Pd–Ni(OH)2 nanocatalyst on Ketjen black carbon as a potential alternative to commercial Pt-catalysts for oxygen reduction reactions

Abstract

Recently, the oxygen reduction reaction (ORR) in fuel cells has been considered as an environmental-friendly and efficient technology in energy conversion systems and the field of energy storage. Herein, we propose a facile and cost-effective method for synthesizing Pd–Ni(OH)2 nanocatalysts on Ketjen black carbon as an alternative to commercial Pt/C catalysts. First, the Pd–Ni(OH)2/C nanocatalyst prepare using a sonochemical and solvothermal method. Then, the Pd–Ni(OH)2/C nanocatalyst analysis using transmission electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma optical emission spectrometry (ICP-OES). Pd–Ni(OH)2 nanoparticles with sizes of approximately 5 nm well disperse on the Ketjen black carbon. XRD use to clarify face-centered cubic Pd and amorphous Ni(OH)2. The valence states of Pd and Ni(OH)2 confirm using XPS. The amounts of Pd and Ni in the nanocatalyst are 12.14 and 2.21 wt%, respectively, from ICP. Pd–Ni(OH)2/C exhibits high performance in linear sweep voltammetry for the ORR. In addition, long-term stability and methanol tolerance confirm via chronoamperometry experiments in an alkaline solution. Pd–Ni(OH)2/C exhibits better durability than that of commercial Pt/C. The high current density, durability, and methanol resistance of Pd–Ni(OH)2/C present a potential alternative to Pt/C in proton exchange membrane fuel cells and direct methanol fuel cells through a facile and cost-effective synthesis method.