title: Green-Emitting Gd3Ga5O12: Tb3+Nanoparticles Phosphor: Synthesis, Structure, and Luminescence.
abstract: Nano- and microceramics of Gd3Ga5O12garnet doped with 1 mol % Tb3+ions were synthesized via co-precipitation and high-temperature solid-state reaction methods. X-ray diffraction measurements confirmed the formation of the garnet structure with Ia3d space group in all investigated samples. Atomic force microscopy surface images and grain-size distribution diagrams of Gd3Ga5O12: 1 mol % Tb3+nanoceramics with 300 and 400 g/mol of polyethylene glycol (PEG) were obtained. The relationship between the content of polyethylene glycol and the particle size of Gd3Ga5O12: Tb3+phosphors was revealed. An intense broad band (λm= 266 nm) related to spin-allowed 4f8-4f75d1transitions of Tb3+ions was found in photoluminescence excitation spectra of Gd3Ga5O12: Tb3+nanocrystalline ceramics with PEG-300 and PEG-400 at 300 K. The broad excitation band caused by spin-forbidden (λm= 295 nm) 4f-5d transitions in Tb3+ions was additionally observed in the photoluminescence excitation spectra of Gd3Ga5O12: Tb3+microceramics. Emission of Tb3+ions under X-ray and UV excitations is presented by two groups of sharp lines which correspond to5D3and5D4→7Fjtransitions of Tb3+ions with the most intense line at 546 nm (5D4→7F5). It was established that the increasing of PEG content leads to the decreasing of the X-ray and photoluminescence emission intensities.
authors.affiliation: Department of Sensor and Semiconductor Electronics, Ivan Franko National University of Lviv, Tarnavskogo St. 107, 79017, Lviv, Ukraine. luchechko@electronics.lnu.edu.ua.
authors.forename: A
authors.initials: A
authors.lastname: Luchechko
authors.affiliation: Department of Sensor and Semiconductor Electronics, Ivan Franko National University of Lviv, Tarnavskogo St. 107, 79017, Lviv, Ukraine.
authors.forename: L
authors.initials: L
authors.lastname: Kostyk
authors.affiliation: Department of Organic Chemistry, Lviv Polytechnic National University, Bandera St. 12, 79013, Lviv, Ukraine.
authors.forename: S
authors.initials: S
authors.lastname: Varvarenko
authors.affiliation: Department of Sensor and Semiconductor Electronics, Ivan Franko National University of Lviv, Tarnavskogo St. 107, 79017, Lviv, Ukraine.
authors.forename: O
authors.initials: O
authors.lastname: Tsvetkova
authors.affiliation: Department of Sensor and Semiconductor Electronics, Ivan Franko National University of Lviv, Tarnavskogo St. 107, 79017, Lviv, Ukraine.
authors.forename: O
authors.initials: O
authors.lastname: Kravets
keywords: Co-precipitation method; Excitation spectra; Gd3Ga5O12 garnet; Nano- and microceramics; Nanoparticles; Photoluminescence; Polyethylene glycol (PEG); Tb3+ ions; X-ray luminescence