Structure of Pt(111)/Ionomer Membrane Interface and Its Bias-Induced Change in Membrane Electrode Assembly

• Published in: Journal of physical chemistry. C Vol. 117; no. 23; pp. 12168 - 12171
• Main Authors: Masuda, Takuya, Fukumitsu, Hitoshi, Kondo, Toshihiro, Naohara, Hideo, Tamura, Kazuhisa, Sakata, Osami, Uosaki, Kohei
• Format: Journal Article
• Language: English
• Published: Columbus, OH American Chemical Society 13.06.2013
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Mechanical and acoustical properties; Physical properties of thin films, nonelectronic; Physics; Structure of solids and liquids; crystallography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); X-ray diffraction and scattering; X-ray scattering (including small-angle scattering); Polymer electrolytes; Oxide layer; Surface scattering; Mechanical properties; X ray scattering; Adhesion; Interface; Single crystal; Fuel cell; Tribology
• DOI: 10.1021/jp402251z
• ISSN: 1932-7447

The structure of the perfluorosulfonated ionomer (PFSI)/Pt(111) interface in a membrane electrode assembly (MEA)-like configuration of a polymer electrolyte membrane (PEM) fuel cell, that is, a vacuum evaporated Pt layer/PEM(Nafion membrane)/PFSI(adhesion Nafion layer)/Pt(111) single crystal, and its bias-induced change were investigated by surface X-ray scattering measurement at an atomic level. Crystal truncation rod measurement shows that PFSI adsorbed on the Pt(111)-(1 × 1) surface without bias. When the Pt(111) electrode was positively biased to form Pt oxide, the PFSI layer was detached from the Pt surface and oxygen atoms penetrated into the Pt lattice.