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Graphene (G) and conductive polymers have remarkable mechanical and electrical properties, but its hydrophobicity is a shortcoming in applications including environmentally friendly applications. Amyloid (Silk) fibrils are naturally occurring protein aggregates that have exceptionally strong supramolecular structures, and stable in solution which can be used as bio-nanocomposite energy storage application. Supercritical fluid approach was used to prepare the MoS2/Silk G composite structure utilising two dimensional (2D) MoS2 Sheets as a template. We have fabricated a symmetric supercapacitor device using two identical Silk G/MoS2/PDOT (poly(3,4-ethylenedioxythiophene) electrodes for practical application. Morphology, phase, and chemical composition are thoroughly investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. Furthermore, the electrochemical performance of the synthesized electrode materials is cautiously investigated using cyclic voltammetry (CV), galvanostatic charge discharge (GCD), and electrochemical impedance spectroscopic (EIS) measurements. Cyclic stability of the MoS2, Silk G/MoS2 and Silk G/MoS2/PDOT has been investigated by performing charge-discharge measurements for 1000 cycles. It is observed that the Silk G/MoS2/PDOT exhibits maximum retention of 88.5% after 1000 cycles in comparison to the pristine MoS2 (72.5%), and Silk G/MoS2 (82.1%). Nyquist plots of the MoS2, Silk G/MoS2 and Silk G/MoS2/PDOT are measured and the Silk G/MoS2/PDOT exhibited minimum charge transfer resistance which leads to the highest electrochemical performances. The symmetric supercapacitor device utilizing two identical electrodes of Silk G/MoS2/PDOT have been fabricated and it is observed that the Silk G/MoS2/PDOT exhibited maximum retention of 94.1% after 5000 charge/discharge cycles at the current density of 10 A g−l. The device exhibited an energy density of 45.53 Wh/kg at a power density of 0.168 W/kg. [ABSTRACT FROM AUTHOR]

The purpose of the present work is to investigate the microstructure and dry sliding wear behavior of hypereutectic Al-15Si- 4Cu cast alloys with grain refinement, modification and/or refinement. Pin-On-Disc wear tests were conducted under dry sliding conditions on the hypereutectic Al-15Si-4Cu cast alloy after various melt treatments for varying loads ranging from 20N to 100N with constant sliding speed of 1 m/s and for a constant sliding distance of 1000m. Tests were also conducted on the hypereutectic Al-15Si-4Cu cast alloy for sliding distance of 2000m with constant sliding speed of 1 m/s and at a normal load of 60N. Results indicate that the addition of grain refiner (Al-1Ti-3B), modifier (Sr) and refiner (P) to the hypereutectic Al-15Si-4Cu unmodified cast alloy converts large a-Al grains in to fine equiaxed a -Al grains and forms fine fibrous silicon particles and fine CuAl2 particles in the interdendritic region. This improves the wear properties of the cast alloy. [ABSTRACT FROM AUTHOR]