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Micron thin films and microsupercapacitors based on polyvinyl alcohol, starch, methyl cellulose, and nickel acetate have been fabricated using the one-step formation of laser-induced graphene. Surface finishing of films and decomposition of nickel acetate to nickel oxide have been achieved with the help of CO2 laser. The optical studies of thin films and microsupercapacitors have been conducted, which are highly transparent in the UV–visible regime. There is no need of binders, current collectors, or separators in interdigitated microsupercapacitors. Starch-based microsupercapacitors (PSM) have superior electrochemical performance and stability than methyl cellulose (PMM) in the presence of 6-M KOH electrolyte. The maximum capacitance of PSM is 28.89 µF cm−2 in 6-M KOH at the scan rate of 1 mV s−1 from cyclic voltammetry. The specific energy density is 93.75 × 10−6 µWh cm−2 and the power density is 0.12 µW cm−2. The PMM has a specific capacitance of 2.5 nF cm−2 when compared to PSM of 0.52 µF cm−2 without electrolyte. The cycle life of PSM is 2500 cycles which shows its robustness. The performance of the microsupercapacitors is better than the other gate dielectric materials used in transistors and in the range for integration of energy storage devices in on-chip electronic and photonic devices. [ABSTRACT FROM AUTHOR]

Copper-based ternary metal oxide (i.e., Cu0.52Al0.01Fe0.47O4) impregnated reduced graphene oxide nanohybrid is verified for microbial and arsenic treatment. Growth inhibition of colonies are observed around 99.99% (E. coli), and 99.83% (S. aureus) at 10–20 μg/mL of hybrid dosage, respectively. The inhibition rates for both the colonies are increased to 99.9998% at 80 μg/mL. TEM images have shown insight of cell-content/lipid leakage behavior after inoculating with the hybrid. The efficient hindrance towards microbial colony growth is attributed to better charge transfer, reactive oxygen species generation, and metal-ion release. Maximum arsenic sorption capacities are observed around 248 and 314 mg/g for As(III), and As(V), respectively (Ci ~ 500 ppm). Surface morphology studies onto arsenic adsorption are reported with atomic force microscope, and FT-IR/Raman analysis. A detailed discussion onto individual spectra of As 3d spectra confirmed the occurrence of redox transformation in arsenic species [As(III)]. The variation in the quantity (at. %) of oxygen functional groups in O1s spectra (i.e., M–O, M-OH, and -OH2) onto the hybrid supported the ligand-exchange behavior. Cyclic voltammetry study in arsenic electrolytes (10 µM – 1 mM) provides the occurrence of various in-situ electrochemical reactions supporting the redox activity. A significant electromagnetic wave absorption characteristics of the present hybrid is proposed with plausible airborne antimicrobial-agent abilities. [ABSTRACT FROM AUTHOR]

The presented study stresses that the deposition temperature is an important parameter to determine the quality and properties of deposited Cu2O thin films on copper (Cu) and fluorine-doped tin oxide (FTO) substrates. The optical and electrical properties of chemical bath deposited (CBD) cuprous oxide (Cu2O) thin films with a variety of deposition temperatures (50, 60, 70, and 80 °C) have been extensively investigated. The X-ray diffraction studies reveal the cubic polycrystalline structure of deposited thin films. The scanning electron microscopy (SEM) exhibits a homogeneous thin film constituting Cu2O crystals for 60 °C. Optical studies show the least energy bandgap of 1.90 eV at the optimized deposition temperature. The Cu deposited Cu2O thin film possesses very little resistivity and higher charge carrier concentration mainly due to the contribution from the conducting Cu substrate. The Cu2O films exhibit p-type conductivity in addition to comparable Hall mobility and improved charge carrier concentration by two orders of magnitude in the case of FTO substrate (~ 1017 cm−3). The I–V characteristics of fabricated Schottky junction with the prepared optimized thin film is presented. This study establishes 60 °C as the optimum temperature for Cu2O thin film deposition on different substrates. [ABSTRACT FROM AUTHOR]

In this work, the dielectric properties of epoxy-based composites are significantly improved with the help of the silicon carbide (SiC) filler at an operating frequency of 2.45 GHz to make them ideal candidates for microwave curing. The improvement is due to enhancement of the interfacial polarization because of the presence of the SiC filler. The dielectric properties are measured using the microwave cavity perturbation method. The cavity structure is simulated using the COMSOL@Multiphysics software to verify the measured data in terms of the resonant frequency. Finally, all the SiC-based composites including the neat epoxy resin are heated in the 2.45 GHz microwave oven at 300 W for 20 min. The thermal and mechanical properties of all the cured composites are measured, and the data are compared with their room temperature pre-cured counterparts. The dielectric properties of composite samples using SiC as a reinforcing agent in the epoxy are found to be substantially improved compared with those of the pure epoxy sample, which actually leads to better curing of these composite using the 2.45 GHz microwave system. [ABSTRACT FROM AUTHOR]