为了提高有机太阳能电池(OSCs)的性能, 增强器件在空气中的稳定性, 研究了TiO2薄膜作为阴极缓冲层对OSCs器件性能的影响。制备了结构为ITO/TiO2/C70/Rubrene/MoO3/Al的OSCs器件。首先, 通过测量器件效率, 考察了TiO2薄膜对Rubrene/C70电池的性能影响。接着, 通过控制TiO2薄膜厚度, 研究了TiO2厚度对器件性能的影响。实验结果显示, 当TiO2修饰层厚度比较薄时, 器件的各性能参数较低, 随着TiO2厚度的不断增加, 器件的各性能参数呈上升趋势; 当TiO2厚度为81 nm时, 器件的各性能参数达到最佳, 器件的功率转换效率为1.09%, 电流密度为2.55 mA·cm-2, 开路电压为0.88 V, 填充因子为48.69%; 当TiO2厚度继续增加时, 器件的各性能参数开始下降。对比没有TiO2阴极修饰层的器件, 最优时的Jsc、Voc、FF和PCE分别提高了37%、21%、17%和91%, 并阐述了性能提高的原因。

To improve the performance of organic solar cells (OSCs) and enhance their stability in the air, the effect of TiO2 film as cathode buffer layer on the performance of OSCs was studied. The cells with a structure of ITO/TiO2/C70/Rubrene/MoO3/Al were fabricated. The influence of TiO2 on the cell was investigated by measuring the device efficiency. The experimental results show that the performance of cell is on the rise with the increase of the thickness of TiO2. when the thickness of TiO2 is 81 nm, the performance parameters are the best (power conversion efficiency current density, open circuit voltage and fill factor are 1.09%, 2.55 mA·cm-2, 0.88 V, 48.69%, respectively), and the cell performance declines with the continued increasing of TiO2 thickness. Compared with the device without TiO2 layer, the optimal Jsc, Voc, FF and PCE of the cells increased by 37%, 21%, 17% and 91%, respectively. and the reasons for the improvement were discussed.