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In this modern age of technology, flexible, light-weight, environment-friendly and low-cost electrodes are vastly feasible for applications in energy storage devices and disposable electronics. This study presents a comprehensive report on the morphological, dielectric, and impedance characteristics of lignocellulose (LC) fibers, PbO2, and LC/PbO2 sheets. The dielectric analysis shows that the dielectric constant depends on space charge polarization in the case of LC/PbO2 composite sheets. It can be concluded from impedance spectroscopy results that LC fibers show semiconductor-like behavior and fibers appear to consist of one type of dielectric species whose impedance behavior can be modeled by a parallel combination of a resistor and a capacitor. However, the impedance response of PbO2 consists of two types of dielectric species, which can be identified as grains and grain boundaries, both of which show a small temperature dependence. The impedance behavior of LC/PbO2 composite is different in comparison to individual LC fibers and PbO2. The presented study also reveals that impedance parameters of fabricated LC/PbO2 composites are temperature-independent, which might be due to counteracting the characteristics of LC fibers and PbO2 particles. This temperature-independence of the composite is important for their use in applications in flexible devices.

Silicon nanowires (SiNWs) with unique band structure and transport properties are considered potential candidates for future nanoelectronics devices such as field-effect transistors (FETs). We present a model of a SiNW-FET comprising $$\langle100\rangle$$ silicon atomic wires with a cylindrical-shaped metallic gate wrapped around the wires. For this purpose, we report on the energy band structure and density of states of SiNWs of diameters 5.93 A, 9.71 A and 13.55 A with $$\langle100\rangle$$ cleavage orientation by employing generalized gradient approximation and meta-generalized gradient approximation as well as the semi-empirical extended-Huckel model. Moreover, the transmission and transport properties of doped and undoped SiNWs of diameter 5.93 A with and without vacancy defects are explored using a non-equilibrium green function approach with self-consistent calculations. The corresponding I–V characteristics of the proposed cylindrical-shaped metallic-gate SiNW-FET under a specific gate voltage are presented. Our results show that the undoped SiNWs with vacancy defects on the surface are more suitable candidates for nanoelectronic device applications such as FETs in contrast to their counterparts with vacancies at the center.

Graphite-based composites are commonly used as an anode and current collector for energy storage devices; however, they have inherently limited potential for large scale rechargeable systems due to a brittle structure. In this study, flexible and light-weight graphite-based electrodes are prepared by incorporation of lignocelluloses fibers directly collected from a self-growing plant, Typha Angistifolia. Electrical properties of graphite and lignocelluloses composite sheets are enhanced by electrodeposition of gold in a three-electrode setup. Electrochemical deposition of gold on a lignocelluloses/graphite paper electrode was obtained in potentiostatic mode by the application of reduction potential −0.95 V for 2000 s, 600 s, and 100 s. The gold-deposited paper electrodes showed efficient kinetics by shifting redox peaks towards lower potentials in cyclic voltammetry measurements, whereas impedance measurements revealed seven orders of magnitude reduction in the resistive properties. Incorporated flexibility and superior electrical/electrochemical performance within presented graphite-based composites will provide cutting-edge characteristics for high-tech application of energy storage devices by keeping a focus on modern disposable technology.