YAMAGATA, CHIEKOMORAIS, VINICIUS R.MELLO-CASTANHO, SONIA R.H.2021-01-262021-01-26YAMAGATA, CHIEKO; MORAIS, VINICIUS R.; MELLO-CASTANHO, SONIA R.H. New sol-gel method for synthesis of Dy-doped yttrium disilicate phosphor not from TEOS but sodium silicate solution. In: PACIFIC RIM CONFERENCE OF CERAMIC SOCIETIES, 13th, October 27 - November 1, 2019, Okinawa, Japan. <b>Abstract...</b> Disponível em: http://200.136.52.105/handle/123456789/31777.http://200.136.52.105/handle/123456789/31777Yttrium disilicate/pyrosilicate (Y2Si2O7), which occurs naturally as yttrialite, is a mixture of rare earth silicates that displays interesting structural properties because of its high refractoriness (mp = 1775 °C) and stability in oxidizing environments. Yttrium disilicate offers a wide band gap and excellent thermal and chemical stability compared to other well-studied phosphors such as ZnS and CdS. It has been shown to be one of the most efficient host lattices for rare earth ions, which substitute Y3+ ions [1, 2]. Yttrium silicates doped with different metallic ions exhibit attractive luminescent properties for potential applications, such as plasma displays, laser materials and high-energy phosphors [3]. The synthesis methods frequently used to obtain Y2Si2O7 are the conventional solid-state reaction, sol-gel and hydrothermal process. The sol–gel process is based on the polycondensation of hydrolyzed alkoxides or colloidal dispersions, therefore non-substituted and substituted silicon alkoxides are used as source of Si, typically Si(OC2H5)4 (TEOS) or CH3–Si(OC2H5)3 (MTEOS). In the present work, a new method to synthesize Dy-doped yttrium disilicate (Dy0,05Y1,95Si2O7) phosphors is proposed using a combination of sol-gel and coprecipitation techniques. The gel of silica particles were obtained by surfactant-assisted sol-gel process [4], from sodium silicate solution, an unusual precursor of Si. Then yttrium and dysprosium were co-precipitated over these particles. Pure α-phase and β-phase of Y2Si2O7 were obtained after calcining the synthesized precursor at 1100°C and 1400°C respectively (Fig. 1). β-phase showed superior luminescence efficiency (Fig. 2).openAccessResumo de eventos científicos0000-0002-0967-0807https://orcid.org/0000-0002-0155-9100