Suppressing Deep Traps in PbS Colloidal Quantum Dots via Facile Iodide Substitutional Doping for Solar Cells with Efficiency >10%

Surface passivation of PbS colloidal quantum dots (QDs) with iodide has been used in highly efficient solar cells. Iodide passivation is typically achieved by ligand exchange processes on QD films. Complementary to this approach, herein we present a non-intrusive solution-based strategy for doping Q...

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Detalles Bibliográficos
Autores: Stavrinadis, Alexandros, Pradhan, Santanu, Papagiorgis, Paris, Itskos, Grigorios, Konstantatos, Konstantatos
Tipo de recurso: artículo
Fecha de publicación:2017
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:2117/101781
Acceso en línea:https://hdl.handle.net/2117/101781
Access Level:acceso abierto
Palabra clave:Quantum dots
Quantum Dots
Cèl·lules solars
Àrees temàtiques de la UPC::Física
Descripción
Sumario:Surface passivation of PbS colloidal quantum dots (QDs) with iodide has been used in highly efficient solar cells. Iodide passivation is typically achieved by ligand exchange processes on QD films. Complementary to this approach, herein we present a non-intrusive solution-based strategy for doping QDs with iodide to further optimize solar cell performance. The doping step is applied in-situ at the end of the synthesis of the QDs. The optimum precursor I/Pb ratio is found to be in the 1.5-3% range at which iodide substitutes S without excessively altering the dots´ surface chemistry. This allows for band engineering and decreasing the density of deep trap states of the QDs which taken together lead to PbS QD solar cells with efficiency in excess of 10%.