Electrochemical Activation and NAP-XPS As Well As EIS Characterization of La_0.31Sr_0.58Ti_0.97Ni_0.03O_3-δ Thin Film Electrode

Abstract

To improve catalytic activity of LaxSr0.9-xTiyM1-yO3-δ, La1-xSrxCryM1-yO3-δ based materials, doping of perovskite B-site with metals (M) like Ni, Co, Mo or Cu has been proposed. It has been demonstrated, that at elevated temperatures and in reducing atmosphere these dopants exsolve to perovskite surface and form nanometer scale catalyst particles. Exsolution process could be accelerated by using electrochemical polarization. In the present study thin film La0.31Sr0.58Ti0.97Ni0.03O3-δ electrodes was prepared using pulsed laser deposition (PLD) technique. Current collectors were made from Pt (using magnetron sputtering) and placed under the thin film electrode layer. Electrodes were characterized using XPS and EIS method at near ambient pressure conditions (1-5 mbar) at 650 °C, activated electrochemically and characterized again to see the effect of activation. Changes on the electrochemical performance as well as on XPS data caused by electrochemical activation were observed and analyzed.