Anode fabrication for solid oxide fuel cells: Electroless and electrodeposition of nickel and silver into doped ceria scaffolds

• Published in: International Journal of Hydrogen Energy
• Main Author: Jamil Z.; Ruiz-Trejo E.; Boldrin P.; Brandon N.P.
• Format: Article
• Language: English
• Published: Elsevier Ltd 2016
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84992305093&doi=10.1016%2fj.ijhydene.2016.04.061&partnerID=40&md5=a152fd9941b17610d6d7d6dd5991bf79

A novel fabrication method using electroless and electrodeposited Ni/Ag/GDC for SOFC anodes is presented. First a porous Ce0.9Gd0.1O2-x (GDC) scaffold was deposited on a YSZ electrolyte by screen printing and sintering. The scaffold was then metallized with silver using Tollens' reaction, followed by electrodeposition of nickel from a Watt's bath. The electrodes (Ni/Ag/GDC) were tested in both symmetrical and fuel cell configurations. The microstructures of the Ni/Ag/GDC anodes were analyzed using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX). Nano-particles of Ni formed in the porous GDC scaffold provided triple phase boundaries (TPB). The electronic conductivity of the Ni/Ag/GDC (3.5/24.7/71.8 vol%) electrode was good even at relatively low Ni volume fractions. The electrochemical performance was examined in different concentrations of humidified hydrogen (3% H2O) and over a range of temperatures (600-750 °C). The total area specific resistance (ASR) of the anode at 750 °C in humidified 97 vol% H2 was 1.12 Ω cm2, with low-frequency polarization (R-l) as the largest contributor. The electrodes were successfully integrated into a fuel cell and operated in both H2 and syngas. © 2016 The Authors.