title: Donor-Acceptor Control in Grown-in-Glass Gallium Oxide Nanocrystals by Crystallization-driven Heterovalent Doping.
abstract: Incorporation of doping ions in nanocrystals is a strategy for providing nanophases with functions directly related to ion features. At the nanoscale, however, doping can also activate more complex effects mediated by perturbation of the nanophase size and structure. Here, we report a paradigmatic case in which we modify grown-in-glass γ-Ga2O3nanophases by nickel or titanium doping of the starting glass, so as to control the concentration of oxygen and gallium vacancies responsible for the light emission. Optical absorption and luminescence show that Ni2+and Ti4+ions enter into the nanophase, but differential scanning calorimetry and X-ray diffraction indicate that Ni and Ti also work as modifiers of nanocrystal growth. As a result, doping influences nanocrystal size and concentration, which in turn dictate the number of donors and acceptors per nanocrystal. Finally, the chain of effects turns out to control both the intensity and spectral distribution of the light emission.
authors.affiliation: Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125, Milano, Italy.|P.D. Sarkisov Int. Laboratory of Glass-based Functional Materials, Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125190, Moscow, Russia.
authors.forename: Alberto
authors.identifier: http://orcid.org/0000-0002-6590-9739
authors.initials: A
authors.lastname: Paleari
authors.affiliation: P.D. Sarkisov Int. Laboratory of Glass-based Functional Materials, Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125190, Moscow, Russia.
authors.forename: Nikita V
authors.initials: NV
authors.lastname: Golubev
authors.affiliation: P.D. Sarkisov Int. Laboratory of Glass-based Functional Materials, Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125190, Moscow, Russia.
authors.forename: Elena S
authors.initials: ES
authors.lastname: Ignat'eva
authors.affiliation: P.D. Sarkisov Int. Laboratory of Glass-based Functional Materials, Mendeleev University of Chemical Technology of Russia, Miusskaya Square 9, 125190, Moscow, Russia.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Sigaev
authors.affiliation: Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125, Milano, Italy.
authors.forename: Angelo
authors.identifier: http://orcid.org/0000-0001-9768-4573
authors.initials: A
authors.lastname: Monguzzi
authors.affiliation: Department of Materials Science, University of Milano-Bicocca, via R. Cozzi 55, 20125, Milano, Italy.
authors.forename: Roberto
authors.identifier: http://orcid.org/0000-0002-6199-0971
authors.initials: R
authors.lastname: Lorenzi
keywords: donor-acceptor systems; doping; glasses; nanocrystals; photophysics