Tricolor devices based on Ba2SiO4:Eu3+and/or Tb3+: sol-gel synthesis and eletrophoretic deposition for W-leds application

• Grant number: 17/21995-1
• Support type: Scholarships abroad - Research Internship - Doctorate (Direct)
• Effective date (Start): February 10, 2018
• Effective date (End): February 09, 2019
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal researcher: Ana Maria Pires
• Grantee: Airton Germano Bispo Júnior
• Supervisor abroad: Luis Antonio Ferreira Martins Dias Carlos
• Home Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil
• Research place: Universidade de Aveiro (UA), Portugal
• Associated to the scholarship: 16/20421-9 - Tricolor devices based on Ba2SiO4:Eu3+ e/ou Tb3+: sol-gel synthesis and eletrophoretic deposition for W-LEDs application, BP.DD

Abstract

The current global concern about energy production and the demand for more efficient forms of light has led scientists to develop new materials for application in solid-state lighting devices. In this sense, white light sources from light emitting diodes (LEDs) are considered the new generation of illumination due to the high emission efficiency, longer lifetime, greater reproducibility of the emitted light, reduction of emission of UV radiation and relatively lower operating temperatures compared to fluorescent and incandescent lamps. In LEDs, white light can be obtained by combining red, green, yellow or blue phosphors that when excited by a UV or blue light emitting chip give the viewer a sense of white light. However, these commercial devices have presented some disadvantages such as relatively low color rendering index and low color temperature stability. In this sense, this work is being proposed to manufacture light emitting diodes using commercially available LEDs and fluorescent light emitting light blue, green, yellow or red based on Ba2SiO4 doped with Eu3 +, Eu2 +, Tb3 + or Dy3 +. The Eu3 + and Tb3 + doped phosphors were previously synthesized by the sol-gel methodology during the initial two years of the candidate's doctorate and the doping with Eu2 + and Dy3 + will be performed at the University of Aveiro. For the LED emitting layer building, two methodologies will be tested, the first one involving electrophoretic deposition and the second the deposition of a suspension of the phosphor in cyanoacrylate via casting. After optimization of the deposition, the composition of the emitter layer will be varied with the different phosphors in order to obtain efficient white light emission. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BISPO-, JR., AIRTON G.; LIMA, SERGIO A. M.; CARLOS, LUIS D.; FERREIRA, RUTE A. S.; PIRES, ANA M. Phosphor -based green -emitting coatings for circadian lighting. Journal of Luminescence, v. 224, AUG 2020. Web of Science Citations: 0.

BISPO-JR, AIRTON G.; LIMA, SERGIO A. M.; CARLOS, LUIS D.; PIRES, ANA M.; FERREIRA, RUTE A. S. Eu(II)-Activated Silicates for UV Light-Emitting Diodes Tuning into Warm White Light. ADVANCED ENGINEERING MATERIALS, MAY 2020. Web of Science Citations: 0.

FANG, MING; BISPO-JR, AIRTON G.; FU, LIANSHE; FERREIRA, RUTE A. S.; CARLOS, LUIS D. Efficient green-emitting Tb3+ -doped di-ureasil coating phosphors for near-UV excited light-emitting diodes. Journal of Luminescence, v. 219, MAR 2020. Web of Science Citations: 0.

BISPO-JR, AIRTON G.; LIMA, SERGIO A. M.; CARLOS, LUIS D.; FERREIRA, RUTE A. S.; PIRES, ANA M. Red-Emitting Coatings forMultifunctional UV/Red Emitting LEDs Applied in Plant Circadian Rhythm Control. ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY, v. 9, n. 1 SEP 20 2019. Web of Science Citations: 1.