ENHANCED AND SYNERGISTIC CATALYSIS OF ONE-POT SYNTHESIZED PALLADIUM-NICKEL ALLOY NANOPARTICLES FOR ANODIC OXIDATION OF METHANOL IN ALKALI

In search for cost effective catalysts capable to oxidize methanol efficiently, nearly mono dispersed PdxNiy binary electro catalysts of varying mutual composition have been synthesized using classical wet chemical protocol in a single pot in absence of any capping agent. The obtained PdxNiy nanoalloys are stable in dispersion and powder form. The X-ray diffraction, spectroscopic and microscopic studies reveal crystallites with diameter of ca 5 nm are agglomerated in nearly spherical shape on the base carbon electrode. The synthesized material shows enhanced synergistic effect in catalysis of methanol oxidation reaction in alkali and the alloy containing 20 atom % of Ni seems to be the best for fuels like methanol, formaldehyde unlike sodium formate whose oxidation is catalysed at best by C/Pd electrode. The C/PdxNiy catalysts are significantly protected from poisoning, leading to the excellent electrocatalytic activity. Cyclic voltammograms of possible intermediates like formaldehyde, sodium formate and ex-situ FTIR, chromatographic (HPLC) studies of reaction products reveal that Ni accelerates formation of carbonate rather than formate elucidating the plausible mechanism of the reaction. (C) 2017 Elsevier Ltd. All rights reserved.