Scalable Aqueous-Based Synthesis of Graphene and Platinum Nanoparticle Aerogels for Electrocatalysis in Fuel Cells

Duncan R. Day, Uta A. Givens, Ryan N. Morrall, F. John Burpo, Caspar C. Yi, Enoch A. Nagelli*

Department of Chemistry and Life Science, United States Military Academy

West Point, New York 10996

ABSTRACT

Graphene/noble metal nanoparticle aerogels are promising conductive and ultra-high surface area three-dimensional (3D) electrodes that utilize the high capacitance of graphene in combination with the catalytic properties of noble metals for high performance energy storage devices. Their porous structure and conformability with other structural materials make them viable electrode candidates to be integrated into fuel cells and batteries. We report the successful development of a graphene-based aerogel formed first by the electrostatic assembly of platinum magnus salts with graphene oxide sheets. The subsequent chemical reduction of this assembled material results in a highly porous nanostructure that can enable electron transport between the graphene sheets and catalytic platinum. The aerogel is produced in a rapid and entirely aqueous process without addition of heat or cross-linking agents between the graphene sheets and platinum salts. After chemical reduction, the aqueous graphene-platinum solution is then critically dried to result in a monolithic solid structure that demonstrates high surface area within its porous structure. Scanning Electron Microscopy (SEM) is used to verify the integration of graphene sheets with platinum nanoparticles and nanotubes into an inter-connected 3D aerogel. The structural features of the aerogel was confirmed with Raman Spectroscopy with the presence of signature of D-band, G-band, and 2D-band peaks. Electrochemical impedance spectroscopy (EIS) was used to determine the specific capacitance of 442 mF/cm² and an areal specific resistance (ASR) of 0.41Ω cm². The high capacity and low electronic and ionic resistance of the graphene-platinum aerogel indicate the potential as catalytic electrodes in fuel cells.

KEYWORDS: Graphene, Platinum Nanoparticles, Fuel Cell, Electrocatalysis

CONTACT: Dr. Enoch Nagelli, Dept of Chemistry and Life Science, United States Military Academy, West Point, New York 10996. Email: enoch.nagelli@westpoint.edu TEL: 845-938-3904.