Intermetallic Pd3X (X= Ti and Zr) nanocrystals for electro-oxidation of alcohols and formic acid in alkaline and acidic media

• Main Authors: Rajesh Kodiyath, Gubbala V. Ramesh, Maidhily Manikandan, Shigenori Ueda, Takeshi Fujita, Hideki Abe
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2020-01-01
• Series: Science and Technology of Advanced Materials
• Subjects: pd3ti nanoparticles; pd3zr nanoparticles; intermetallic compounds; electro-oxidation; fuel cells
• Online Access: http://dx.doi.org/10.1080/14686996.2020.1789437

Two highly active and stable Pd-based intermetallic nanocrystals with early d-metals Pd3Ti and Pd3Zr have been developed. The nanocrystals are synthesized by co-reduction of the respective salts of Pd and Ti/Zr. Hard X-ray photoemission Spectroscopy (HAXPES) analysis of the nanocrystals indicates that the electronic properties of Pd are modified significantly, as evident from the lowering of the d-band center of Pd. The intermetallic nanocrystals dispersed in Vulcan carbon, Pd3Ti/C and Pd3Zr/C, exhibit improved electrocatalytic activity towards methanol and ethanol oxidation in an alkaline medium (0.5 M KOH), compared to those of commercially available catalysts such as Pd/C, Pt/C, and Pt3Sn/C. In addition, Pd3Ti/C and Pd3Zr/C show significantly higher activity towards the oxidation of formic acid in an acidic medium (0.5 M H2SO4), compared to those of Pd/C and Pt/C. The modification of the d-band center of Pd as a result of the alloying of Pd with the early d-metals Ti and Zr may be responsible for the enhanced catalytic activity.