Orange/Red Benzo[1,2-b:4,5-bī]dithiophene 1,1,5,5-Tetraoxide-Based Emitters for Luminescent Solar Concentrators: Effect of Structures on Fluorescence Properties and Device Performances
Year: 2023
Authors: Matteo Bartolini; Cosimo Micheletti; Alberto Picchi; Carmen Coppola; Adalgisa Sinicropi; Mariangela Di Donato; Paolo Foggi; Alessandro Mordini; Gianna Reginato; Andrea Pucci; Lorenzo Zani; Massimo Calamante
Autors Affiliation: CNR ICCOM, Inst Chem Organometall Cpds, I-50019 Sesto Fiorentino, Italy; Univ Pisa, Dept Chem & Ind Chem, I-56124 Pisa, Italy; Univ Siena, Dept Biotechnol, R2ES Lab Chem & Pharm, I-53100 Siena, Italy; CSGI, Consorzio Sviluppo Sistemi & Grande Interfas, I-50019 Sesto Fiorentino, Italy; LENS, European Lab Non Linear Spect, I-50019 Sesto Fiorentino, Italy; Natl Inst Opt CNR INO, Sesto Fiorentino, Italy; Univ Florence, Dept Chem U Schiff, I-50019 Sesto Fiorentino, Italy; Inst Chem Organometall Cpds CNR ICCOM, I-50019 Sesto Fiorentino, Italy.
Abstract: Luminescent solar concentrators (LSCs) are a class of optical devices able to harvest, downshift, and concentrate sunlight, thanks to the presence of emitting materials embedded in a polymer matrix. Use of LSCs in combination with silicon-based photovoltaic (PV) devices has been proposed as a viable strategy to enhance their ability to harvest diffuse light and facilitate their integration in the built environment. LSC performances can be improved by employing organic fluorophores with strong light absorption in the center of the solar spectrum and intense, red-shifted emission. In this work, we present the design, synthesis, characterization, and application in LSCs of a series of orange/red organic emitters featuring a benzo[1,2-b:4,5-b?]dithiophene 1,1,5,5-tetraoxide central core as an acceptor (A) unit. The latter was connected to different donor (D) and acceptor (A?) moieties by means of Pd-catalyzed direct arylation reactions, yielding compounds with either symmetric (D-A-D) or non-symmetric (D-A-A?) structures. We found that upon light absorption, the compounds attained excited states with a strong intramolecular charge-transfer character, whose evolution was greatly influenced by the nature of the substituents. In general, symmetric structures showed better photophysical properties for the application in LSCs than their non-symmetric counterparts, and using a donor group of moderate strength such as triphenylamine was found preferable. The best LSC built with these compounds presented photonic (external quantum efficiency of 8.4 +- 0.1%) and PV (device efficiency of 0.94 +- 0.06%) performances close to the state-of-the-art, coupled with a sufficient stability in accelerated aging tests.
Journal/Review: ACS APPLIED ENERGY MATERIALS
Volume: 6 (9) Pages from: 4862 to: 4880
More Information: We thank “COLOURS” project, funded by Regione Toscana (POR FESR 2014 -2020, grant no. 3553.04032020.158000411), “SUNNYSIDE” project, funded by Fondazione Cassa di Risparmio di Firenze (grant no. 2020.1408), and project ” nuovi Concetti, mAteriali e tecnologie per līiNtegrazione del fotoVoltAico negli edifici in uno scenario di generazione diffuSa” (“CANVAS”), funded by the Italian Ministry of the Environment and the Energy Security, through the Research Fund for the Italian Electrical System (type-A call, published on G.U.R.I. n. 192 on 18-082022), for financial support. This research was also funded by the European Unionīs Horizon 2020 Research and Innovation program under grant agreement no. 871124 Laserlab-Europe. S. Desbrousses is acknowledged for his assistance in the preparation of compound BDT-H2.KeyWords: luminescent solar concentrators, organic emitters, benzodithiophene tetraoxide, DFT calculations, transient absorption spectroscopy, photovoltaicsDOI: 10.1021/acsaem.3c00362Citations: 11data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-10-20References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here