Photoluminescence enhancement of Eu³⁺ ions by Ag species in SiO₂ three-dimensionally ordered macroporous materials

Abstract

The existing states of silver depend on the sintering temperature of SiO 2 three-dimensionally ordered macroporous (3DOM) materials. Several species related to silver (Ag + ions, Ag + -Ag + and Ag nanoparticles) were demonstrated in SiO 2 3DOM materials prepared at 550 1C. Only Ag nanoparticles were observed in SiO 2 3DOM materials prepared at 750 1C. The influence of silver species on the photoluminescence properties of Eu 3+ was investigated systematically in SiO 2 3DOM materials. The results show that photoluminescence enhancement of Eu 3+ ions was induced by Ag species in SiO 2 3DOM materials. For the SiO 2 3DOM materials prepared at 550 1C, the enhancement of Eu 3+ luminescence is attributed to energy transfer from Ag + -Ag + to Eu 3+ under excitation at 345 or 280 nm, while the luminescence enhancement of Eu 3+ is due to energy transfer from isolated Ag + to Eu 3+ under excitation at 245 nm. For the SiO 2 3DOM materials prepared at 750 1C, the luminescence of Eu 3+ was enhanced due to the plasmon resonance effect of Ag nanoparticles.

White luminescence from sol–gel silica doped with silver

“…One of these was in the ultraviolet region centred at 3.26 eV (380 nm), while the second, much larger, additional peak dominating the broadening process was centred at 2.25 eV (550 nm). Although these two additional peaks in the Ag-doped sample correspond remarkably well with the emission wavelengths given earlier by Lai et al [24] for Ag ? ions (396 nm) and Ag ?…”

“…ion pairs near 540 nm. In their study of macroporous sol-gel silica, Lai et al [24] found that the excitation peak corresponding to Ag ? -Ag ?…”

“…pairs, respectively, and excited effectively at about 350 nm). Lai et al [24] have recently considered the enhancement of Eu 3? luminescence due to Ag species in macroporous sol-gel silica and provide a simplified energy structure diagram indicating the emission from Ag ?…”

Preparation and photoluminescence enhancement of Au nanoparticles embedded LaPO4:Eu3+ inverse opals

“…The SiO 2 sol including chloroauric acid or AgNO 3 was infiltrated into the opal templates. After the sintering, the Au or Ag nanoparticles were formed in the interior of nano‐sized wall of amorphous SiO 2 inverse opal and the Au or Ag nanoparticles embedded SiO 2 inverse opal was obtained . The formation of metal nanoparticles in the interior of nano‐sized wall of inverse opal comprised of crystalline host is more difficult than the preparation of pure inverse opals.…”

“…The lanthanum phosphate with the good visible light transmission is advantage for the rare‐earth doping, which is widely used in many luminescent devices. In addition, in comparison with the Ag, the Au has the good structural and chemical stability . Therefore, in this work, the Au nanoparticles with the 10‐20 nm were firstly prepared in the interior of nano‐sized wall of LaPO 4 :Eu 3+ inverse opal by the one‐step approach and the Au nanoparticles embedded LaPO 4 :Eu 3+ inverse opals were obtained.…”