Lee, Kug-Seung Yoo, Sung Jong Ahn, Docheon Kim, Soo-Kil Hwang, Seung Jun Sung, Yung-Eun Kim, Hyung-Juhn Cho, EunAe Henkensmeier, Dirk Lim, Tae-Hoon Jang, Jong Hyun 2024-01-20T16:03:56Z 2024-01-20T16:03:56Z 2021-09-05 2011-10-01 0013-4686 https://pubs.kist.re.kr/handle/201004/129906 The phosphate adsorption characteristics and its effect on oxygen reduction reaction (ORR) were examined for various carbon-supported catalysts (Pt/C, Pt3Co/C, PtCo/C, and Au-core-Pt-shell/C). Using cyclic voltammetry (CV) and the addition of phosphoric acid, the degree of phosphate adsorption for each catalyst was evaluated based on the intensity of the phosphate adsorption peaks (0.25-0.3 V and 0.5-0.65 V) and on the decrease in the platinum oxidation current (0.9V). In the N2O reduction technique, the surface structures were analyzed using N2O as an electrochemical probe, which showed that as the Co content increased, (i) steps or defects were introduced by surface reconstruction, (ii) the phosphate adsorbed more strongly compared to Pt/C with a preference for the terrace sites, and (iii) the potential of zero total charge (PZTC) shifted to negative potentials. In the case of the Au-core-Pt-shell/C, the phosphate adsorption was found to be weaker than other catalysts, including Pt/C catalyst. The relative ORR activity with PA addition, normalized by that with no phosphate adsorption, was significantly smaller for Co containing alloy catalysts (PtCo/C: 18.2%) and larger for Au-core-Pt-shell (30.2%) compared with the Pt/C catalyst (27.8%), confirming the phosphate adsorption characteristics of each catalyst, as measured by CV and N2O reduction analysis. (C) 2011 Elsevier Ltd. All rights reserved. English PERGAMON-ELSEVIER SCIENCE LTD PHOSPHORIC-ACID CONCENTRATION ZERO TOTAL CHARGE FUEL-CELL POLYMER ELECTROLYTE ANION ADSORPTION PLATINUM SURFACES KINETICS PT(111) NANOPARTICLES MEMBRANE Phosphate adsorption and its effect on oxygen reduction reaction for PtxCoy alloy and Au-core-Pt-shell electrocatalysts Article 10.1016/j.electacta.2011.07.084 1 ELECTROCHIMICA ACTA, v.56, no.24, pp.8802 - 8810 ELECTROCHIMICA ACTA 56 24 8802 8810 scie scopus 000295601600097 2-s2.0-80052800720 Electrochemistry Electrochemistry Article PHOSPHORIC-ACID CONCENTRATION ZERO TOTAL CHARGE FUEL-CELL POLYMER ELECTROLYTE ANION ADSORPTION PLATINUM SURFACES KINETICS PT(111) NANOPARTICLES MEMBRANE Phosphate adsorption Phosphoric acid Oxygen reduction reaction Potential of zero total charge High-temperature PEMFC