Mechanochemical Synthesis of YFeO3 Nanoparticles: Optical and Electrical Properties of Thin Films

Nanoparticles (NPs) of orthorhombic YFeO 3 , has been successfully synthesized via an uncomplicated mechanochemical method from yttrium and iron chloride salts in a basic medium. The YFeO 3 NPs were characterized by micro-Raman and Fourier-transform infrared spectroscopy. Their crystalline structure and average diameter of 30 nm was determined from X-ray powder diffraction pattern and by transmission electron microscopy images. Thin films (TF) of these NPs in polystyrene were prepared by spin coating in order to study their electrical and optical properties, as well as to verify their possible application in the manufacture of optoelectronic devices. UV–visible diffuse reflectance was performed for YFeO 3 NPs and for YFeO 3 TF and optical band gaps of 2.38 and 3.7 eV, respectively, were estimated from optical absorption measurements. The electrical conductivity of the YFeO 3 TF was evaluated in a glass/ITO/YFeO 3 TF/Ag device. At low voltages, electric current in the forward direction was found to obey an ohmic I–V relationship; at higher voltages, the behavior of the film in the device is defined by a Space Charge Limited Current model and, at around 1 V, current saturation. These results suggest the possibility of using YFeO 3 TF in the production of dielectric layers in electronic or optoelectronic devices.