Song Zhen, Liu Jiang, Wang Gang, Zuo Wentao, Liao Cheng, Mei Jun
Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang, 621907, China.
Chengdu Green Energy and Green Manufacturing Technology R&D Centre, Chengdu Development Center of Science and Technology, Chengdu, 610200, China.
Chemphyschem. 2017 Nov 3;18(21):3030-3038. doi: 10.1002/cphc.201700910. Epub 2017 Sep 18.
Lead halide perovskite solar cells with remarkable power conversion efficiency have attracted much attention in recent years. However, there still exist many problems with their use that are not completely understood, and further studies are needed. Herein, the hole-transport layer dependence of the photovoltaic performance of perovskite solar cells is investigated in detail. It is found that devices freshly prepared using pristine 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) and Li-doped spiro-OMeTAD as hole-transport layers exhibit S-shaped current density-voltage curves with poor fill factors. The devices show progressively improved fill factors and efficiencies upon exposure to air, which is attributed to air-induced conductivity improvement in the spiro-OMeTAD layer. After introducing a cobalt salt dopant (FK209) into the spiro-OMeTAD layer, the corresponding devices show remarkable performance without the need of air exposure. These results confirm that the dopant not only increases the conductivity of spiro-OMeTAD layer, but also tunes the surface potential, which helps to improve charge transport and reduce the recombination loss.
近年来，具有卓越功率转换效率的卤化铅钙钛矿太阳能电池备受关注。然而，其使用过程中仍存在许多尚未完全了解的问题，需要进一步研究。在此，详细研究了钙钛矿太阳能电池光伏性能对空穴传输层的依赖性。研究发现，使用原始的2,2',7,7'-四（N,N-二对甲氧基苯胺）-9,9'-螺二芴（spiro-OMeTAD）和锂掺杂的spiro-OMeTAD作为空穴传输层新制备的器件呈现出填充因子较差的S形电流密度-电压曲线。这些器件在暴露于空气中时填充因子和效率逐渐提高，这归因于空气中诱导的spiro-OMeTAD层电导率的提高。在向spiro-OMeTAD层引入钴盐掺杂剂（FK209）后，相应的器件无需空气暴露即可表现出卓越的性能。这些结果证实，该掺杂剂不仅提高了spiro-OMeTAD层的电导率，还调节了表面电位，这有助于改善电荷传输并减少复合损失。
