Mamand Dyari M, Aziz Dara M, Khasraw Siyamand S, Al-Azzawi Ahmed G S, Al-Saeedi Sameerah I, Aziz Shujahadeen B, Hassan Jamal
Department of Physics, College of Science, University of Raparin, Ranya, Kurdistan, 46012, Iraq.
Department of Chemistry, College of Science, University of Raparin, Ranya, Kurdistan, 46012, Iraq.
Sci Rep. 2025 Sep 1;15(1):32225. doi: 10.1038/s41598-025-16778-9.
In this study, graphene oxide (GO) was synthesized via a modified low-temperature Hummer's method and incorporated into a poly (ethylene oxide) (PEO) matrix to fabricate PEO/GO nanocomposite thin films using a casting technique. This work explores how GO incorporation affects the structural and optical properties of PEO, with emphasis on its suitability for optical switching and other optoelectronic applications. The films were prepared with varying GO concentrations and characterized using XRD, UV-Vis spectroscopy, and other standard techniques. XRD confirmed successful GO incorporation by revealing intercalation-induced structural changes. Optical transmittance dropped from 88% (pure PEO) to 18% (7 wt% GO), demonstrating strong UV-blocking ability. UV-Vis analysis showed a red-shift in the absorption edge with increasing GO content, and Tauc's method indicated a reduction in the optical bandgap from 5.82 eV to 2.12 eV. Key optical constants improved significantly: the refractive index rose from 1.72 to 2.21, the absorption edge decreased from 5.63 to 2.27 eV, and the extinction coefficient increased with GO loading. Wemple-DiDomenico analysis revealed a decrease in dispersion energy (from 13 to 12.7 eV) and oscillator energy (from 6.52 to 3.29 eV). Nonlinear optical properties also improved, with third-order susceptibility increasing from 0.57 × 10⁻⁵ to 2.98 × 10⁻⁵ esu and nonlinear refractive index from 4.4 × 10⁻⁵ to 5.2 × 10⁻⁵ at 7 wt% GO. Drude model analysis showed a substantial rise in the carrier concentration-to-effective mass ratio from 1.50 × 10⁵⁴ to 11.58 × 10⁵⁴ m⁻³·kg⁻¹. These enhancements demonstrate that GO-doped PEO films are promising candidates for next-generation optical switching and optoelectronic devices.
在本研究中，通过改进的低温Hummer法合成氧化石墨烯（GO），并将其掺入聚环氧乙烷（PEO）基体中，采用流延技术制备PEO/GO纳米复合薄膜。本工作探讨了掺入GO如何影响PEO的结构和光学性能，重点关注其在光开关和其他光电器件应用方面的适用性。制备了不同GO浓度的薄膜，并使用X射线衍射（XRD）、紫外-可见光谱（UV-Vis）和其他标准技术进行表征。XRD通过揭示插层诱导的结构变化证实了GO的成功掺入。光透射率从88%（纯PEO）降至18%（7 wt% GO），表明其具有很强的紫外线阻挡能力。UV-Vis分析表明，随着GO含量的增加，吸收边发生红移，Tauc方法表明光学带隙从5.82 eV降至2.12 eV。关键光学常数显著改善：折射率从1.72升至2.21，吸收边从5.63降至2.27 eV，消光系数随GO负载量增加。Wemple-DiDomenico分析表明色散能（从13降至12.7 eV）和振子能（从6.52降至3.29 eV）降低。非线性光学性能也得到改善，在7 wt% GO时，三阶非线性极化率从0.57×10⁻⁵增至2.98×10⁻⁵ esu，非线性折射率从4.4×10⁻⁵增至5.2×10⁻⁵。德鲁德模型分析表明，载流子浓度与有效质量比从1.50×10⁵⁴大幅升至11.58×10⁵⁴ m⁻³·kg⁻¹。这些增强表明，GO掺杂的PEO薄膜是下一代光开关和光电器件的有前途的候选材料。
