Preparation of delafossite-type CuCrO2 films by sol–gel method

High-quality c-axis oriented delafossite-type CuCrO2 films were successfully prepared by a simple sol–gel method. The microstructure, optical properties as well as room temperature resistivity were studied. It was found that the grain sizes of CuCrO2 films pretreated with different temperatures are different; the films were smooth and consisted of fine particles. The maximal transmittance of CuCrO2 films can reach 70% in the visible region. Optical transmission data of CuCrO2 films indicate a direct band gap and an indirect-gap of about 3.15 eV and 2.66 eV, respectively. The carrier mobility of the films pretreated at 300 °C is smaller than that of the films pretreated at a higher temperature, because of the stronger carrier scattering.

► High-quality c-axis oriented delafossite-type CuCrO2 films were successfully prepared by a simple sol–gel method.
► The films were smooth and consisted of fine particles. The maximal transmittance of CuCrO2 films can reach 70% in the visible region.
► Optical transmission data of CuCrO2 films indicate a direct band gap of 3.15 eV.
► The carrier mobility of the films pretreated at 300 °C is smaller than that of the films pretreated at a higher temperature, because of the stronger carrier scattering.