Effect of 100 KeV Ar+ ion beam irradiation on ZnO thin films – Influence of morphology vis-a-vis electrode/electrolyte interface and its impact on photoelectrochemical water splitting

The present study attempts quantitative determination of changes in the morphological surface features viz. fractal dimension, lower and upper cut off length scale through Power Spectral Density analysis prior to and after irradiation of 100 KeV Ar⁺ ion beam at incidence angles of 0°, 40° and 60° on ZnO thin films. All the unirradiated and irradiated samples are subjected to photoelectrochemical characterization and a correlation between photoelectrochemical performance and morphological parameters is established. Sample irradiated at 40° angle at the fluence of 5 × 10¹⁶ ions/cm² is found to possess maximum fractal dimension of 2.72, lower and upper cut off length scale of 3.16 nm and 63.00 nm respectively. This sample exhibits maximum photocurrent density of 3.19 mA/cm² and applied bias photon-to-current efficiency of 1.12% at 1.23 V/RHE. Hydrogen gas collected for duration of 1 h for the same sample was ~4.83 mLcm^?2.     

Carbon-based TiO2-x heterostructure nanocomposites for enhanced photocatalytic degradation of dye molecules

Application of brown titanium dioxide (TiO_2-x) and its modified composite forms in the photocatalytic decomposition of organic pollutants in the environment is a promising way to provide solutions for environmental redemption. Herein, we report the synthesis of effective and stable TiO_2-x nanoparticles with g-C₃N₄, RGO, and multiwalled carbon nanotubes (CNTs) using a simple hydrothermal method. Among all the as-synthesized samples, excellent photocatalytic degradation activity was observed for RGO-TiO_2-x nanocomposite with high rate constants of 0.075 min^?1_, 0.083 min^?1 and 0.093 min^?1 for methylene blue, rhodamine-B, and rosebengal dyes under UV–Visible light irradiation, respectively. The altered bandgap (1.8 eV) and the large surface area of RGO-TiO_2-x nanocomposite impacts on both absorption of visible light and efficiency of photogenerated charge electron (e^?)/hole (h⁺) pair separation. This resulted in enhanced photocatalytic property of carbon-based TiO_2-x nanocomposites. A systematic study on the influence of different carbon nanostructures on the photocatalytic activity of brown TiO_2-x is carried out.     

Brain tumor detection and segmentation using mesh-free super-diffusive model

Multimedia Tools and Applications - Brain tumor detection and segmentation is a complex and challenging task in image processing. Most of the techniques used for brain tumor detection and...     

Effect of MQL and nanofluid on the machinability aspects of hardened alloy steel

Abstract

The current research comprises of various machinability aspects of 4340 hardened alloy steel which are scrutinized with in context of improvements in main cutting force, tool flank wear, crater wear, surface roughness, micro-hardness, machined surface morphology, chip morphology, chip reduction coefficient and apparent coefficient of friction under three different cutting fluid applications i.e. compressed air, water soluble coolant and nanofluid (using eco-friendly radiator coolant as the base fluid and Al₂O₃ as the nanoparticle) using uncoated cermet cutting inserts and a comparative assessment was performed to select which fluid performed better in terms of various machining attributes among three cutting fluids. The minimum quantity lubrication technique (MQL) was used in which a smaller volume of coolant sprinkled at high pressure. This method is found as the most effective alternative to minimize health risks and machining costs, which is quite high in other setups. The test specimen was machined at three different cutting speeds i.e. 100, 120 and 140?m/min along with two machining parameters i.e. feed and depth of cut were kept constant respectively at 0.2?mm/rev and 0.4?mm. Outcomes made a conclusion that Al₂O₃ enriched ecofriendly nanocoolant outperformed both compressed air and water soluble coolant in terms of every machinability aspects.     

Hot Electron Relaxation in Ferromagnetic Metals: Memory Function Approach

Journal of Superconductivity and Novel Magnetism - This study leads to the investigation of the non-equilibrium electron relaxation in ferromagnetic metals. Here we consider the relaxation of...     

Bi2MoO6 hierarchical microflowers for electrochemical oxygen evolution reaction

Solvothermal Bi₂MoO₆ hierarchical microflowers synthesis has been successfully attempted. Methanol, ethanol and isopropanol have been mediated to synthesize three kinds of Bi₂MoO₆ hierarchical microflowers. Highly oriented (311) plane growth of orthorhombic Bi₂MoO₆ hierarchical microflowers have been confirmed. Interstitial vacancies and its role on electrochemical activity have been extensively discussed. Electrode fabrication was constructively done by using Ni foam substrate. Half cell arrangement of each electrode in alkaline medium has been designed to measure the electrochemical activity towards water oxidation. High current density of 356 mA/cm² was afforded by Bi₂MoO₆ hierarchical microflowers mediated by ethanol solvent during synthesis. Low Tafel slope value of 43 mV/dec has been reported to obtain 10 mA/cm² current density. Higher conductivity long with very good electron transportation has been achieved and is also adapted for 12 h long time stability test and achieved 86% of retention in its performance. Hence, optimally prepared Bi₂MoO₆ hierarchical microflowers could be an efficient electrode for clean energy fabrication.