White-emitting silicates doped with lanthanide and transition metal ions for application in warm white-light-emitting diodes

• Grant number: 20/02614-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2021
• End date: February 28, 2023
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Marian Rosaly Davolos
• Grantee: Marian Rosaly Davolos
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated researchers: Airton Germano Bispo Júnior ; Ana Maria Pires ; Luís António Ferreira Martins Dias Carlos ; Maria Rute de Amorim e Sá Ferreira André ; Sergio Antonio Marques de Lima

Abstract

White-light-emitting diodes (WLEDs) are currently the main white light sources for lighting, traffic light or backlighting of displays due to their long lifespan (50,000 h), brightness (800 lm) and luminous efficacy (150 lm·w-1), low power consumption (8.5 W), coast-benefit (60 dollars over 20 years of use) and environmentally friendly properties compared to incandescent and fluorescent lamps. However, some drawbacks related to the quality of the white color still need to be addressed since the main commercially available WLED features a blueish white color, classified as cool white color that is dangerous to humans considering the circadian rhythm regulation. To overcome such issues, new strategies based on the fabrication of WLEDs by combining near-UV-emitting LEDs and single-phased white-emitting phosphors have emerged within the solid-state lighting field. In this case, the main challenges lie on the synthesis of phosphors that match high emission quantum yield (> 50 %), high thermal stability of luminescence and emission of white color featuring high color rendering index (> 90) and low correlated color temperature (3.000 K) ideal for nigh lighting. Thus far, this project deals with the synthesis of new single-phased white-emitting phosphors based on Sr3SiO5 or Ca2MgSi2O7 doped with Ce3+, Tb3+ and Eu3+ or Ce3+, Eu2+ and Mn2+, aiming to take advantage of the blue emission of Ce3+, green emission of Tb3+ and red emission of Eu3+ or the blue emission of Ce3+, green emission of Eu2+ and red emission of Mn2+ within these hosts. Ce3+ also acts as sensitizer for the Eu3+, Tb3+ and Mn2+ luminescence. The main challenge of this propose is the optimization of the doping concentration in order to favor the energy transfer processes, leading to the emission of white light featuring high emission quantum yield. The phosphors will be combined with near-UV-emitting LEDs, fabricating WLEDs displaying correlated color temperature (< 3.500 K), color rendering index (> 90) and luminous efficacy (> 100 lm·W 1) required for applications of warm WLEDs in night lighting. (AU)

Scientific publications

(7)

(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)

BELTRAME, ARIANE C. F.; BISPO, AIRTON G. G.; CANISARES, FELIPE S. M.; FERNANDES, RICARDO V.; LAURETO, EDSON; LIMA, SERGIO A. M.; PIRES, ANA M.. PMMA or PVDF films blended with beta-diketonate tetrakis Eu-III or Tb-III complexes used as downshifting coatings of near-UV LEDs. SOFT MATTER, v. 19, n. 22, p. 10-pg., 2023-04-25. (20/02614-0, 19/26103-7)

BISPO-JR, AIRTON GERMANO; MAZALI, ITALO ODONE; SIGOLI, FERNANDO APARECIDO. Single-center Ln(III) ratiometric luminescent temperature probes based on singlet -> singlet and singlet -> triplet sensitizations. JOURNAL OF MATERIALS CHEMISTRY C, v. 10, n. 38, p. 8-pg., 2022-08-15. (12/11382-9, 13/22127-2, 21/06326-1, 20/02614-0)

BISPO, AIRTON GERMANO; MORAIS, AMANDA JUSTINO DE; CALADO, CLAUDIA MANUELA SANTOS; MAZALI, ITALO ODONE; SIGOLI, FERNANDO APARECIDO. Lanthanide-doped luminescent perovskites: A review of synthesis, properties, and applications. Journal of Luminescence, v. 252, p. 16-pg., 2022-10-19. (12/11382-9, 13/22127-2, 20/02614-0)

DE MORAIS, AMANDA JUSTINO; BISPO-JR, AIRTON GERMANO; FERREIRA, FLAVIA DE SOUSA; MAZALI, ITALO ODONE; SIGOLI, FERNANDO APARECIDO. Multi-emission processes of hierarchically structured NaGdF4:Tm:Yb:Tb core@shell nanoparticles. NEW JOURNAL OF CHEMISTRY, v. 47, n. 15, p. 8-pg., 2023-03-20. (20/02614-0, 21/08111-2, 21/06326-1)

BISPO-JR, AIRTON G.; SARAIVA, LEONARDO F.; LIMA, SERGIO A. M.; PIRES, ANA M.; DAVOLOS, MARIAN R.. Recent prospects on phosphor-converted LEDs for lighting, displays, phototherapy, and indoor farming. Journal of Luminescence, v. 237, SEP 2021. (19/19337-1, 20/02614-0)

LIMA, DEBORAH A.; BISPO JR, AIRTON G.; GALICO, DIOGO A. .; COELHO, SERGIO F. N.; NETO, JOAO H. ARAUJO; ELLENA, JAVIER A.; PETIOTE, LANOUSSE; MAZALI, ITALO O.; SIGOLI, FERNANDO A. .. Tuning the Thermometric Features in 1D Luminescent EuIII and TbIII Coordination Polymers through Different Bridge Phosphine Oxide Ligands. Inorganic Chemistry, v. 62, n. 17, p. 9-pg., 2023-04-17. (21/04876-4, 20/02614-0, 21/08111-2, 17/08098-0, 21/06326-1)

BISPO-JR, AIRTON G.; MAZALI, ITALO O.; SIGOLI, FERNANDO A.. Sensitization of lanthanide complexes through direct spin-forbidden singlet -> triplet excitation. Physical Chemistry Chemical Physics, v. 24, n. 22, p. 6-pg., 2022-05-12. (12/11382-9, 13/22127-2, 20/02614-0)