Efficient ceramic anodes infiltrated with binary and ternary electrocatalysts for SOFCs operating at low temperatures

摘要

Electrocatalyst precursor of various combinations: Pt, Ru, Pd, Ni and Gd-doped CeO_2 (CGO) were infiltrated into a porous Sr_(0.94)Ti_(0.9)Nb_(0.1)O_3 (STN) backbone, to study the electrode performance of infiltrated ceramic anodes at low temperature ranges of 400-600 ℃. The performance of the binary electrocatalyst infiltrated ceramic backbones are Pt-CGO>Ru-CGO>Pd-CGO>Ni-CGO. Ternary electrocatalyst of Ni -Pd-CGO and Ni-Pt-CGO showed the lowest polarization resistance of 0.31 and 0.11 Ωcm~2, respectively at 600 ℃ in H_2/3% H_2O. The average particle size of the ternary electrocatalyst was larger than the binary Pd-CGO and Pt-CGO due to the particle coarsening of Ni nanoparticles. High resolution transmission electron microscopic analysis on the best performing Ni-Pt-CGO electrocatalyst infiltrated anode reveals the formation of Ni-Pt nanocrystalline alloy and a homogenous distribution of nanoparticles on STN backbone.