Nano-assembly Pd anchoring in the non-stoichiometric spongy zinc ferrite to catalyze the electro-oxidation of C1 organic compounds

In the polymeric fuel cell, improving the efficiency of the electrodes is one of the challenges to commercialize this technology. The utilization of spongy support is an efficient and novel approach for uniform dispersion of nano-metallic electrocatalyst and increasing the active surface area. In this work, the non-stoichiometric spongy zinc ferrite (NSZF) has been synthesized by the solution combustion technique. The scanning electron microscopy, X-ray diffraction, and N-2 ad-/de-sorption test have proven the production of pure cubic spinel ZnFe1.6O4 phase with a spongy morphology and average grains size 11.9 nm. Nano-assembled palladium (NAPd) has been anchored on NSZF as a ceramic support via wet processing, and used in the anodic oxidation of single-carbon organic compounds, such as methanol, formaldehyde, and formic acid. The stability and CO-tolerance ability of NAPd-NSZF have been represented by comparing with NAPd as non-supported palladium. The NSZF as a transition metal oxide has effective property in the dispersion of NAPd in its porous structure. The NSZF promotes NAPd ability for the elimination of carbonaceous intermediates blocking of the catalyst active site through the surface oxygens, and creation of the cycling redox between the high and low valences of iron. The chronoamperometry study has been displayed the higher catalytic activity of NAPd-NSZF in comparison with NAPd for the electrooxidation of single-carbon organic compounds.