Estimation of the hamaker coefficient for a fuel-cell-supported catalyst system.

Hamaker coefficients are estimated for various nanoparticle-support systems commonly used in polymer electrolyte membrane fuel cells. The interaction energies, cohesion between nanoparticles, and adhesion of nanoparticles on the support are also estimated from the experimental data. Comparison between the bulk properties of platinum metal, calculated from the optical spectra available in the literature, and the nanoparticles are provided. Measurements to obtain the optical properties of the systems of interest are also reported. Implications of the van der Waals forces on the supported catalyst structure properties are discussed. The algorithm used in calculation of the Hamaker coefficient using Lifshitz theory was evaluated with known materials, using the spectral parameters available in the literature, and the results are presented.