Utilization of the graphene aerogel as PEM fuel cell catalyst support: Effect of polypyrrole (PPy) and polydimethylsiloxane (PDMS) addition

• Published in: International journal of hydrogen energy Vol. 45; no. 60; pp. 34818 - 34836
• Main Authors: Öner, Emine, Öztürk, Ayşenur, Yurtcan, Ayşe Bayrakçeken
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 09.12.2020
• Subjects: Catalyst support; Graphene aerogel; PEM fuel cell; Polydimethylsiloxane; Polypyrrole; Graphene aerogel; Polydimethylsiloxane; Polypyrrole; Catalyst support; PEM fuel cell
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2020.05.053

In this study, three-dimensional (3D) graphene aerogel (GA) was synthesized by a self-assembly hydrothermal process as a PEM fuel cell catalyst support. The synthesized GA was also modified with the polypyrrole (PPy) by in-situ chemical oxidative polymerization of the pyrrole monomer (PPy-GA). The electrocatalytic performance of the platinum (Pt) nanoparticles (NPs) supported with both GA and PPy-GA materials towards oxygen reduction reaction (ORR) was investigated. In addition, the hydrophobic polydimethylsiloxane (PDMS) polymer was added to the catalyst ink media in order to enhance the hydrophobic property and durability of the synthesized GA and PPy-GA supported Pt catalysts. Pt NPs were decorated over the support materials with the microwave irradiation technique. Various characterization techniques such as FTIR, Raman Spectroscopy, BET, SEM, EDX, TEM, TGA, contact angle measurements, 3D topography images and four-point probe electrical conductivity measurements were performed in order to analyze the GA based support materials. Electrochemical characterizations were also carried out with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. It was observed that PDMS addition to the catalyst ink media increased the electrocatalytic activity and durability of the GA supported Pt catalyst. Otherwise, the performance of the PPy modified GA supported Pt catalyst was negatively affected by the addition of PDMS to the catalyst media. [Display omitted] •Hydrothermally synthesized GA and PPy modified GA were used as catalyst supports.•Pt/GA and Pt/PPy-GA catalysts were prepared by microwave irradiation.•PDMS polymer was also added to the catalyst inks for more hydrophobicity.•Pt/GA & PDMS and Pt/PPy-GA & PDMS have more durability towards carbon corrosion.•Pt/GA & PDMS catalyst exhibited the best electrocatalytic activity for ORR.