Synthesis, characterization and optical band gap of La2CuO4 nanoparticles

Pure La2CuO4 nanoparticles were synthesized via sol-gel process using stearic acid as complexing reagent. This method consists of the formation of an organic precursor, with metallic cations homogeneously distributed throughout the matrix. The gel was calcined at 700 °C, 800 °C and 900 °C for 4 h. The as-prepared La2CuO4 nanoparticles were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy and diffuse reflectance spectroscopy. Results show that the purity of La2CuO4 crystallites increases with the increase of heat treatment temperature from 700 °C to 900 °C. Optical properties show that La2CuO4 crystallites have broad absorption in the UV-vis region and the corresponding band gap is 1.24 eV.