Study on electrode carbon corrosion of high temperature proton exchange membrane fuel cell

Methodology for Evaluation of Contributions of Ostwald Ripening and Particle Agglomeration to Growth of Catalyst Particles in PEM Fuel Cells

“…At lower voltages, the degradation is much slower, leading to only a small decrease in CO 2 emissions during the 30-minutes test. The validity of this explanation is confirmed by a similar increase in mean particle size during degradation tests, predicted by the degradation model, Δ r mod = 1.40 nm, to the one reported by Bandlamudi [22], Δ r exp = 1.45 nm. These results clearly indicate the importance of coupled degradation modeling, comprising several individual mechanisms from the surface oxidation to the particle growth, in explaining the results of degradation experiments on the HT-PEMFC.…”

“…In the present study we used a recently developed coupled fuel cell operation and catalyst degradation model to analyze the individual contributions of Ostwald ripening and particle agglomeration to the overall growth of particles in the fuel cell catalyst layer during its degradation. The model was calibrated based on the results of two degradation experiments on high temperature polymer electrolyte membrane fuel cell, measuring CO 2 emissions because of the corrosion of the carbon support , and particle size redistribution during a 4,800 h long‐term degradation of a commercial fuel cell . The ability of the model to simultaneously reproduce the results of two distinct experiment using the same parameters confirms the plausibility of the modeling approach used in the study.…”

“…In the experiment by Bandlamudi et al. , the accelerated stress test was performed by feeding the HT‐PEMFC with synthetic air on the cathode and hydrogen on the anode side while keeping it at a constant potential of 0.9, 1.0, 1.1, and 1.2 V using an external potentiostat. The CO 2 emissions were measured for a period of 30 min at each voltage, resulting in the time traces of CO 2 concentrations , shown as dashed line in Figure , with index i denoting each of the four experiments.…”

“…In this paper we study the distinction between both processes, i.e., particle agglomeration and Ostwald ripening, using our recently developed model of fuel cell operation and degradation , . The model is calibrated based on the experimental data on the HT‐PEMFC recently published in , and used to model particle growth during long‐term fuel cell operation. The analysis of particle growth, based on the results of the model, indicates a significant difference in the mean particle size growth when caused by either Ostwald ripening or particle agglomeration.…”

Σύνθεση, Φυσικοχημικός Και Ηλεκτροχημικός Χαρακτηρισμός Ηλεκτροκαταλυτών Για Κυψελίδες Καυσίμου Υψηλής Θερμοκρασίας PEM

“…Σε αυτά τα χαμηλά δυναμικά και στα συνήθη δυναμικά λειτουργίας των κελιών καυσίμου (0.6-0.9 V ως προς το RHE), οι κινητικές των παραπάνω αντιδράσεων είναι σχετικά αργές. Στην πράξη, απαιτούνται δυναμικά μεγαλύτερα των 1.2 V ως προς το RHE, για να διαβρωθεί ο άνθρακα με ικανοποιητική ταχύτητα [167].…”