Y-doping TiO2 nanorod arrays for efficient perovskite solar cells

To improve the electron transportation in TiO2 nanorod arrays and charge separation in the interface of TiO2/perovskite, Y-doping TiO2 nanorod arrays with the length of 200 nm, diameter of 11 nm and areal density of 1050 mu m(2) were successfully prepared by the hydrothermal method and the influence of Y/Ti molar ratios of 0%, 3%, 5% in the hydro thermal grown solutions on the growth of TiO2 nanorod arrays was investigated. The results revealed that the appropriate Y/Ti molar ratios can increase the areal density of the corresponding TiO2 nanorod arrays and improve the charge separation in the interface of the TiO2/perovskite. The Y-doping TiO2 nanorod array perovskite solar cells with the Y/Ti molar ratio of 3% exhibited a photoelectric conversion efficiency (PCE) of 18.11% along with an open-circuit voltage (V-oc) of 1.06 V, short-circuit photocurrent density (J(sc)) of 22.50 mA cm(-2) and fill factor (FF) of 76.16%, while the un-doping TiO2 nanorod array perovskite solar cells gave a PCE of 16.42% along with V-oc of 1.04 V.J(sc) of 21.66 mA cm(-2) and FF of 72.97%. (C) 2018 Elsevier Ltd. All rights reserved.