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Supercapacitors (SCs) are a kind of energy storage that replaces conventional batteries and capacitors. Compared to capacitors, they can store more energy and supply power at a faster rate. Co3O4 nanoparticles have been employed in various products, including rechargeable Li-ion batteries, solar cells, supercapacitors, field effect transistors, field emission materials, magneto-resistive devices, capacitors, and gas sensors. Cobalt is valuable in various undertakings because, as early research found, it may reveal irregular oxidation forms (Co2+, Co3+, and Co4+). Because cobalt has a dual nature, its oxide structures can contain three distinct twist forms: inferior, intermediate, and superior. Co3O4 nanoparticles were created in the current study utilizing the sol-gel technique. Co3O4 nanoparticles with a cubic phase and a spinel structure underwent a two-hour thermal treatment at 600 °C in a furnace. The exceedingly pure cubic crystalline phases are visible using XRD. The crystallite size is 47 nm. Optical parameters were discovered via FTIR and U-V Visible spectroscopy with an energy band gap of 3.67 eV. The FESEM and EDX were also used to compute the surface morphology and elemental mapping of Co3O4. Additionally, Co3O4 electrochemical characteristics as determined by cyclic voltammetry (CV) with a specific capacitance of 532 F/g, galvanostatic charge-discharge with a specific capacitance of 614.2 F/g, and EIS confirmed the capacitive behavior of the Co3O4, which displayed a straight line at low frequencies and a very brief kinetic arc at high frequencies. [ABSTRACT FROM AUTHOR]

The paper discusses the critical importance of surface roughness measurement in CNC milling processes, particularly when working with Al- 6061 alloy. It highlights the challenges being faced by existing methodologies while assessing surface roughness accurately and it also emphasizes the need for a more systematic approach. Leveraging the Taguchi Method, the study aims to optimize surface roughness measurement parameters to improve machining outcomes. The novelty of the research lies in its application of the Taguchi Method to develop a projecting model specifically for optimizing roughness of surface of Al-6061 alloy in CNC Milling. By analyzing the factors influencing surface roughness and their interactions, the study aims to provide insights that can enhance machining accuracy and efficiency. The anticipated benefits of this research to the machining community include offering a more efficient and accurate approach to surface roughness measurement, thereby improving machining quality and productivity. The paper serves as a valuable reference for researchers and practitioners looking to enhance their understanding and practices in the context of Al-6061 alloy machining. It’s noted that several factors, such as speed of the spindle,Cutting depth, cutting depth, geometry of the tool, and material stuffs, influence the final roughness of surface. In this Taguchi Method that implemented to address the challenge of finding optimized conditions for the best surface finish by identifying the optimal grouping of variable parameters.Overall, the paper presents a promising methodology to improving roughness of surface measurement in the CNC milling processes, particularly for Al-6061 alloy, and offers potential insights that could benefit the machining industry.Aluminum is one of the most widely used metals in the construction of airplanes, trucks, spaceships etc. where high strength and light weight are required. Aluminum is used here for the observation.

The study herein is directed toward the tuning of various properties of recyclable and biocompatible polymer: chitosan (CS) via incorporating the variable wt% of r‐GO in the polymer. The CS/r‐GO polymer nanocomposites (PNCs) are prepared in the form of free‐standing film by solution mixing and casting technique. To search the potential applications, the prepared PNCs are characterized in terms of structural, photoluminescence (PL), surface morphology, optical, and Raman spectra. The crystalline size and microstrain both are enhanced with rise in wt% of r‐GO nanofiller. Raman spectra confirm that as the wt% of r‐GO increases, there is a minor shift toward a smaller wavenumber in the locations of the D, G, and 2D bands, while the intensity ratios (ID/IG$\left(\right. I_{\text{D}} / I_{\text{G}}$) increase. Field‐emission scanning electron microscopy results are capable of offering details regarding the surface quality for the interface purposes. The characteristic peaks and their broadening in PL spectra, chromaticity coordinates, dominant wavelength, and correlated color temperature are altered with variation of r‐GO wt.%. The optical bandgap, refractive index, and Urbach energy are found to tune with varying the nanofiller wt.%. These results suggest that CS/r‐GO PNC may be the potential candidate for possible application in fabricating the tunable optoelectronic devices. [ABSTRACT FROM AUTHOR]

Motivated from the extraordinary properties of CeO2 nanomaterial, this article is directed toward the synthesis of recyclable polyvinyl alcohol–CeO2 polymer nanocomposite with variable wt% of CeO2 and investigating their improvements in structural, electrical, optical, and surface properties. The crystalline size and micro‐strain are measured using X‐ray diffraction (XRD) data. Ultraviolet–visible–near‐infrared spectrophotometer is used to study the optical characteristics. Absorbance with redshift is found to enhance; while optical bandgap is reduced from 2.51 to 2.36 eV on increasing wt% of CeO2 nanofiller. The mechanism of reduction in bandgap is supported by the XRD analysis. Refractive index is found to vary from 2.54 to 2.59 and the range of Urbach energy varies from 1.19 to 0.42 eV on increasing the amount of nanofillers. Surface morphology, dielectric constant, and electrical conductivity are also found to improve with increasing wt% of nanofiller. The dielectric constant is improved from 60 to 120 at 1.5 Hz. The rise in conductivity with increasing wt% of CeO2 and rising frequency is due to the enhancement of mobility of the charge carriers and ionic hopping mechanism in conduction process. Characterization outcomes suggest that the prepared composites can be claimed as useful in fabricating the flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

This article reports the synthesis of NiFe2O4 nano-ferrites in form of nanoparticles and investigating their various properties such as structural, surface morphology, electrocehmical and electrical properties with the help of a variety of characterization techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), cyclic-voltammetry, and impedance analyzer. The NiFe2O4 nanoparticles were synthesized via sol–gel route for the suitable application in making the energy storage devices like supercapacitors. Structural analysis was performed by XRD for determining the crystalline size and micro-strain produced in the sample via study of W–H plot. The average crystalline size was found ~ 40 nm and the micro-strain was determined as ~ (− 0.00346) corresponding to negative intercept in W–H plot. The negative micro-strain confirms the presence of compressive micro-strain in the sample. The FESEM was used for analysis of surface morphology which confirms the size of nanoparticles. For understanding the super-capacitive behavior of the synthesized samples, recording of cyclic-voltammetry data for the prepared sample was performed at the scan frequency 10, 20, 50, and 100 mV/s. The maximum area is covered at the 100 mV/s scan rate with maximum specific capacitance of ~ 200 F/g. The highest contribution of active ions is seen at lower scan rates during the redox reaction and vice versa. For electrical characteristics (dielectric constant, dielectric loss, ac conductivity, and impedance), the impedance analyzer was utilized. These all studies suggest that the nano-ferrites like NiFe2O4 nano-particles are very important materials which show low loss at very high frequency and thus these materials can be recommended for high frequency supercapacitor applications. [ABSTRACT FROM AUTHOR]

In the early studies, thorough calculations for the band structures of binary and ternary semiconductor compounds have been performed. But in those studies the role of substrate, on which the studied compound is grown, has not been accounted. In this paper, the calculations for the band structures of technologically important binary semiconductors i.e. GaAs and InAs considering the effect of substrate have been performed and the results have been analysed successfully. In results, it has been shown that considering the lattice matched substrate with the grown semiconductor layers is very important for better device performance. [ABSTRACT FROM AUTHOR]