Proton conducting CaZr0.9In0.1O3-δ ceramic membrane prepared by tape casting

CaZr0.9In0.1O3-delta ceramics is a good candidate for hydrogen sensing applications due to its protonic conductivity in humid or hydrogen-containing atmospheres combined with high chemical stability and mechanical properties. In order to decrease the material's ohmic resistance and the path length of proton diffusion and thus increasing the efficiency and dynamic response, homogeneous and dense CaZr0.9In0.1O3-delta ceramic membrane was prepared by a tape casting process. The rheological behavior of the slurries and the characterization of the green tape and membrane were carried out. The dispersion of the ceramic powder in the slurry was optimized by ball milling an azeotropic mixture of methyethylketone and ethanol as the solvent, 1 wt.% triethanolamine as the dispersant, polyethylene glycol and dibutyl phthalate as the plasticizer, and 7 wt.% polyvinyl butral as the binder (plasticizer/binder = 1.5:1) for 5 h. The electrical properties of the CaZr0.9In0.1O3-delta membrane in both air and hydrogen were investigated by electrochemical impedance spectroscopy. And a bulk conductivity of 1.3 x 10(-3) S . cm(-1) at 900 degrees C with the activation energy of 0.64 eV for the CaZr0.9In0.1O3-delta membrane in hydrogen were reached. In addition, hydrogen permeation experiment shows that the CaZr0.9In0.1O3-delta membrane is a good proton conductor. (C) 2012 Elsevier B.V. All rights reserved.