Facile synthesis of a highly active Pd/Co bimetallic nanocatalyst on carbon fiber cloth via a two-step electrodeposition for formic acid electrooxidation

• Published in: Journal of solid state electrochemistry 2015-01, Vol.19 (1), p.289-298
• Main Authors: Vafaei, Maral, Rezaei, Milad, Tabaian, Seyed Hadi, Mahboubi, Farzad, Haghshenas, Davoud Fatmehsari
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Electrochemistry; Energy Storage; Original Paper; Physical Chemistry
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-014-2561-5

A facile and immediate two-step electrodeposition method was employed to fabricate a carbon fiber cloth (CFC) coated with Pd deposited on Co nanoparticles (NPs), with Co deposition time of 100 s (denoted as Pd/Co 100 /CFC). For the sake of comparison, Pd/Co 10 /CFC and Pd/CFC were prepared by the same method. The characterization was carried out using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and electrochemical techniques. The FESEM micrographs and XRD results revealed that an increase in Co deposition time results in a change in deposited Pd morphology from dendritic to fine and dispersed NPs, a noticeable reduction in size of Pd NPs, a rise in percentage of alloying, and contraction strain in the Pd/Co 100 /CFC structure. The Pd/Co 100 /CFC catalyst showed a mass activity of j p  = 1,220 mA mg Pd ‐ 1 for formic acid (FA) electrooxidation, and it had 69.1 m 2  g −1 electrochemical active surface area (ECSA), which are more than eight and three times higher than those of Pd/CFC catalyst ( j P  = 140 mA mg Pd ‐ 1 , ECSA = 22.8 m 2  g −1 ), respectively. Moreover, comparison of the performance parameters of Pd/Co 100 /CFC with some other palladium-based electrodes in some recent studies with relatively good results showed that the Pd/Co 100 /CFC has a great potential as a less expensive, fast and easily prepared, and dramatically active anodic electrocatalyst in the application of direct formic acid fuel cells.