title: Interplay of Internal Structure and Interfaces on the Emitting Properties of Hybrid ZnO Hierarchical Particles.
abstract: The design of hybrid organic/inorganic nanostructures with controlled assembly drives the development of materials with new or improved properties and superior performances. In this paper, the surface and internal structure of hybrid ZnO poly-N-vinylpyrrolidone (ZnO/PVP) mesocrystals are investigated in detail and correlated with their emitting properties. A photoluminescence study at room temperature reveals that the as-synthesized particles show a remarkable ultraviolet (UV) emission, whereas an emission from defects in the visible region is not observed. On the other hand, a visible emission is achieved upon calcination of the hybrid ZnO/PVP particles in air, and its intensity is found to increase with the calcination temperature and, in some cases, to overwhelm the UV emission. A molecular description is proposed for the absence of a visible emission from defects in the as-synthesized ZnO/PVP mesocrystals on the basis of Fourier transform infrared (FTIR) and solid-state13C NMR (SSNMR) spectroscopy. An in-depth electron microscopy study sheds light on the internal organization of mesocrystals and reveals the formation of nanoreactors, that is, particles with enclosed porosity, upon thermal treatment.
authors.affiliation: Institute of Particle Technology, FAU Erlangen-Nuremberg , Cauerstraße, 4, 91058 Erlangen, Germany.|Interdisciplinary Center for Functional Particle Systems, FAU Erlangen-Nuremberg , Haberstraße, 9a, 91058 Erlangen, Germany.
authors.forename: Monica
authors.identifier: http://orcid.org/0000-0002-6177-3811
authors.initials: M
authors.lastname: Distaso
authors.affiliation: IMEM-CNR , Parco Area delle Scienze 37/A, 43124 Parma, Italy.
authors.forename: Giovanni
authors.identifier: http://orcid.org/0000-0001-6424-9102
authors.initials: G
authors.lastname: Bertoni
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica (DICATECh), Politecnico di Bari , Via Orabona 4 (CAMPUS), I-70125 Bari, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Todisco
authors.affiliation: Materials Characterization Facility, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Marras
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica (DICATECh), Politecnico di Bari , Via Orabona 4 (CAMPUS), I-70125 Bari, Italy.
authors.forename: Vito
authors.initials: V
authors.lastname: Gallo
authors.affiliation: Nanochemistry Department, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors.forename: Liberato
authors.identifier: http://orcid.org/0000-0003-4386-7985
authors.initials: L
authors.lastname: Manna
authors.affiliation: Institute of Particle Technology, FAU Erlangen-Nuremberg , Cauerstraße, 4, 91058 Erlangen, Germany.|Interdisciplinary Center for Functional Particle Systems, FAU Erlangen-Nuremberg , Haberstraße, 9a, 91058 Erlangen, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Peukert
keywords: coordination; mesocrystals; nanocomposites; nanoreactors; postprocessing; structure−function relationship