Ag nanoparticles in A4 zeolite as efficient catalysts for the 4-nitrophenol reduction

Confinement of Highly Luminescent Silver Nanoclusters in FAUY Zeolite: A Study on the Formation Effects of Silver Nanoclusters and the Sensitization of Tb3+

“…The inset HRTEM image in Figure S2b displays a lattice space of 0.2291 nm for the nanoparticles in FAUY-20Ag, which is in line with the silver nanoparticle (111) facet. 36,37 To better understand the influence of the Ag + loading degree and thermal treatment temperature on the luminescence properties of Ag NCs and obtain optimized emission, the integrated emission intensities of FAUY-xAg (x = 5, 10, 20, and 30) under various thermal treatment temperatures were calculated from their respective PL spectra and are shown in Figure 3. It is clear that the integrated emission intensities of all the considered samples first increase and then decrease under 300−800 °C thermal treatments; however, the optimized temperatures show Ag + loading level dependency, which are 400 °C for FAUY-5Ag, 500 °C for FAUY-10Ag, and 600 °C for FAUY-20Ag and FAUY-30Ag.…”

“…The strong absorption band at 213 nm belongs to the 4d 10 → 4d 9 5s 1 electronic transition of the isolated Ag + located at specific sites within FAU or LTA zeolite frameworks. ,, The absorption bands at 280 and 310 nm that result in the green emission can be attributed to Ag 3 n + clusters, while the absorption band at 450 nm is due to the surface plasmon resonance of silver nanoparticles. , Figure S2 (in the Supporting Information) shows the corresponding TEM and HRTEM images, from which the silver nanoparticles with diameters larger than 3.0 nm can be observed besides those smaller ones. The inset HRTEM image in Figure S2b displays a lattice space of 0.2291 nm for the nanoparticles in FAUY-20Ag, which is in line with the silver nanoparticle (111) facet. , …”

Luminescence Control of Silver Nanoclusters by Tailoring Extra-Framework Cations in FAU-Y Zeolite: Implications for Tunable Emission

“…However, very few Ag NPs between 2 and 5 nm can be seen when carefully checking the sample surfaces, as shown by the HRTEM images in Figure f–h. The lattice space of Ag NPs is 0.2288 nm in 2LiY20Ag, 0.2281 nm in NaY20Ag, and 0.2303 nm in 2CaY20Ag, which is in accordance with the Ag NPs (111) facet. , …”

“…The lattice space of Ag NPs is 0.2288 nm in 2LiY20Ag, 0.2281 nm in NaY20Ag, and 0.2303 nm in 2CaY20Ag, which is in accordance with the Ag NPs (111) facet. 38,39 It has been generally agreed that the Ag 3 n+ clusters formatted inside D6r cages in Ag + -exchanged FAU zeolites are responsible for the green emission under UV excitation. 1,17,25 As we know, the radiative emissions of metal nanoclusters with sizes commensurate to the Fermi wavelength of electrons are due to the transitions of discrete electronic energy levels resulted from the strong quantum confinement of free electrons, and the splitting of the discrete electronic energy levels and the exciton−phonon coupling between the emitting centers and the host lattice essentially determines their luminescence property.…”

A review of the synthesis and application of zeolites from coal-based solid wastes

“…Twenty-five thousand kg of zeolite were applied to 1.0 hectare of 25 cm surface soil, and the leaching rate of most metals (Cd, Co, Cu, Ni, Zn) in the soil decreased around (95-99)wt% after two years. Terzano et al [144] added 10wt% coal fly ash to the soil, and then synthesized 5wt% and 12wt% zeolite products (mixtures of Na-X zeolite and Na-P zeolite) in situ at 30 and 60°C for six months, respectively. The synthesis of zeolite was not affected by organic matter or mineral phases.…”