Synthesis and characterization of Pt/modified MWNT as electrocatalyst for applications in high temperature PEMFC's

• Main Author: Ορφανίδη, Αλίν
• Other Authors: Μπεμπέλης, Συμεών
• Format: Thesis
• Language: English
• Published: 2012
• Subjects: Carbon nanotubes; Electrocatalysts; ORR; Polyol synthesis; Νανοσωλήνες άνθρακα; Ηλεκτροκαταλύτες; 660.299 5

A new approach towards the development of electrocatalytic layers for use in high temperature polymer electrolyte membrane fuel cells is reported. Modified carbon nanotubes were used as the support. The aim was to achieve a uniform distribution of polar groups, which can interact with phosphoric acid, on the surface of the modified carbon support. Multi-wall carbon nanotubes were selected due to their unique properties regarding electronic conductivity and specific surface area. They were surface modified introducing pyridine based groups on the side walls which are known to interact with phosphoric acid. The different supports were thoroughly characterized by means of relevant techniques such as RAMAN,XPS and TGA. Platinum was deposited on the new carbon supports resulting in the newly synthesized catalysts,which were also thoroughly characterized by means of XRD,EDX,TEM and H2 Chemisorption. Stable and finely distributed Pt catalysts with nanoparticles size ranging between 2 and 4 nm were obtained using the chemically modified nanotubes as supports. Measurements of the catalytic activity towards oxygen reduction were also performed in order to evaluate the potential use of these materials as catalytic layers in PEMFCs.