Abstract

Galvanic displacement (GD) of electrodeposited (e.d.) copper by palladium in PdSO4+H2SO4 solutions in the absence (solution I) and in the presence (solution II) of copper ions Cu2+ is carried out. The resulting samples are characterized by several methods (SEM, XPS, AES-ICP, etc.). In is found that on freshly formed Pd0(Cu)-I and Pd0(Cu)-II composites, no Pd shell is formed. The copper content is shown to be 10at.% and higher in the surface layer and 22–27% in the bulk (Pd+Cu=100%). Voltammetric and XPS data allow assuming that the surface layer contains mixed oxides (such as PdCuOx) and copper ions which prevent the formation of the Pd shell. Both freshly formed Pd0(Cu) samples and those subjected to potential cycling (0.3–1.2V, RHE) demonstrate the high specific activity in formic acid electrooxidation reaction (FAOR, 1M HCOOH+0.5M H2SO4) which exceeds the activity of e.d. Pd by a factor of 3–4 at 150mV and 8–10 at 300mV. The possible reasons for the higher FAOR activity of Pd in Pd0(Cu) composites are discussed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.