Photoelectrochemical characteristics of AB5-type hydrogen storage alloy modified with SrTiO3 photocatalyst
(1. Department of Applied Chemistry, Zhejiang University of Technology, Hangzhou 310014, China; 2. Institute of Materials Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, China)
Abstract: Perovskite-type SrTiO3 powders were prepared by using strontium acetate, tetrabutyl titanate and sodium hydroxide via direct hydrolysis-precipitation process. AB5-type hydrogen storage alloy(HSA) electrodes modified with SrTiO3 powders were prepared and the photoelectrochemical characteristics of the as-prepared electrodes were investigated. The results of cyclic voltammograph show that the current of reduction peak increases remarkably under the light irradiation. The obvious photochargeable properties are obtained for the hydrogen storage alloys modified with Perovskite-type SrTiO3 powders. During photocharging process, the potential of the electrode shifts quickly to negative direction and a potential plateau occurs. HSA electrode modified with SrTiO3 powders prepared by direct hydrolysis-precipitation process gives the higher potential of about -0.90V(vs Hg/HgO) under the light irradiation. SEM observation discloses that a large amount of microcracks occur on the surface of the electrode after photocharging process, which is caused by the formation of hydride in the bulk of electrode.
Key words: AB5-type hydrogen storage alloys; SrTiO3 photocatalysts; photoelectrochemical characteristics