In the present paper, (ZnO)–(Co₃O₄) nanocomposite thin films have been prepared by using spray pyrolysis deposition on a glass substrate at 350^∘C. After that, the as-obtained films have been characterized and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the double beam UV-visible (UV-vis) spectrophotometer. Furthermore, the Bruggeman model is used to predict the evolution of the optical dielectric constant (real and imaginary parts: εr and εi) to compare them with those obtained from the experimental results. The XRD pattern reveals that the nanocomposite film has diffraction peaks 2θ=31.33∘, 36.95^∘ corresponding respectively to the (220), (311) planes of cubic Co₃O₄ and another about of 2θ=36.26∘ corresponding to the (101) plane of Wurtzite ZnO. Using the Debye Scherrer formula, the crystallite size of (ZnO)0.5–(Co₃O4)0.5 nanocomposite is found about 32nm, while the obtained thickness of this nanocomposite is about 780nm using the DekTak Stylus profilometer. Besides, the morphology analysis shows that the nanocomposite sample is well covered without holes and/or cracks and it has uniform dense grains. The evaluation of the transmittance, reflectance, refraction index, extinction coefficient, real and imaginary parts of dielectric constant as function of wavelength illustrates that the optical response of nanocomposite thin film (ZnO)0.5–(Co₃O4)0.5 depends on the influence of two mediums of pure materials ZnO and Co₃O₄ and their interaction. In addition, the direct band gap vs incident photon energy obtained from the Tauc plot equation shows that this nanocomposite has three values of band gap energy which are Eg1=1.54eV, Eg2=2.2eV (correspond to pure Co₃O₄ film) and Eg3=3.47eV (correspond to pure ZnO film). Besides, the application of the Bruggeman equation indicates that the influence of the values of volume concentration and optical dielectric constant of the ingredient nanomaterials (ZnO and Co₃O4) is significant on the value of the effective dielectric constant of nanocomposite thin film. The specific result of this study is the similarity between the spectra obtained from the Bruggeman model and the measured one, which proves that the application of this model is useful for the prediction of the optical properties of the composite.

中文翻译：

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(ZNO)-(CO3O4) 纳米复合材料的喷雾热解工艺合成与表征：Bruggeman 模型在光学性能修正中的应用

在本文中，(ZnO)-(Co ₃ O ₄ ) 纳米复合薄膜已经通过在 350 ℃下在玻璃基板上使用喷雾热解沉积制备^。之后，对所获得的薄膜进行了表征和分析 X射线衍射 (XRD)、扫描电子显微镜 (SEM) 和双光束紫外-可见 (UV-vis) 分光光度计。此外，Bruggeman 模型用于预测光学介电常数的演变（实部和虚部：εr和ε一世)将它们与从实验结果中获得的结果进行比较。XRD图谱显示纳米复合膜具有衍射峰2θ=31.33∘, 36.95 ^∘分别对应于立方 Co ₃ O ₄的(220)、(311)面和另外约2θ=36.26∘对应于纤锌矿ZnO的（101）面。使用 Debye Scherrer 公式， (ZnO) 的微晶尺寸0.5–(Co ₃ O4)0.5纳米复合材料被发现约 32nm, 而这种纳米复合材料的所得厚度约为 780nm 使用 DekTak Stylus 轮廓仪。此外，形貌分析表明，纳米复合材料样品被很好地覆盖，没有孔洞和/或裂纹，并且具有均匀致密的晶粒。透过率、反射率、折射率、消光系数、介电常数的实部和虚部作为波长的函数的评估表明纳米复合薄膜 (ZnO) 的光学响应0.5–(Co ₃ O4)0.5取决于纯材料ZnO和Co ₃ O ₄两种介质及其相互作用的影响。此外，从 Tauc 曲线方程获得的直接带隙与入射光子能量的关系表明，这种纳米复合材料具有三个带隙能量值，它们是乙G1=1.54电子伏特，乙G2=2.2eV（对应于纯Co ₃ O ₄薄膜）和乙G3=3.47eV（对应于纯 ZnO 薄膜）。_{此外，Bruggeman方程的应用表明成分纳米材料（ZnO和Co 3} O ）的体积浓度和光学介电常数值的影响4)对纳米复合薄膜的有效介电常数值有重要意义。本研究的具体结果是Bruggeman模型得到的光谱与实测光谱的相似性，证明了该模型的应用对于预测复合材料的光学性能是有用的。