BODIPY based A-D-A molecules: Effect of CF3 group substitution at meso phenyl group

Tarafdar, G and Johnson, JC and Larson, BW and Ramamurthy, PC (2020) BODIPY based A-D-A molecules: Effect of CF3 group substitution at meso phenyl group. In: Dyes and Pigments, 177 .

	PDF dye_pig_177_2020.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy
	Microsoft Word 1-s2.0-S0304416520300519-mmc1.doc - Published Version Download (5MB)

Abstract

Two pairs of A-D-A molecules have been synthesized with fluorene and benzodithiophene as the central donor subunits and terminal BODIPY units, functionalized with either a 4-methylphenyl or 4-trifluoromethylphenyl group at the meso position. The effect of the para substituent of the meso phenyl group on the photophysical properties of these molecules is studied through steady state absorption and fluorescence spectroscopy as well as femtosecond transient absorption and time resolved fluorescence spectroscopy techniques. Applicability of these molecules as donors in solution processed solar cell active layers was investigated through time resolved microwave conductivity measurements on blends with PC60BM acceptor, which shows a varying yield of charge transfer with choice of substituent. Transient absorption spectroscopy is then employed to investigate the role of the 4-trifluoromethylphenyl group in altering the efficiency of charge transfer from these A-D-A molecules to PC60BM. The results show a consistent picture of picosecond charge transfer and a component of a few hundred ps geminate recombination that results in a small yield of long-lived free charges optimized for the methylphenyl derivatives. © 2020 Elsevier Ltd

Item Type:	Journal Article
Publication:	Dyes and Pigments
Publisher:	ELSEVIER SCI LTD
Additional Information:	The copyright of this article belongs to ELSEVIER SCI LTD
Keywords:	Absorption spectroscopy; Charge transfer; Fluorescence; Fluorescence spectroscopy; Molecules, 4-trifluoromethylphenyl groups; Femtosecond transient absorption; Geminate recombination; Photophysical properties; Steady-state absorption; Time-resolved fluorescence spectroscopy; Time-resolved microwave conductivities; Transient absorption spectroscopies, Synthesis (chemical)
Department/Centre:	Division of Interdisciplinary Sciences > Interdisciplinary Centre for Energy Research
Date Deposited:	25 Jun 2020 07:26
Last Modified:	25 Jun 2020 07:26
URI:	http://eprints.iisc.ac.in/id/eprint/64811

Actions (login required)

View Item