Facile star-shaped tetraphenylethylene-based molecules with fused ring-terminated diarylamine as interfacial hole transporting materials for inverted perovskite solar cells. (14th December 2020)

• Record Type: Journal Article
• Authors: Chen, Yung-Chung; Lin, Ding-Zhi; Wang, Jhong-Ci; Ni, Jen-Shyang; Yu, Yang-Yen; Chen, Chih-Ping
• Is Part Of: Materials chemistry frontiers. Volume 5:Number 3(2021)
• Page Start: 1373
• Page End: 1387
• Publication Date: 2020-12-14
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/d0qm00728e
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : Three p-type small molecules (CL-1–3 ) based on tetraphenylethylene as the core and different π-conjugation diarylamines as linkers are synthesized. The bilayer HTL of the NiOx/CL-3 -based cell exhibits the best power conversion efficiency of 20.15%. Abstract : In this work, three p-type small molecules (CL-1–3 ) based on tetraphenylethylene as the core and fused ring-terminated diarylamine as electron donating groups were synthesized. The design strategy for fused ring-terminated diarylamines involved the use of benzene for CL-1, naphthalene for CL-2, and pyrene for CL-3 . We then investigated the effects of various electron-donating groups on their electronic properties. Among them, the CL-3 sample showed the highest T g value (192 °C) and 5 wt% decomposition temperature (473 °C). In the presence of urea as an additive, inverted perovskite solar cells (PSCs) employing inorganic/organic (NiOx/CL series) bilayer HTLs and reference inorganic (NiOx)-only HTL were fabricated. Notably, the NiOx/CL-3 -based cell exhibited the champion power conversion efficiency of 20.15%, which outperformed the NiOx-only cell (PCE = 18.66%) due to its smoother surface morphology, better interface charge transfer and matched energy-level alignment. Furthermore, this device also exhibited greater hydrophobicity and acceptable long-term stability. This work presents a new molecular design and in-depth understanding of the bilayer HTL strategy and its potential for the development of highly efficient cell performances.