Photocurrent-detected 2D electronic spectroscopy reveals ultrafast hole transfer in operating PM6/Y6 organic solar cells
The performance of nonfullerene-acceptor-(NFA)-based organic solar cells is rapidly approaching the efficiency of inorganic cells. The chemical versatility of NFAs extends the light-harvesting range to the infrared, while preserving a considerably high open-circuit- voltage, crucial to achieve power...
| Autores: | , , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2021 |
| 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:2117/366043 |
| Acceso en línea: | https://hdl.handle.net/2117/366043 https://dx.doi.org/10.1021/acs.jpclett.1c00822 |
| Access Level: | acceso abierto |
| Palabra clave: | Optoelectronic devices Photovoltaic cells Emission spectroscopy Nonfullerene-acceptor-(NFA) Electron transfer Dispositius optoelectrònics Àrees temàtiques de la UPC::Física |
| Sumario: | The performance of nonfullerene-acceptor-(NFA)-based organic solar cells is rapidly approaching the efficiency of inorganic cells. The chemical versatility of NFAs extends the light-harvesting range to the infrared, while preserving a considerably high open-circuit- voltage, crucial to achieve power-conversion efficiencies >17%. Such low voltage losses in the charge separation process have been attributed to a low-driving-force and efficient exciton dissociation. Here, we address the nature of the subpicosecond dynamics of electron/hole transfer in PM6/Y6 solar cells. While previous reports focused on active layers only, we developed a photocurrent-detected two-dimensional spectroscopy to follow the charge transfer in fully operating devices. Our measurements reveal an efficient hole-transfer from the Y6- acceptor to the PM6-donor on the subpicosecond time scale. On the contrary, at the same time scale, no electron-transfer is seen from the donor to the acceptor. These findings, putting ultrafast spectroscopy in action on operating optoelectronic devices, provide insight for further enhancing NFA solar cell performance. |
|---|