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 degrees 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 (J(sc)) 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. (C) 2015 Elsevier B.V. All rights reserved.