Enhancement of Perovskite Solar Cells Efficiency using N-Doped TiO 2 Nanorod Arrays as Electron Transfer Layer

• Published in: Nanoscale research letters 2017-12, Vol.12 (1), p.43
• Main Authors: Zhang, Zhen-Long, Li, Jun-Feng, Wang, Xiao-Li, Qin, Jian-Qiang, Shi, Wen-Jia, Liu, Yue-Feng, Gao, Hui-Ping, Mao, Yan-Li
• Format: Article
• Language: English
• ISSN: 1931-7573
• DOI: 10.1186/s11671-016-1811-0

In this paper, N-doped TiO (N-TiO ) nanorod arrays were synthesized with hydrothermal method, and perovskite solar cells were fabricated using them as electron transfer layer. The solar cell performance was optimized by changing the N doping contents. The power conversion efficiency of solar cells based on N-TiO with the N doping content of 1% (N/Ti, atomic ratio) has been achieved 11.1%, which was 14.7% higher than that of solar cells based on un-doped TiO . To get an insight into the improvement, some investigations were performed. The structure was examined with X-ray powder diffraction (XRD), and morphology was examined by scanning electron microscopy (SEM). Energy dispersive spectrometer (EDS) and Tauc plot spectra indicated the incorporation of N in TiO nanorods. Absorption spectra showed higher absorption of visible light for N-TiO than un-doped TiO . The N doping reduced the energy band gap from 3.03 to 2.74 eV. The photoluminescence (PL) and time-resolved photoluminescence (TRPL) spectra displayed the faster electron transfer from perovskite layer to N-TiO than to un-doped TiO . Electrochemical impedance spectroscopy (EIS) showed the smaller resistance of device based on N-TiO than that on un-doped TiO .