Haji-Khan Mirzaei Leila, Shahroosvand Hashem, Farokhi Afsaneh, Bayat Elahe, Bellani Sebastiano, Anichini Cosimo, Ameri Mohsen, Bonaccorso Francesco
Group for Molecular Engineering of Advanced Functional Materials (GMA), Chemistry Department, University of Zanjan, 45617 Zanjan, Iran.
BeDimensional S.p.A., Via Lungotorrente Secca 3D, 16163 Genova, Italy.
ACS Omega. 2024 Dec 5;9(50):49132-49142. doi: 10.1021/acsomega.4c05440. eCollection 2024 Dec 17.
The engineering of charge transport materials, with electronic characteristics that result in effective charge extraction and transport dynamics, is pivotal for the realization of efficient perovskite solar cells (PSCs). Herein, we elucidate the critical role of terminal substituent methoxy groups (-OCH) on the bandgap tuning of the spiro-like hole transport materials (HTMs) to realize performant and cost-effective PSCs. By considering spiro-OMeTAD as the benchmark HTM, we kept the backbone of spiro while replacing diphenylamine with phenanthrenimidazole. This approach significantly decreases the cost of spiro-OMeTAD by reducing the cost of the ancillary group from 0.051 to 0.012 $/g. By increasing the number of methoxy groups on the ancillary ligand from four to eight, the power conversion efficiency (PCE) of the corresponding PSCs containing dopants passed from 17.10% to 18.70%, approaching the value achieved using spiro-OMeTAD containing dopants (PCE = 19.26%). Remarkably, the devices based on dopant-free spiro-OMeTAD have shown a significant loss of PCE, which decreased from 12.9% to 10.1% after 300 h (to 8.2% after 600 h) of light soaking at an open circuit voltage. On the contrary, the cells based on the designed dopant-free HTM demonstrated optimal PCE retention, experiencing a minor drop from 14.4% to 14.1% and 13.2% after 300 and 600 h, respectively, of light soaking at open-circuit voltage.
电荷传输材料的工程设计，其电子特性能够实现有效的电荷提取和传输动力学，对于实现高效的钙钛矿太阳能电池（PSC）至关重要。在此，我们阐明了末端取代基甲氧基（-OCH）对螺环类空穴传输材料（HTM）的带隙调节的关键作用，以实现高性能且具有成本效益的PSC。以螺环-OMeTAD作为基准HTM，我们保留了螺环的主链，同时用菲并咪唑取代二苯胺。这种方法通过将辅助基团的成本从0.051美元/克降低到0.012美元/克，显著降低了螺环-OMeTAD的成本。通过将辅助配体上的甲氧基数量从四个增加到八个，含掺杂剂的相应PSC的功率转换效率（PCE）从17.10%提高到18.70%，接近使用含掺杂剂的螺环-OMeTAD所达到的值（PCE = 19.26%）。值得注意的是，基于无掺杂剂螺环-OMeTAD的器件显示出PCE的显著损失，在开路电压下光照浸泡300小时后从12.9%降至10.1%（600小时后降至8.2%）。相反，基于设计的无掺杂剂HTM的电池表现出最佳的PCE保持率，在开路电压下光照浸泡300小时和600小时后，分别从14.4%轻微下降到14.1%和13.2%。
