Soochow Institute for Energy and Materials InnovationS, College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, and ‡Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University , Suzhou 215006, China.
ACS Appl Mater Interfaces. 2017 Sep 20;9(37):31746-31751. doi: 10.1021/acsami.7b06681. Epub 2017 Sep 5.
4,7-Diphenyl-1,10-phenanthroline (Bphen) is an efficient electron transport and hole blocking material in organic photoelectric devices. Here, we report cesium carbonate (CsCO) doped Bphen as cathode interfacial layer in CHNHPbICl based planar perovskite solar cells (PSCs). Investigation finds that introducing CsCO suppresses the crystallization of Bphen and benefits a smooth interface contact between the perovskite and electrode, resulting in the decrease in carrier recombination and the perovskite degradation. In addition, the matching energy level of Bphen film in the PSCs effectively blocks the holes diffusion to cathode. The resultant power conversion efficiency (PCE) achieves as high as 17.03% in comparison with 12.67% of reference device without doping. Besides, experiments also demonstrate the stability of PSCs have large improvement because the suppressed crystallization of Bphen by doping CsCO as a superior barrier layer blocks the Ag atom and surrounding moisture access to the vulnerable perovskite layer.
4,7-二苯基-1,10-菲咯啉（Bphen）是有机光电设备中有效的电子传输和空穴阻挡材料。在这里，我们报告了碳酸铯（CsCO）掺杂的 Bphen 作为基于 CHNHPbICl 的平面钙钛矿太阳能电池（PSC）的阴极界面层。研究发现，引入 CsCO 抑制了 Bphen 的结晶，并有利于钙钛矿和电极之间的平滑界面接触，从而减少了载流子复合和钙钛矿降解。此外，Bphen 薄膜在 PSCs 中的匹配能级有效地阻止了空穴向阴极的扩散。与未掺杂的参考器件 12.67%的效率相比，该器件的功率转换效率（PCE）高达 17.03%。此外，实验还证明了 PSCs 的稳定性有了很大的提高，因为掺杂 CsCO 的 Bphen 的抑制结晶作为一个优良的阻挡层阻止了 Ag 原子和周围的水分进入脆弱的钙钛矿层。
