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The ability to control the size and composition of metal or alloys nanoparticles is important in preparing catalysts. This paper reports a colloidal synthesis methodology for the preparation of monodisperse palladium−copper (Pd−Cu) alloy nanoparticles with an average diameter of 3 nm for the as-prepared particles and 5−10 nm upon removal of the capping agents. Our approach involves the use of metal precursors, capping agents, and reducing agents in controlled ratios for nanoparticle formation in a single organic phase, followed by deposition of the capped nanoparticles on high surface area carbon and removal of the capping agents via heat treatment in either oxidizing or reducing atmosphere. The results of characterizations using transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), temperature programmed oxidation and reduction combined with mass spectrometry (TPO/TPR-MS), powder X-ray diffraction (XRD), and cyclic voltammetry (CV) are discussed. The resulting high-surface-area-carbon-supported Pd−Cu catalysts (PdCu/C) showed high activity for the oxygen reduction reaction (ORR) in acidic electrolyte. Our study revealed composition and heat-treatment dependent ORR activity.

A unique type of inorganic-organic hybrid semiconductor bulk material is capable of emitting direct white light. Their photoluminescence properties can be tuned precisely and systematically by modifying structures and composition. They could be used as a single-material light-emitting source in high efficiency white-light-emitting diodes.

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