A Facile Synthesis of MPd (M = Co, Cu) Nanoparticles and Their Catalysis for Formic Acid Oxidation

Abstract

Monodisperse CoPd nanoparticles (NPs) were synthesized and studied for catalytic formic acid (HCOOH) oxidation (FAO). The NPs were prepared by coreduction of Co(acac)(2) (acac = acetylacetonate) and PdBr(2) at 260 °C in oleylamine and trioctylphosphine, and their sizes (5-12 nm) and compositions (Co(10)Pd(90) to Co(60)Pd(40)) were controlled by heating ramp rate, metal salt concentration, or metal molar ratios. The 8 nm CoPd NPs were activated for HCOOH oxidation by a simple ethanol wash. In 0.1 M HClO(4) and 2 M HCOOH solution, their catalytic activities followed the trend of Co(50)Pd(50) > Co(60)Pd(40) > Co(10)Pd(90) > Pd. The Co(50)Pd(50) NPs had an oxidation peak at 0.4 V with a peak current density of 774 A/g(Pd). As a comparison, commercial Pd catalysts showed an oxidation peak at 0.75 V with peak current density of only 254 A/g(Pd). The synthesis procedure could also be extended to prepare CuPd NPs when Co(acac)(2) was replaced by Cu(ac)(2) (ac = acetate) in an otherwise identical condition. The CuPd NPs were less active catalysts than CoPd or even Pd for FAO in HClO(4) solution. The synthesis provides a general approach to Pd-based bimetallic NPs and will enable further investigation of Pd-based alloy NPs for electro-oxidation and other catalytic reactions.

Electro-oxidation of ethylene glycol and glycerol at palladium-decorated FeCo@Fe core–shell nanocatalysts for alkaline direct alcohol fuel cells: functionalized MWCNT supports and impact on product selectivity

“…For a reliable evaluation of the oxidation products, the anode compartment was sealed under a nitrogen atmosphere, while the cathode was exposed to air or oxygen with no significant variation in the cell performance. The fuel oxidation products were qualitatively and quantitatively determined by 13 C{ 1 H} NMR spectroscopy using appropriate calibration curves. Galvanostatic experiments were carried out at room temperature on the passive cells where the anode compartment was filled with 5 wt% of EG or GLY in 2 M KOH solution.…”

“…Palladium (Pd)-based catalysts are attracting major attention as the most viable materials for ADAFCs. [13][14][15][16] The interest in Pd stems from its natural abundance and low-cost compared to Pt (Pd currently sells at half the price of Pt), [17][18][19][20][21][22][23] and enhanced electrochemical kinetics in alkaline media and ADAFCs than Pt catalysts.…”

Room temperature synthesis of Pd–Cu nanoalloy catalyst with enhanced electrocatalytic activity for the methanol oxidation reaction

“…A few templates [8,20,29,30] have been used for the synthesis of Pd-Cu alloy NPs. The problems with the methods are requirement of higher temperature and lack of stoichiometry of high quality nanostructured Pd-Cu alloy.…”

One – Step synthesis of nitrogen doped reduced graphene oxide with NiCo nanoparticles for ethanol oxidation in alkaline media

“…Up to date, Pd and Pd-based electrocatalysts have continued and most effective for application in DAAFCs because of more abundant of Pd in the earth [1,[3][4]. But, the high capital cost of precious metals (e.g.…”