Ultrafast singlet fission dynamics in polymer-based thin-films measured by femtosecond transient absorption spectroscopy

Singlet fission is a photophysical process which converts an excited singlet state into two independent triplet states. This has attracted significant attention for photovoltaic devices due to the fact that more than one electron can be generated per each absorbed photon, which can boost the quantum...

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Detalles Bibliográficos
Autor: Caravaca Crespo, Eva
Tipo de recurso: tesis de maestría
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/377307
Acceso en línea:https://hdl.handle.net/2117/377307
Access Level:acceso abierto
Palabra clave:Flash photolysis
Photovoltaic power generation
Thin films
transient absorption spectroscopy
organic photovoltaics
singlet fission
thin films
Fotoquímica
Energia solar fotovoltaica
Capes fines
Àrees temàtiques de la UPC::Física::Física de l'estat sòlid
Descripción
Sumario:Singlet fission is a photophysical process which converts an excited singlet state into two independent triplet states. This has attracted significant attention for photovoltaic devices due to the fact that more than one electron can be generated per each absorbed photon, which can boost the quantum efficiency over 100 %. In this project, research on the understanding of singlet fission dynamics of organic thin films has been conducted by using transient absorption spectroscopy as the main characterisation method of the proposed polymer-based films, which are a mixture of TIPS-pentacene and Y6. Results have shown that charge generation is due to the triplet states generated thanks to the excitation at 800 nm of TIPS-pentacene in blends at certain ratios. Moreover, as an extra work, solar cells have been fabricated obtaining a 10 % of quantum efficiency due only to the triplet states generation.