Abstract
The aim of the project is to unravel the mechanism of Singlet Fission - a process by which a photoexcited singlet state splits into a pair of free triplets, thus rendering conceivable single-junction devices beyond the Shockley-Queisser limit in terms of power conversion efficiency - in small poly-heteroaromatic chromophores in solution and thin films by combining tailored synthesis, advanced spectroscopy and theoretical modelling. In particular, utrafast transient absorption and two-dimensional electronic spectroscopy experiments, paired with advanced electronic structure calculations, quantum dynamics and spectroscopy simulations from first principles, will be carried out. The long-term goal of SiFi-MYSTERY is to disentangle some of the unsolved aspects governing the ultrafast molecular mechanism of SF. Specifically, we aim at resolving the role of intermediate dark states in the “triplet pair” formation and in the generation of free triplets in thin films. Si-Fi will go beyond the state-of-the-art by applying multidimensional vibronic quantum dynamics relying on Hamiltonians parametrized from first principles based on multiconfiguration wave function theory and explicitly considering solvent effect. On the experiment side state-of-the-art ultrafast transient absorption and 2D electronic spectroscopy experiments with unprecedented temporal resolution (sub-10 fs) and ultra-broad spectral coverage (UV to near IR) will be performed. The research will be realized on newly synthesized organic chromophores functionalized with electron-withdrawing and -donating groups facilitating a systematic tuning of the electronic structure. Through this synergetic network, theoretically and experimentally motivated design criteria for enhancing singlet fission yield will be aspired to and incorporated in the synthesis.
Dettagli del progetto
Responsabile scientifico: Artur Nenov
Strutture Unibo coinvolte:
Dipartimento di Chimica Industriale "Toso Montanari"
Coordinatore:
ALMA MATER STUDIORUM - Università di Bologna(Italy)
Contributo totale di progetto: Euro (EUR) 239.682,00
Contributo totale Unibo: Euro (EUR) 150.640,00
Durata del progetto in mesi: 24
Data di inizio
30/11/2023
Data di fine:
28/02/2026
