title: Hole-transporting small molecules based on thiophene cores for high efficiency perovskite solar cells.
abstract: 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.
authors.affiliation: Energy Research Institute @ NTU (ERI@N), School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 637553.
authors.forename: Hairong
authors.initials: H
authors.lastname: Li
authors.forename: Kunwu
authors.initials: K
authors.lastname: Fu
authors.forename: Pablo P
authors.initials: PP
authors.lastname: Boix
authors.forename: Lydia H
authors.initials: LH
authors.lastname: Wong
authors.forename: Anders
authors.initials: A
authors.lastname: Hagfeldt
authors.forename: Michael
authors.initials: M
authors.lastname: Grätzel
authors.forename: Subodh G
authors.initials: SG
authors.lastname: Mhaisalkar
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Grimsdale
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D058266:Dielectric Spectroscopy; D011211:Electric Power Supplies; D009682:Magnetic Resonance Spectroscopy; D010087:Oxides / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013472:Sunlight; D013876:Thiophenes / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; D013876:Thiophenes; C059910:perovskite; D014025:Titanium
keywords: dyes/pigments; electrochemistry; heterocycles; perovskite phases; solar cells