Zhang Zhen-Long, Li Jun-Feng, Wang Xiao-Li, Qin Jian-Qiang, Shi Wen-Jia, Liu Yue-Feng, Gao Hui-Ping, Mao Yan-Li
School of Physics and Electronics, Henan University, Kaifeng, 475004, China.
Institute for Computational Materials Science, Henan University, Kaifeng, 475004, China.
Nanoscale Res Lett. 2017 Dec;12(1):43. doi: 10.1186/s11671-016-1811-0. Epub 2017 Jan 17.
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.
本文采用水热法合成了氮掺杂二氧化钛（N-TiO）纳米棒阵列，并将其用作电子传输层制备了钙钛矿太阳能电池。通过改变氮掺杂含量对太阳能电池性能进行了优化。基于氮掺杂含量为1%（N/Ti，原子比）的N-TiO的太阳能电池的功率转换效率达到了11.1%，比基于未掺杂TiO的太阳能电池高出14.7%。为深入了解这种改进，进行了一些研究。用X射线粉末衍射（XRD）检测结构，用扫描电子显微镜（SEM）检测形貌。能量色散谱仪（EDS）和Tauc图光谱表明氮已掺入TiO纳米棒中。吸收光谱显示N-TiO对可见光的吸收比未掺杂的TiO更高。氮掺杂使能带隙从3.03 eV降低到2.74 eV。光致发光（PL）和时间分辨光致发光（TRPL）光谱显示，与未掺杂的TiO相比，电子从钙钛矿层转移到N-TiO的速度更快。电化学阻抗谱（EIS）显示基于N-TiO的器件电阻比基于未掺杂TiO的器件电阻更小。
