Abstract:
In this work, CuI thin films were prepared by using a liquid iodination method. The effects of time (i.e., 1, 2, 3, 4 and 5 min) for the reaction between a copper (Cu) precursor and an iodine solution at room temperature, and Cu or Cu3N reactants on the structural, electrical and optical properties of the CuI thin films were elucidated systematically. For the first case, the XRD result revealed that the as-prepared films with the different reaction times displayed polycrystallinity of zinc blende structure with preferentially oriented along the (111) planes. The synthesized film with the 1 min reaction time showed the maximum values of optical transmittance (56.69 %) and conductivity (5.46 Scm-1). In another experiment, the Cu3N thin films were soaked in the iodine solution for 1 min. The obtained CuI films were identically formed into the crystalline structure and the preferential plane as compared to those of the pristine CuI films. Besides, the optical and electrical investigation pointed out that the nitrogen atom in the Cu3N precursor significantly affected the properties of films. The CuI films derived from the reaction of Cu3N film and iodine solution exhibited the highest conductivity (29.36 Scm-1), and large transmittance over 75 % in the visible region. Therefore, these findings would assist researchers in the rapid synthesis of CuI thin films to utilize as transparent electronic devices.