Synthesis of Pd/α-Fe2O3 nanocomposites for catalytic CO oxidation

Iron oxide and metal doped iron oxide nanocomposites have found attractive and versatile applications in many research areas such as catalysts, sensors, and biomedicine. This work reports a surfactant-free hydrolysis approach for the synthesis of hematite (α-Fe2O3) and Pd doped α-Fe2O3 nanoparticles with low-temperature catalytic activity. By this method, iron oxide rod-like nanoparticles were achieved by hydrolysis of ferric chloride salt with dilute HCl at a temperature of 100 °C. The Pd/iron oxide nanocomposites were obtained by adding citric acid into a mixture of iron oxide nanoparticles and palladium precursor (Pd(CH3CN)2Cl2) under a reflux heating at 90 °C for 2 h. This method is featured as no use of any surfactants and templates, and no requirement of high-temperature thermal decomposition that are usually required for shape/size control in polar or nonpolar solvents. More importantly, it was found that the Pd/α-Fe2O3 nanocomposites exhibited high low-temperature catalytic activity in carbon monoxide (CO) oxidation.