Synthesis of Cu-YSZ and Ni-Cu-YSZ cermets by a novel electroless technique for use as solid oxide fuel cell anode: Application potentiality towards fuel flexibility in biogas atmosphere

A novel electroless technique is employed for synthesizing Cu-YSZ cermet with discrete deposition of Cu onto 8 mol% yttria-stabilized zirconia (YSZ) and alloyed with 90 weight % Ni using electroless Ni-YSZ cermet by mechanical mixing and heat treatment under controlled atmosphere for the application as solid oxide fuel cell anode. X-ray diffractograms using Lorentzian fits revealed a shift of Ni-Cu (111) and Ni-Cu (200) peaks suggesting the solid solution of the bimetallic phases. Unique core-shell microstructures for both CuYSZ and Ni-Cu-YSZ with YSZ as core and Cu/Ni-Cu as shell are observed. EDAX analyses confirms 90:10 weight ratios (Ni:Cu) in the shell position for the alloy cermet. While only 23 vol% of metal content in Cu-YSZ gives electrical conductivity of 700 S cm(-1), a reasonably high value of 490 S cm(-1) is obtained with 32 vol% of metal in Ni-Cu-YSZ. Electroless Ni-CuYSZ exhibits 98% efficiency towards methane reforming in simulated biogas environment and also shows significant tolerance to H2S (upto 25 ppm) in the input stream of the gas. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.