Synthesis and characterization of spinel-type CuAl2O4 nanocrystalline by modified sol–gel method

Nanocrystalline Copper aluminate (CuAl2O4) was prepared by sol–gel technique using aluminum nitrate, copper nitrate, diethylene glycol monoethyl ether and citric acid were used as precursor materials. This method starts from of the precursor complex, and involves formation of homogeneous solid intermediates, reducing atomic diffusion processes during thermal treatment. The formation of pure crystallized CuAl2O4 nanocrystals occurred when the precursor was heat-treated at 600 °C in air for 2 h. The stages of the formation of CuAl2O4, as well as the characterization of the resulting compounds were done using thermo–gravimetric analysis, X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The products were analyzed by transmission electron microscopy and ultraviolet–visible (UV–Vis) spectroscopy to be round, about 17–26 nm in size and Eg = 2.10 eV.