Thermal oxidation fabrication of NiO film for optoelectronic devices

In this work, NiO coating was fabricated by magnetron sputtering method on quartz and indium tin oxide (ITO) substrates in an inert gas ambient of Ar followed by a thermal oxidation process in air at 400 °C for 2 h. The NiO coating was analyzed by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM), and UV-vis spectrometer. A preliminary photovoltaic performance measurement of the as-prepared device (ITO/NiO/poly-TPD/PC71BM/Al) shows a short circuit current density (Jsc) of 5.6 mA cm−2 and power conversion efficiency (PCE) of 1.5% under an illumination of 100 mW cm−2. The PCE of device with NiO HTLs was ca. 20% higher than those of the devices based on PEDOT:PSS hole transport layers (HTLs). The thermal oxidation fabricated NiO coating may provide an excellent route to fabricate other NiO-based optoelectronic devices.