ELECTROCHEMICAL PROPERTIES OF PD-COATED PEROVSKITE CATALYTIC ELECTRODES IN HYBRID SULFUR CYCLE

摘要

Hybrid Sulfur (HyS) cycle, which consists of an electrolysis step and a thermal decomposition one, has been studying as a promising technology for the hydrogen production from water because of CO_2 emission-free process. Exploring low-cost electrode materials with good catalytic activity, excellent electrical conductivity and satisfied corrosion resistance are essential for the practical application of the HyS cycle.Our research group points out that some electronic conductive ceramics, which are Ti-based pyrochlores (A_2~(3+)Ti_2~(4+)O_7, A=lanthanoides) and perovskites (Sr~(2+)Ti~(4+)O_3), might be candidates as the anode substrates with high corrosion resistance. Additionally, it is found that the Pd electroless-deposition on the electronic conductive ceramics is effective for providing the excellent catalytic properties to the anode substrates.In this paper, the electrochemical properties of Ir, Ta and Nb doped non-stoichiometric perovskites covered with Pd thin layer (Pd/Sr_(1-x)Ti_(1-y)M_yO_(3-δ) (M=Ir, Ta, Nb)) were investigated in a 50 weight%H_2SO_4 solution at an operation temperature of 353K.