Solid‐State Sintering of Glasses with Optical Nonlinearity from Mesoporous Powders

Abstract

Silica glasses dispersed with Pt nanoparticles and Ag nanoparticles are derived from solid‐state sintering of mesoporous silica SBA‐15 encapsulated with Pt nanoparticles and Ag nanoparticles, respectively. Using mesoporous powders for sintering is a facile method to lower synthesis temperature for glass making and to efficiently disperse noble metal nanoparticles in silica glass matrix. The included nanoparticles still play their functional roles in impacting on optical properties of the glass products prepared by this novel method. The glass dispersed with Pt nanoparticles exhibits brown color due to the interband electron transition of Pt nanoparticles. The coloring effect of surface plasmon resonance absorption from Ag nanoparticles colors the glass dispersed with Ag nanoparticles with yellow. Open‐aperture and closed‐aperture Z‐scan methods are applied to measure third‐order nonlinear absorption and refraction coefficient of the composite glasses, respectively, under femtosecond laser radiation at 880 nm wavelength. The glass dispersed with Pt nanoparticles behaves intense nonlinear absorption comparing with nonlinear refraction in magnitude, which could be attributed to interband electron transition by monophoton absorption of Pt nanoparticles. The glass dispersed with Ag nanoparticles shows stronger nonlinear refraction than saturated absorption. The dominant contribution to third‐order optical nonlinearity of silica glass dispersed with Ag nanoparticles is intraband transition of free electrons near the Fermi surface of Ag nanoparticles. This method may have potential applications for fabricating silica glasses dispersed with ultrafine functional particles, which are potentially applicative in the fields of photonics.

Study of Tunable Plasmonic, Photoluminscence, and Nonlinear Optical Behavior of Ag Nanoclusters Embedded in a Glass Matrix for Multifunctional Applications

“…The nonlinear refraction coefficient n 2 values were deduced by fitting the closed aperture curves using the standard equation and the n 2 values obtained were 2 × 10 −12 , 6 × 10 −12 , and 0.8 × 10 −12 cm 2 W −1 for the samples annealed at the different temperatures of 550, 600, and 650 °C, respectively. It is clearly observed from the results that the annealing temperature influenced the electronic configuration of the system . The annealed samples demonstrated large third order nonlinearities even at low excitation intensities.…”

Large‐sized La2O3‐TiO2 high refractive glasses with low SiO2 fraction by hot‐press sintering

“…The transmittance of this specimen reached 54% at 800 nm and the maximum value of 72% in the range of 3.5‐4.5 μm. Compared with the theoretical transmittance, the optical loss should be attributed to the light scattering caused by residual pores, minor translucent, and opaque microspheres . And these results suggest that silicon dioxide as a sintering agent is effective to obtain more transparent noncrystalline materials during the densification process.…”

Research Progress on Silicon-based Luminescent Glass and Preparation Techniques

“…Schematic of collapse of mesoporous structure and transformation to glass under combination of temperature and pressure(d) [40] 无 机 材 料 学 报 第 31 卷 图 9 制备含 Au 纳米晶玻璃的过程示意图 [68] Fig. 9 Schematic illustration of preparation for silica glass incorporated with Au NPs [68] 图 10 (a)掺杂 Ag 纳米颗粒的 SBA-15 粉体的 TEM 图片， (b)Ag 纳米颗粒的 HRTEM 图片, (c)烧结样品的 TEM 图片, (d)(c)图中黑点的 EDX 图谱 [69] Fig. 10 (a) TEM image of Ag NPs/SBA-15 and (b) HRTEM image of single Ag nanoparticle from (a); (c) TEM image of the sintered sample and (d) EDX spectrum taken on the dark spherical spots in (c) [69] 于颗粒大小与分布影响较小, 能够较好地保留纳米 颗粒原有的特性。 SPS 由于快速升降温速度和可以加 载压力等特点, 实现低温快速烧结, 能够有效避免 纳米材料的团聚、分解和挥发等问题, 最大限度地保 持纳米颗粒的晶粒尺寸和分布, 为可控制备掺杂纳 米材料发光玻璃建立坚实的基础, 实现具有预期发 光性能的发光玻璃。近来本课题利用该方法在制备 掺杂单一组分纳米颗粒、金属离子、量子点及荧光 粉发光玻璃方面均取得了一定的进展 [41][42]70…”