Mahmud Eashika, Mollik Shafiqul I, Islam Muhammad Rakibul
Department of Physics, Bangladesh University of Engineering and Technology (BUET), Dhaka, Bangladesh.
PLoS One. 2024 Dec 30;19(12):e0309469. doi: 10.1371/journal.pone.0309469. eCollection 2024.
High dielectric constants with less dielectric loss composites is highly demandable for technological advancements across various fields, including energy storage, sensing, and telecommunications. Their significance lies in their ability to enhance the performance and efficiency of a wide range of devices and systems. In this work, the dielectric performance of graphene oxide (GO) reinforced plasticized starch (PS) nanocomposites (PS/GO) for different concentrations of GO nanofiller was studied. The surface morphology, and chemical and structural properties of the PS/GO nanocomposites were investigated by field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectrometry (FTIR), and X-ray diffractometer (XRD). The FESEM study showed a uniform dispersion of the GO nanofiller in the nanocomposites. The XRD analysis showed a reduction in d-space due to the incorporation of GO nanofiller in the nanocomposites. The FTIR data exhibits the formation of hydrogen bonds among PS and GO nanofillers, suggesting the presence of strong interaction between them. The dielectric properties of the nanocomposites were studied at room temperature in the frequency range 100 Hz‒1 MHz. The dielectric constant was found to improve due to the incorporation of GO. This composite nanomaterial also provides low dielectric loss at low frequency. Moreover, an increasing trend is observed for the AC conductivity of the composites. From the complex impedance study, the changes in various impedances with low to high-frequency ranges have been calculated and explained in the equivalent circuit diagram. The complex impedance spectra analysis shows the change in resistance and constant phase element (CPE): grain boundary resistance, R2 decreases from 4.3 KΩ to 1.9 KΩ, and CPE increases from 0.59 μF to 0.72 μF for PS/GO (0.5%) nanocomposite. This study will provide a potential route for the fabrication of biocompatible dielectric device fabrication.
具有低介电损耗的高介电常数复合材料在包括能量存储、传感和电信在内的各个领域的技术进步中具有很高的需求。它们的重要性在于能够提高各种设备和系统的性能和效率。在这项工作中，研究了不同浓度氧化石墨烯（GO）纳米填料增强的增塑淀粉（PS）纳米复合材料（PS/GO）的介电性能。通过场发射扫描电子显微镜（FESEM）、傅里叶变换红外光谱（FTIR）和X射线衍射仪（XRD）研究了PS/GO纳米复合材料的表面形态、化学和结构性质。FESEM研究表明GO纳米填料在纳米复合材料中均匀分散。XRD分析表明，由于在纳米复合材料中加入了GO纳米填料，d间距减小。FTIR数据显示PS和GO纳米填料之间形成了氢键，表明它们之间存在强相互作用。在室温下，在100 Hz至1 MHz的频率范围内研究了纳米复合材料的介电性能。发现由于加入GO，介电常数有所提高。这种复合纳米材料在低频下也具有低介电损耗。此外，观察到复合材料的交流电导率呈上升趋势。通过复阻抗研究，计算了不同阻抗在低到高频范围内的变化，并在等效电路图中进行了解释。复阻抗谱分析显示了电阻和恒相位元件（CPE）的变化：对于PS/GO（0.5%）纳米复合材料，晶界电阻R2从4.3 KΩ降至1.9 KΩ，CPE从0.59 μF增至0.72 μF。这项研究将为制造生物相容性介电器件提供一条潜在途径。
