Thermal decomposition approach for the synthesis of silver–alumina nanocomposite powders

Silver–alumina nanocomposite powders have been synthesized by a simple thermal decomposition approach using silver acetate and alumina. The effect of using nanocrystalline versus macro-crystalline alumina during the preparation of the nanocomposites has been investigated. The nanocomposites were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, thermal gravimetric analysis, surface area measurements, field emission scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy and diffuse reflectance spectroscopy. The characterization results indicate the presence of silver nanoparticles on the surface of alumina and nanocrystalline alumina acts as a better support for the dispersion of silver nanoparticles compared to the macro-crystalline alumina. The silver–alumina nanocomposite powders have been explored as catalysts for the reduction of 4-nitrophenol.