†State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China.
‡Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
J Am Chem Soc. 2015 Jun 17;137(23):7282-5. doi: 10.1021/jacs.5b03740. Epub 2015 Jun 8.
We designed and synthesized the DPPEZnP-TEH molecule, with a porphyrin ring linked to two diketopyrrolopyrrole units by ethynylene bridges. The resulting material exhibits a very low energy band gap of 1.37 eV and a broad light absorption to 907 nm. An open-circuit voltage of 0.78 V was obtained in bulk heterojunction (BHJ) organic solar cells, showing a low energy loss of only 0.59 eV, which is the first report that small molecule solar cells show energy losses <0.6 eV. The optimized solar cells show remarkable external quantum efficiency, short circuit current, and power conversion efficiency up to 65%, 16.76 mA/cm(2), and 8.08%, respectively, which are the best values for BHJ solar cells with very low energy losses. Additionally, the morphology of DPPEZnP-TEH neat and blend films with PC61BM was studied thoroughly by grazing incidence X-ray diffraction, resonant soft X-ray scattering, and transmission electron microscopy under different fabrication conditions.
我们设计并合成了 DPPEZnP-TEH 分子，该分子通过乙炔桥将卟啉环连接到两个二酮吡咯并吡咯单元上。所得到的材料表现出非常低的能带隙为 1.37eV，并且具有宽的光吸收至 907nm。在体异质结（BHJ）有机太阳能电池中获得了 0.78V 的开路电压，显示出仅 0.59eV 的低能量损耗，这是小分子太阳能电池显示能量损耗<0.6eV 的首次报道。优化后的太阳能电池表现出显著的外量子效率、短路电流和功率转换效率，分别高达 65%、16.76mA/cm(2)和 8.08%，这是具有非常低能量损耗的 BHJ 太阳能电池的最佳值。此外，通过掠入射 X 射线衍射、共振软 X 射线散射和在不同制备条件下的透射电子显微镜，深入研究了 DPPEZnP-TEH 纯膜和与 PC61BM 共混膜的形态。
