title: Investigation of hydrogen induced fluorescence in C60and its potential use in luminescence down shifting applications.
abstract: Herein the photophysical properties of hydrogenated fullerenes (fulleranes) synthesized by direct hydrogenation utilizing hydrogen pressure (100 bar) and elevated temperatures (350 °C) are compared to the fulleranes C60H18and C60H36synthesized by amine reduction and the Birch reduction, respectively. Through spectroscopic measurements and density functional theory (DFT) calculations of the HOMO-LUMO gaps of C60Hx(0 ≤ x ≤ 60), we show that hydrogenation significantly affects the electronic structure of C60by decreasing conjugation and increasing sp3hybridization. This results in a blue shift of the emission maximum as the number of hydrogen atoms attached to C60increases. Correlations in the emission spectra of C60Hxproduced by direct hydrogenation and by chemical methods also support the hypothesis of the formation of C60H18and C60H36during direct hydrogenation with emission maxima of 435 and 550 nm respectively. We also demonstrate that photophysical tunability, stability, and solubility of C60Hxin a variety of organic solvents make them easily adaptable for application as luminescent down-shifters in heads-up displays, light-emitting diodes, and luminescent solar concentrators. The utilizization of carbon based materials in these applications can potentially offer advantages over commonly utilized transition metal based quantum dot chromophores. We therefore propose that the controlled modification of C60provides an excellent platform for evaluating how individual chemical and structural changes affect the photophysical properties of a well-defined carbon nanostructure.
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: J A
authors: JA
authors: Teprovich
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: A L
authors: AL
authors: Washington
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: J
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authors: Dixon
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: P A
authors: PA
authors: Ward
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: J H
authors: JH
authors: Christian
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: B
authors: B
authors: Peters
authors: Virginia Commonwealth University, Physics Department, Richmond, VA 23284, USA.
authors: J
authors: J
authors: Zhou
authors: National Institute of Technology Rourkela, Department of Chemistry, Odisha 769008, India.
authors: S
authors: S
authors: Giri
authors: University of Tennessee, Department of Chemistry, Knoxville, TN 37996, USA.
authors: D N
authors: DN
authors: Sharp
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: J A
authors: JA
authors: Velten
authors: University of Tennessee, Department of Chemistry, Knoxville, TN 37996, USA.
authors: R N
authors: RN
authors: Compton
authors: Virginia Commonwealth University, Physics Department, Richmond, VA 23284, USA.
authors: P
authors: P
authors: Jena
authors: Savannah River National Laboratory, Aiken, SC 29808, USA. joseph.teprovich@srs.gov ragaiy.zidan@srnl.doe.gov.
authors: R
authors: R
authors: Zidan