Monodispersed Pt alloy nanoparticles for fuel cell: from discovery to scale up

R. Wang, K. Pupek, T. Dzwiniel, H. Lv, N. Becknell, P. Papa Lopes, P.F.B. Dias Martins, N. Markovic, V. Stamenkovic
Argonne National Laboratory,
United States

Keywords: scale up, Fuel cell, Oxygen reduction reaction, PtNi nanoparticles, Membrane electrode assembly, Flow reactor

Summary:

In the last few decades, noble metal alloy nanomaterials with monodispersed particle size, controlled composition, shape, and morphology have been developed using colloidal synthesis methods. These well-controlled nanomaterials usually show improved performance over commercial catalysts for different applications such as oxygen reduction reaction. To bring these well-controlled nanomaterials from the discovery lab to real world applications, device level measurements are required. One critical step is the scale up the synthesis procedure from milligram per batch level to gram scale and above. In this talk, I will present our effort on the scale up of a well-controlled Pt alloy nanoparticle catalyst. I will discuss the successful scale up of a monodispersed PtNi nanoparticle catalyst from milligram to 5 g per batch by one-pot synthesis and precisely controlled nanoparticle loading and leaching procedures. The electrochemical activity and durability measured on rotating disk electrode coupled with in-situ ICP will be discussed. The DOE 2020 target performance was exceeded in 50 cm2 membrane electrode assembly demonstrating the high quality of the scaled up samples. To further scale up the synthesis of these monodispersed alloy catalyst beyond gram scale, we transferred the synthesis of monodispersed PtNi nanoparticle from batch synthesis to continuous flow reactor. The challenges and benefits of flow reactor regarding alloy nanoparticle synthesis will be presented. The possibility of integrating flow reactor synthesis and nanoparticle loading procedure will also be discussed aiming to develop a platform for expedited fuel cell catalyst development and manufacturing.