mentioning

confidence: 99%

“…Cyclic voltammetry showed the PCTE membrane to be a suitable material to be used in PEFC/acidic conditions. For the 30 ORR, a maximum current density of 185 mA cm -2 Spec or 800 mA cm -2Geo was achieved at 0.38 V vs. RHE for an electrode with a platinum loading of 4.9 μg Pt cm -2 . At 0.9 V vs. RHE, where a typical measurement in the RDE is made, the current density was 0.282 mA cm -2 Spec .…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 4 more Smart Citations

Electrocatalytic performance of fuel cell reactions at low catalyst loading and high mass transport

Zalitis

Kramer

Kucernak

2013

Phys. Chem. Chem. Phys.

180

194

View full text Add to dashboard Cite

An alternative approach to the rotating disk electrode (RDE) for characterising fuel cell electrocatalysts is presented. The approach combines high mass transport with a flat, uniform, and homogeneous catalyst deposition process, well suited for studying intrinsic catalyst properties at realistic operating conditions of a polymer electrolyte fuel cell (PEFC). Uniform catalyst layers were produced with loadings as low as 0.16 μg Pt cm -2 and thicknesses as low as 200 nm. Such ultra thin catalyst layers are considered 10 advantageous to minimize internal resistances and mass transport limitations. Geometric current densities as high as 5.7 A cm -2 Geo were experimentally achieved at a loading of 10.15 μgPt cm -2 for the hydrogen oxidation reaction (HOR) at room temperature, which is three orders of magnitude higher than current densities achievable with the RDE. Modelling of the associated diffusion field suggests that such high performance is enabled by fast lateral diffusion within the electrode. The electrodes operate over a wide 15 potential range with insignificant mass transport losses, allowing the study of the ORR at high overpotentials. Electrodes produced a specific current density of 31 ± 9 mA cm -2Spec at a potential of 0.65 V vs. RHE for the oxygen reduction reaction (ORR) and 600 ± 60 mA cm -2 Spec for the peak potential of the HOR. The mass activities of Pt/C catalysts towards the ORR was found to exceed a range of literature PEFC mass activities across the entire potential range. The HOR also revealed fine structure in 20 the limiting current range and an asymptotic current decay for potentials above 0.36 V. These characteristics are not visible with techniques limited by mass transport in aqueous media such as the RDE. IntroductionUnderstanding the kinetics of the oxygen reduction reaction 25 (ORR) and hydrogen oxidation reaction (HOR) on platinum nano-particles is vital for polymer electrolyte fuel cell (PEFC) development. Each platinum nano-particle within the electrode should have optimal proton access, gas access and an electronic path to study intrinsic electrocatalytic properties of the catalyst. 30 These three criteria should be maintained throughout the working conditions (e.g., temperature, humidity and potential). If a reaction site is starved for any of the three, its activity will be reduced, which skews the average activity and introduces an error. It is paramount to minimize the number of underperforming 35 catalyst sites to determine intrinsic catalyst properties. Ideally, the catalyst layer should be made as thin as possible. Thus, all the catalyst particles will be close to the perfluorosulfonic acid (PFSA) membrane for ionic access and close to the gas diffusion layer (GDL) for gas access and an electronic path, removing 40 internal limitations. Mass transport limitations lead to concentration polarization across thick electrodes, 1-3 limiting the active thickness to about 5 μm at high current densities, regardless of how thick the catalyst layer is. 1 The majority of ORR and ...

show abstract

“…7,30,44 At 0.9 V vs. RHE, the anodic scan has a current density of 0.282 mA cm -2 Spec , corresponding to a value of 0.25 A mg -1…”

Section: Oxygen Reduction Reactionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%