In this work, Silicon oxide (SiO2) nanoparticles, graphene oxide nanosheet (GO) and GO–SiO2 nanohybrid composites have been synthesized. The role of GO concentration in the starting solution was investigated and correlated to the morphological, structural and optical properties of the studied samples. The structural studies for nanohybrid composites showed that by increasing GO:weight ratio from 0.5 to 2.0, not only does the SiO2 crystalline phase change from cubic to orthorhombic, but the structure of GO also transformed to RGO. The related FESEM images indicate that GO sheets are well-covered by SiO2 nanoparticles with very small grain size and that the accumulation of nanoparticles on each sheet has a high density. Linear Optical measurements showed two optical band gaps of [Formula: see text][Formula: see text]eV and 5.3[Formula: see text]eV for SiO2 nanoparticles, and band gap value of 4.15[Formula: see text]eV for GO nanosheets, which it reduces to 3.3[Formula: see text]eV after formation of the nanohybrid composite with GO: SiO2 weight ratio of 2.0. The nonlinear optical properties of GO–SiO2 with different weight ratio are measured using Z-scan technique. The results showed that the nonlinear refractive index of SiO2 and GO nanoparticles and nanohybrid composite (0.5:1,1:1,2:1) ([Formula: see text]–[Formula: see text]) changed and has a negative sign. It was observed that the nonlinear refractive index changes in different ratios of compounds. Experimental results show that after the formation of the composite, the nonlinear refractive index shows a significant increase in the presence and effectiveness of the GO.

中文翻译：

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氧化石墨烯-氧化硅纳米杂化复合材料的非线性光学折射率表征

在这项工作中，氧化硅（SiO2) 纳米颗粒、氧化石墨烯纳米片 (GO) 和 GO-SiO2已经合成了纳米杂化复合材料。研究了起始溶液中 GO 浓度的作用，并将其与所研究样品的形态、结构和光学性质相关联。纳米杂化复合材料的结构研究表明，通过将 GO：重量比从 0.5 增加到 2.0，不仅2晶相从立方转变为正交，但 GO 的结构也转变为 RGO。相关的 FESEM 图像表明 GO 片材被 SiO2 很好地覆盖2颗粒尺寸非常小的纳米颗粒，并且每个薄片上的纳米颗粒的积累具有高密度。线性光学测量显示 [公式：见文本][公式：见文本]eV 和 5.3 [公式：见文本]eV 的 SiO 的两个光学带隙2GO 纳米片的带隙值为 4.15[公式：见文本]eV，在与 GO：SiO形成纳米杂化复合材料后，带隙值降至 3.3[公式：见文本]eV2重量比为 2.0。GO-SiO的非线性光学性质2使用Z扫描技术测量不同重量比。结果表明，SiO的非线性折射率2和 GO 纳米颗粒和纳米杂化复合材料 (0.5:1,1:1,2:1) ([公式: 见正文]-[公式: 见正文]) 发生变化并带有负号。观察到非线性折射率随化合物的不同比例而变化。实验结果表明，复合材料形成后，非线性折射率显示出GO的存在和有效性显着增加。