Aziz Shujahadeen B, Nofal Muaffaq M, Brza Mohamad A, Hussein Sarkawt A, Mahmoud Khaled H, El-Bahy Zeinhom M, Dannoun Elham M A, Kareem Wrya O, Hussein Ahang M
Hameed Majid Advanced Polymeric Materials Research Lab, Physics Department, College of Science, University of Sulaimani, Qlyasan Street, Kurdistan Regional Government, Sulaimani 46001, Iraq.
Department of Civil Engineering, College of Engineering, Komar University of Science and Technology, Kurdistan Regional Government, Sulaimani 46001, Iraq.
Polymers (Basel). 2021 Oct 11;13(20):3484. doi: 10.3390/polym13203484.
In this research, direct band gap polymer composites with amorphous phase, which are imperative for optoelectronic devices applications were synthesized. The solution cast technique was used to produce polyethylene oxide (PEO)/calcium titanate (CaTiO) nanocomposite (NC) films. The X-ray diffraction (XRD) confirms the growth of amorphous nature within PEO with CaTiO addition. The optical band gaps of pure PEO and PEO/CaTiO NC films were calculated using analysis of ultraviolet-visible (UV-Vis) spectra. The change in absorption edge toward lower photon energy is evidence of polymer modification. The dispersion behavior of the refractive index of PEO was manipulated to a higher wavelength upon doping with CaTiO. Upon adding CaTiO to the pure PEO polymer, the dielectric constant and refractive index were considerably modified. The band gap shifts from 4.90 eV to 4.19 eV for the PEO incorporated with an optimum portion of 8 wt. % of CaTiO. The types of the electronic transition in composite samples were specified, based on the Taucs model and the optical dielectric loss. The alteration of UV/Vis absorption spectra of the NC film was considered a suitable candidate to be applied in nanotechnology-based devices. The spherulites ascribed to the crystalline phase were distinguished through the optical microscopy (OM) study.
在本研究中，合成了具有非晶相的直接带隙聚合物复合材料，这对于光电器件应用至关重要。采用溶液浇铸技术制备了聚环氧乙烷（PEO）/钛酸钙（CaTiO₃）纳米复合（NC）薄膜。X射线衍射（XRD）证实了添加CaTiO₃后PEO中非晶性质的增长。通过紫外-可见（UV-Vis）光谱分析计算了纯PEO和PEO/CaTiO₃ NC薄膜的光学带隙。吸收边向较低光子能量的变化是聚合物改性的证据。掺杂CaTiO₃后，PEO折射率的色散行为在更高波长处得到调控。向纯PEO聚合物中添加CaTiO₃后，介电常数和折射率有显著改变。当PEO中掺入8 wt.%的最佳比例CaTiO₃时，带隙从4.90 eV 变为4.19 eV。基于陶克斯模型和光学介电损耗确定了复合样品中电子跃迁的类型。NC薄膜UV/Vis吸收光谱的变化被认为是适用于基于纳米技术的器件的候选材料。通过光学显微镜（OM）研究区分了归因于结晶相的球晶。
