Structural, optical and electrical properties of planar mixed perovskite halides/Al-doped Zinc oxide solar cells

Mixed halide perovskites CH3NH3Pb(I1-xBrx)(3) thin films were successfully fabricated by spin coating using a precursor solution obtained by reacting a (1:1) molar ratio of methyl-ammonium iodide (CH3NH3I) and lead bromide (PbBr2). The films obtained by this one step process were used to fabricate a solar cell using an aluminum-doped Zinc oxide (Al-ZnO) thin film as an electron selective layer. The Al-ZnO films were fabricated by RF sputtering on indium-tin-oxide (ITO) covered glass substrates. The structural and optical properties of the films were analyzed by X-ray diffraction and ultraviolet-visible spectroscopy. The mixed halide pervoskite films were polycrystalline with an optical band gap of 1.85 eV. Al-ZnO/perovskite solar cells were fabricated without a hole-selective layer by directly deposition silver (Ag) contacts on the perovskite films. The electrical properties of the cells were investigated by current voltage (I-V) measurements. The devices showed an open circuit voltage of 0.12 V, a fill factor of 0.29 and conversion efficiency of 1.6% under an illumination of 480 mW cm(-2). The film and cells are stable under ambient atmosphere as revealed by the absence of any changes in their color. (C) 2015 Elsevier B.V. All rights reserved.