Dependence of power conversion properties of hole-conductor-free mesoscopic perovskite solar cells on the loading of perovskite crystallites

作者：Chen, Hui; Li, Kangming; Liu, Huang; Gao, Yongli; Yuan, Yongbo; Yang, Bingchu; Zhou, Conghua^*

来源：Organic Electronics, 2018, 61: 119-124.

DOI：10.1016/j.orgel.2018.06.054

• Hole-conductor-free
• Carbon
• Concentration
• Life time
• Crystallinity
• Stability

Effect of the loading of perovskite crystallites on the power conversion properties of carbon based hole-conductor-free mesoscopic perovskite solar cells is studied by varying the concentration of the perovskite precursor from 0.3 to 1.0 mol/L (at given volume of 30 mu L). It is observed that, when the concentration is 0.3 mol/L, poor filling is obtained due to relatively low loading of perovskite, and the perovskite solar cells suffer from huge dispersion in efficiencies and large hysteresis index (averaged at 18.29% and up to 34.61%). With increment of the concentration (from 0.4 to 1.0 mol/L), crystallinity of perovskite crystallites is improved according to X-ray diffraction studies, and the lifetime of photo-generated charge carriers is prolonged as reflected by transient photovoltaic (TPV) detection. Meanwhile, the open circuit voltage rises up from 0.86 ( +/- 0.03) V to 0.91 ( +/- 0.01) V, and the hysteresis index is reduced from 10.02 ( +/- 4.67)% to 1.45 ( +/- 2.21)%. However, the film conductance of carbon film is decreased due to the loading of perovskite, which deteriorates the fill factor of the devices. Finally, optimized power conversion efficiency is achieved at moderate concentration or 0.6 mol/L, which is 12.59 ( +/- 0.40) %, compared to 11.81 ( +/- 0.36) % at 1.0 mol/L. Due to the barrier provided by the carbon film against H2O/O-2, all of the devices showed good shelf-stability, though loading of perovskite is varied in these devices.

• 出版日期2018-10
• 单位中南大学