New Materials, Structures and Concepts for Solid Oxide Cells

The key technical challenges that fuel cell developers need to address in advancing this technology areperformance, durability and cost. Allthree need to be achieved in parallel; however, there is often competitivetensions... [ view full abstract ]

The key technical challenges that fuel cell developers need to address in advancing this technology areperformance, durability and cost. Allthree need to be achieved in parallel; however, there is often competitivetensions meaning that e.g. performance is achieved at the expense ofdurability. The greatest challenge facing Solid oxide cells (SOC), in both fueland electrolysis cell modes (i.e SOFCs and SOECs) is to deliver high,long-lasting electrocatalytic activity while ensuring cost and time-efficient electrodemanufacture.  Ultimately, this can best be achieved by growing appropriatenanoarchitectures under operationally relevant conditions, rather than throughintricate ex situ procedures.  Here wepresent the growth of a finely dispersed array of anchored metal nanoparticleson an oxide electrode, yielding a sevenfold increase in fuel cell maximum powerdensity.  These new electrode structuresare capable of delivering high performances in both fuel cell and electrolysismode (e.g. 2 Wcm^-2 in humidified H₂ and 2.75 Acm^-2 at 1.3 V in 50% H₂O/N₂, at 900°C). Both thenanostructures and corresponding electrochemical activity show no degradationover 150 hours of testing. These results not only prove that in operandotreatments can yield emergent nanomaterials, which in turn deliver exceptionalperformance, but also provide proof of concept that electrolysis and fuel cellscan be unified in a single, high performance, versatile and easilymanufacturable device. This opens exciting new possibilities for simple,quasi-instantaneous production of highly active nanostructures forreinvigorating SOC cells during operation.