Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States.
Nano Lett. 2015 Jan 14;15(1):662-8. doi: 10.1021/nl504168q. Epub 2014 Dec 18.
We successfully demonstrated an integrated perovskite/bulk-heterojunction (BHJ) photovoltaic device for efficient light harvesting and energy conversion. Our device efficiently integrated two photovoltaic layers, namely a perovskite film and organic BHJ film, into the device. The device structure is ITO/TiO2/perovskite/BHJ/MoO3/Ag. A wide bandgap small molecule DOR3T-TBDT was used as donor in the BHJ film, and a power conversion efficiency (PCE) of 14.3% was achieved in the integrated device with a high short circuit current density (JSC) of 21.2 mA cm(-2). The higher JSC as compared to that of the traditional perovskite/HTL (hole transporting layer) device (19.3 mA cm(-2)) indicates that the BHJ film absorbs light and contributes to the current density of the device. Our result further suggests that the HTL in traditional perovskite solar cell, even with good light absorption capability, cannot contribute to the overall device photocurrent, unless this HTL becomes a BHJ layer (by adding electron transporting material like PC71BM).
我们成功地展示了一种集成的钙钛矿/体异质结（BHJ）光伏器件，用于高效的光捕获和能量转换。我们的器件有效地将两种光伏层，即钙钛矿薄膜和有机 BHJ 薄膜，集成到器件中。该器件结构为 ITO/TiO2/钙钛矿/BHJ/MoO3/Ag。在 BHJ 薄膜中使用了一个宽带隙小分子 DOR3T-TBDT 作为给体，在集成器件中实现了 14.3%的功率转换效率（PCE），短路电流密度（JSC）高达 21.2 mA cm(-2)。与传统的钙钛矿/HTL（空穴传输层）器件（19.3 mA cm(-2))相比，更高的 JSC 表明 BHJ 薄膜吸收光并为器件的电流密度做出贡献。我们的结果进一步表明，传统钙钛矿太阳能电池的 HTL，即使具有良好的光吸收能力，也不能为整个器件的光电流做出贡献，除非这种 HTL 成为 BHJ 层（通过添加电子传输材料如 PC71BM）。
