Colloidal CuFeS2 Nanocrystals : Intermediate Fe d-Band Leads to High Photothermal Conversion Efficiency

We describe the colloidal hot-injection synthesis of phase-pure nanocrystals (NCs) of a highly abundant mineral, chalcopyrite (CuFeS2). Absorption bands centered at around 480 and 950 nm, spanning almost the entire visible and near-infrared regions, encompass their optical extinction characteristics...

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Veröffentlicht in:Chemistry of materials : a publication of the American Chemical Society. - 1998. - 28(2016), 13 vom: 12. Juli, Seite 4848-4858
1. Verfasser: Ghosh, Sandeep (VerfasserIn)
Weitere Verfasser: Avellini, Tommaso, Petrelli, Alessia, Kriegel, Ilka, Gaspari, Roberto, Almeida, Guilherme, Bertoni, Giovanni, Cavalli, Andrea, Scotognella, Francesco, Pellegrino, Teresa, Manna, Liberato
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2016
Zugriff auf das übergeordnete Werk:Chemistry of materials : a publication of the American Chemical Society
Schlagworte:Journal Article Research Support, Non-U.S. Gov't
Beschreibung
Zusammenfassung:We describe the colloidal hot-injection synthesis of phase-pure nanocrystals (NCs) of a highly abundant mineral, chalcopyrite (CuFeS2). Absorption bands centered at around 480 and 950 nm, spanning almost the entire visible and near-infrared regions, encompass their optical extinction characteristics. These peaks are ascribable to electronic transitions from the valence band (VB) to the empty intermediate band (IB), located in the fundamental gap and mainly composed of Fe 3d orbitals. Laser-irradiation (at 808 nm) of an aqueous suspension of CuFeS2 NCs exhibited significant heating, with a photothermal conversion efficiency of 49%. Such efficient heating is ascribable to the carrier relaxation within the broad IB band (owing to the indirect VB-IB gap), as corroborated by transient absorption measurements. The intense absorption and high photothermal transduction efficiency (PTE) of these NCs in the so-called biological window (650-900 nm) make them suitable for photothermal therapy as demonstrated by tumor cell annihilation upon laser irradiation. The otherwise harmless nature of these NCs in dark conditions was confirmed by in vitro toxicity tests on two different cell lines. The presence of the deep Fe levels constituting the IB is the origin of such enhanced PTE, which can be used to design other high performing NC photothermal agents
Beschreibung:Date Completed 19.03.2018
Date Revised 27.03.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:0897-4756
DOI:10.1021/acs.chemmater.6b02192