Bioinspired GO/Au nanocomposite synthesis: Characteristics and use as a high-performance dielectric material in nanoelectronics
Ahmad Khalilullah, Kaifee Sayeed, Imran Uddin
Abstract
A bioinspired method was used to synthesise graphene oxide (GO) based noble metal (Au) nanocomposite (GO/Au nanocomposite) using chemical exfoliated graphene oxide as the base matrix and biosynthesised gold (Au) nanoparticles. The morphological characterization of GO and the GO/Au nanocomposite was determined using TEM and SEM analysis. The amount of Au nanoparticles conjugated with GO was determined using an EDAX analysis. The absorption and emission properties of GO and GO/Au nanocomposite are revealed through optical studies. FTIR analysis revealed the presence of different functional groups in GO and GO/Au nanocomposite, while XRD analysis confirmed the formation of crystalline GO and GO/Au nanocomposite of different sizes. TGA analysis was used to determine the degradation behaviour of the two products with respect to temperature. An LCR analysis was used to characterise the electrical characteristics of GO dielectric features as a function of frequency between 1 Hz and 1 MHz. The dielectric permittivity and electrical conductivity of GO were very frequency-driven. The results demonstrated that GO has direct current and correlated barrier hopping conductivity processes in the low and high frequency bands. The dielectric constant and loss factors of the GO/Au nanocomposite show that the bioinspired approach includes organic macromolecules capable of modest GO reduction and so modifying the C/O ratio, resulting in an enhancement in the matrix's dielectric characteristics. This study further demonstrates that high-performance electronic devices, as well as electrical and energy storage systems based on high dielectrics, might be scaled using GO-based materials.