Hole-transporting small molecules based on thiophene cores for high efficiency perovskite solar cells

• Main Authors: Mhaisalkar, Subodh Gautam, Li, Hairong, Fu, Kunwu, Boix, Pablo P., Wong, Lydia H., Hagfeldt, Anders, Grätzel, Michael, Grimsdale, Andrew C.
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2014
• Subjects: DRNTU::Science::Chemistry::Physical chemistry::Electrochemistry
• Online Access: https://hdl.handle.net/10356/106665; http://hdl.handle.net/10220/24517
• Institution: Nanyang Technological University

Two new electron-rich molecules, 2,3,4,5-tetra[4,4′-bis(methoxyphenyl)aminophen-4“-yl]-thiophene (H111) and 4,4′,5,5′-tetra[4,4′-bis(methoxyphenyl)aminophen-4”-yl]-2,2′-bithiophene (H112), which contain thiophene cores with arylamine side groups, are reported. When used as the hole-transporting material (HTM) in perovskite-based solar cell devices, power conversion efficiencies of up to 15.4 % under AM 1.5G solar simulation were obtained. This is the highest efficiency achieved with HTMs not composed of 2,2′,7,7′-tetrakis(N,N′-di-p-methoxyphenylamine)-9,9′-spirobifluorene (spiro-OMeTAD) and its isomers. Both HTMs, especially H111, have great potential to replace expensive spiro-OMeTAD given their much simpler and less expensive syntheses.