Au-Ag NPs embedded Sago Starch-Sodium Alginate composites: An investigation of structural, thermal and dielectric properties for applications in flexible electronic devices

Abstract

Flexible bio-friendly nanocomposite (NC) films based on Sago Starch-Sodium Alginate (SS-SA) blend embedded with Auc-Ags core–shell nanoparticles (NPs) were synthesized via solution casting approach. The appearance of XRD peaks corresponding to Ag NPs confirms the formation of Ag shell over Au core and also evidenced by HR-TEM, SAED pattern, FE-SEM. Thermogravimetric analysis (TGA) suggests enhanced thermal stability with addition of NPs in polymer blend. Dielectric spectroscopy reveals that, dielectric permittivity (ε') of polymer matrix increases from 18.8 (at 100 Hz) to 96.2 at room temperature (for 1.5 wt% Auc-Ags@SS-SA NC), and increases to 2227.4 at 353 K. This increase is attributed to the formation of nano-capacitors. Enhanced ac conductivity, low relaxation time and decrease in grain/grain boundary resistances with the addition of Auc-Ags NPs indicate enhanced charge transport. Enhanced dielectric permittivity and low tangent loss make these NC films a potential contender for charge storage in flexible electronic devices.