Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels

doi:https://doi.org/10.1016/0025-5408(94)90094-9

Title: Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels

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Abstract

Phosphor performance is often limited by preparation conditions which determine the degree of crystallinity and structural order. The influence of vacancy disorder was investigated using magnesium aluminate and magnesium gallate spinels as test cases. Spinels of composition Mg[sub 1[minus]x]Al[sub 2]O[sub 4[minus]x]:Mn[sup 2+] and Mg[sub 1[minus]x]Ga[sub 2]O[sub 4[minus]x]:Mn[sup 2+] where 0 < x < 0.2 form defect solid solutions in which the loss of the divalent cation is compensated by the formation of both anion and cation vacancies. Defect and normal/inverse disorder was probed by comparing the emission and excitation spectra of Mn[sup 2+]. MgAl[sub 2]O[sub 4]:Mn[sup 2+] emits at 650 nm. When x = 0.05, emission bands appear at 517 and 744 nm. These increase intensity and the 650 nm band disappears as x increases. The emission of the magnesium gallate phosphors was a single band at 507 nm for all compositions. Overall, the emission spectra were determined more by the distribution of Mn[sup 2+] over the available sites than by either normal/inverse disorder or defect disorder.

Authors:

Mohler, R L; White, W B ^[1]

Pennsylvania State Univ., University Park, PA (United States). Materials Research Lab.

Publication Date:: 1994-10-01

OSTI Identifier:: 6889131

Resource Type:: Journal Article

Journal Name:: Materials Research Bulletin; (United States)

Additional Journal Information:: Journal Volume: 29:10; Journal ID: ISSN 0025-5408

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; ALUMINIUM OXIDES; CRYSTAL STRUCTURE; LUMINESCENCE; GALLIUM OXIDES; MAGNESIUM OXIDES; CRYSTAL DEFECTS; EMISSION SPECTRA; MANGANESE; ALKALINE EARTH METAL COMPOUNDS; ALUMINIUM COMPOUNDS; CHALCOGENIDES; ELEMENTS; GALLIUM COMPOUNDS; MAGNESIUM COMPOUNDS; METALS; OXIDES; OXYGEN COMPOUNDS; SPECTRA; TRANSITION ELEMENTS; 360202* - Ceramics, Cermets, & Refractories- Structure & Phase Studies; 360204 - Ceramics, Cermets, & Refractories- Physical Properties

Citation Formats


                    Mohler, R L, and White, W B. Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels.  United States: N. p., 1994. 
        Web.  doi:10.1016/0025-5408(94)90094-9.

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                    Mohler, R L, & White, W B. Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels.  United States.  https://doi.org/10.1016/0025-5408(94)90094-9

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                    Mohler, R L, and White, W B. Sat .  
        "Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels".  United States.  https://doi.org/10.1016/0025-5408(94)90094-9.

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@article{osti_6889131,

  title        = {Influence of structural order on the luminescence of oxide spinels: Manganese activated spinels},

  author       = {Mohler, R L and White, W B},

  abstractNote = {Phosphor performance is often limited by preparation conditions which determine the degree of crystallinity and structural order. The influence of vacancy disorder was investigated using magnesium aluminate and magnesium gallate spinels as test cases. Spinels of composition Mg[sub 1[minus]x]Al[sub 2]O[sub 4[minus]x]:Mn[sup 2+] and Mg[sub 1[minus]x]Ga[sub 2]O[sub 4[minus]x]:Mn[sup 2+] where 0 < x < 0.2 form defect solid solutions in which the loss of the divalent cation is compensated by the formation of both anion and cation vacancies. Defect and normal/inverse disorder was probed by comparing the emission and excitation spectra of Mn[sup 2+]. MgAl[sub 2]O[sub 4]:Mn[sup 2+] emits at 650 nm. When x = 0.05, emission bands appear at 517 and 744 nm. These increase intensity and the 650 nm band disappears as x increases. The emission of the magnesium gallate phosphors was a single band at 507 nm for all compositions. Overall, the emission spectra were determined more by the distribution of Mn[sup 2+] over the available sites than by either normal/inverse disorder or defect disorder.},

  doi          = {10.1016/0025-5408(94)90094-9},

  url          = {https://www.osti.gov/biblio/6889131},
  journal      = {Materials Research Bulletin; (United States)},

  issn         = {0025-5408},

  number       = ,

  volume       = 29:10,

  place        = {United States},

  year         = {1994},

  month        = {10}

}

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