Catalyst-Exsolving Anode-Supported Low-Temperature Solid Oxide Fuel Cell

Abstract

While ceramic anodes provide a path to overcome the obstacles of the current state of the art cermet-based solid oxide fuel cells (SOFCs), they are limited by processing challenges, low conductivity, poor catalytic activity, and instability. Here, we address these challenges by fabricating a ceramic-anode-supported SOFC composed of Sr2Fe0.4Ni0.8Mo0.8O6−δ (SFNM) which is highly conductive and spontaneously exsolves nano-catalysts for low temperature operation (600 °C). Using a simple and scalable procedure, we manufacture these SOFCs to have 60% lower ohmic loss than their electrolyte-supported analogues and we take advantage of the in-situ catalyst exsolution to circumvent additional catalyst deposition steps. We show that the catalyst exsolution triples the peak power density up to ∼200 mW cm−2 at 600 °C with H2 fuel, which is comparable to other ceramic anode SOFCs operating at considerably higher temperatures (>700 °C). Further, we discuss two major challenges facing exsolution-anode supported SOFCs, show our efforts to identify and address the root causes of such problems, and describe a potential path forward for next-generation anodes.