Edinburgh Napier University

  It is well established that anodes for solid oxide fuel cells (SOFCs) can be manufactured by processes involving final sintering. This research investigated a novel alternative method which relies on the electroless co-deposition of yttria-stabilised zirconia (YSZ) or ceria-stabilised zirconia (CeSZ) and nickel onto a YSZ substrate. This process allows complex or simple shaped substrates to be coated, thereby replacing the high temperature sintering and reduction stages with a single plating operation, which is substantially more cost effective and greatly simplifies the manufacture of any cell design. The technique also eliminates the production of larger nickel grains (which occurs during sintering), thus improving cell performance.

Through a series of multifactoral experiments, a successful method was established and optimised for the deposition of the metal-ceramic composite which was successfully used in Solid Oxide Fuel Cell stack. The typical process involves degreasing and chemical pre-treatment of the substrates, followed by electroless co-deposition of the cermet coating, using either proprietary based chemicals or standard analytical reagents which have been specially formulated.

Through the metallurgical examination of the experimental samples it has been shown that the ratio of the metal to ceramic can be varied, thus catering to a potentially large customer base, and that a composition gradient can be achieved through the coating. Additional parameters such as porosity and electrical conductivity have also been evaluated and the results have been so encouraging that there has been significant commercial interest in the process.

Further work is continuing as part of a Proof of Concept (POC) project, with funding generously provided by Scottish Enterprise. Intellectual Property has been secured initially through funding supplied by Edinburgh Napier University, then subsequently through the POC project, with the aim that on completion of the project a spin-out company from Edinburgh Napier University is established.