Dopant-free novel hole-transporting materials based on quinacridone dye for high-performance and humidity-stable mesoporous perovskite solar cells

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 7; no. 10; pp. 5315 - 5323
• Main Authors: Pham, Hong Duc, Jain, Sagar M., Li, Meng, Manzhos, Sergei, Feron, Krishna, Pitchaimuthu, Sudhagar, Liu, Zhiyong, Motta, Nunzio, Wang, Hongxia, Durrant, James R., Sonar, Prashant
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2019
• Subjects: Additives; Devices; Dopants; Dyes; Humidity; Perovskites; Photovoltaic cells; Relative humidity; Solar cells; Titanium dioxide; Transportation
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/C8TA11361K

This study reports three newly developed dopant-free hole-transporting materials (HTMs) for perovskite solar cells. The design is based on a quinacridone (QA) dye as the core with three different extended end-capping moieties, namely, acenaphthylene (ACE), triphenylamine (TPA) and diphenylamine (DPA), attached to the QA core. These HTMs were synthesized and used to successfully fabricate in mesoscopic TiO 2 /CH 3 NH 3 PbI 3 /HTM perovskite devices. Under AM 1.5G illumination at 100 mW cm −2 , the devices achieved a maximum efficiency of 18.2% for ACE-QA-ACE , 16.6% for TPA-QA-TPA and 15.5% for DPA-QA-DPA without any additives, whereas reference devices with doped spiro-OMeTAD as the HTM achieved a PCE of 15.2%. Notably, the unencapsulated devices based on the novel dopant-free HTMs exhibited impressive stability in comparison with the devices based on doped spiro-OMeTAD under a relative humidity of 75% for 30 days. These linear symmetrical HTMs pave the way to a new class of organic hole-transporting materials for cost-efficient and large-area applications of printed perovskite solar cells.