Electrohydrodynamic-Jet Deposition of Pt-Based Fuel Cell Catalysts

Fuel cell electrodes are traditionally fabricated by hand-painting or spraying a catalyst ink onto a gas diffusion electrode or membrane. However, electrodes prepared via these techniques do not always have a uniform distribution of catalyst. Recently, electrohydrodynamic-jet (e-jet) printing has been developed as a method to deposit a variety of chemical and biological materials with excellent precision for various applications in electronics, biotechnology, and microelectro-mechanical systems. Here we demonstrate e-jet deposition of Pt-based fuel cell catalysts as a technique for achieving uniform catalyst distribution on microelectrodes. E-jet deposition is studied as a function of applied potential, and at 450 V, printed catalyst lines are very uniform at ∼10 μm in width. For electrode areas less than 1 mm², deposition times are on the order of a few hours, which compares well with traditional hand-painting deposition times. Uniform catalyst distribution is important to reducing catalyst loading, and the deposition technique presented here shows significant possibility to produce electrodes with high uniformity.