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Tuning the surface electronic properties of 2D transition metal dichalcogenides such as Molebdenum disulfide (MoS2) nanosheets is worth exploring for their potential applications in strain sensitive flexible electronic devices. Here in, the correlation between tensile strain developed in MoS2 nanosheets during swift heavy ion irradiation and corresponding modifications in their surface electronic properties is investigated. With prior structural characterization by transmission electron microscopy, chemically exfoliated MoS2 nanosheets were exposed to 100 MeV Ag ion irradiation at varying fluence for creation of controlled defects. The presence of defect induced systematic tensile strain was verified by Raman spectroscopy and X-ray Diffraction analysis. The effect of ion irradiation on in–plane mode is observed to be significantly higher than that on out-of-plane mode. The contribution of irradiation induced in-plane strain on modification of the surface electronic properties of nanosheets was analyzed by work function measurement using scanning Kelvin probe microscopy. The work function value is observed to be linearly proportional to tensile strain along the basal plane indicating a systematic shifting of Fermi surface with fluence towards the valence band.

This article investigates the surface modification of three different types of metal matrix composites (MMCs) 65vol%SiC/A356.2, 10vol% SiC-5vol% quartz/Al, and 30vol%SiC/A359 using powder-mixed electrical discharge machining (PMEDM) process. Microhardness and surface integrity were evaluated after each trial, and contributing process parameters were identified. It was found that microhardness increased primarily with increase in the density of reinforced particles in the matrix. Each workpiece was examined by X-ray diffraction (XRD) followed by scanning electron microscope (SEM) for surface integrity and material deposition. The results show the significant amount of metal transfer from the copper electrode as compared to graphite.

A novel gas sensing platform involving a hybrid of reduced graphene oxide (rGO) sheets with unsubstituted copper phthalocyanine (CuPc) nanoflowers has been explored as a room temperature ppb level chemiresistive chlorine (Cl2) sensor with a detection limit as low as 1.97 ppb.

ABSTRACT:The present work has the objective of fabricating graphene oxide (GO) and amine-functionalized graphene oxide (F-GO) reinforced epoxy composites using the casting method. Epoxy resin was dispersed separately with GO (0.5 wt%) and F-GO (0.5 and 1 wt%), and then the epoxy resin mixture cured with triethylenetetraamine at room temperature. The synthesized GO and F-GO were characterized by FT-IR and Raman spectroscopy. The interfacial interaction of Si in the composite was studied by XPS. The formation of GO and F-GO was confirmed by XRD. The tensile and flexural strength composites were measured using the UTM. The thermal behavior and dynamic mechanical behavior were examined by TGA and DMA. The surface morphology and dielectrical properties were analyzed by SEM, TEM, and impedance analyses. The results obtained from epoxy/F-GO (0.5 wt%) composite revealed higher mechanical and thermal properties than neat epoxy and epoxy/GO composites.

Cancer mortality is increasing at an alarming rate across the globe. Albeit, many therapeutics are available commercially, they are not effective and have no cure up to today. Moreover, the knowledge gap in cancer therapy persists, representing a potential blind spot for the innovation of effective anticancer therapeutics. This review presents an update on current advancements in nanopeptide therapeutics. Herein, a detailed exploration of peptide-functionalized nanoparticles for the development of nanotherapeutics was carried out. Different approaches that include self-assembly nanostructures, solid phase peptide synthesis, ligand exchange, chemical reduction, and conjugation methods for assembling peptides for functionalizing nanodrugs are also highlighted. An outlook on biomedical applications is also reviewed. Additionally, a comprehensive discussion on targeted cancer cell therapy and mechanism of action are provided. The present review reflects the functional novelty of nanodrugs to improve stability, accessibility, bioavailability, and specificity toward cancerous cells. Finally, it summarizes the current challenges and future perspectives on the formulation of these nanodrugs.

In this work, the effect of surface oxidation of molybdenum disulfide (MoS2) nanosheets induced by hydrogen peroxide (H2O2) on the work function and bandgap of MoS2 has been investigated for tuning its optical and electronic properties. Transmission electron microscopy studies reveal the existence of varying morphologies of few layers of MoS2 as well as quantum dots due to the different absorbing effects of two mixed solvents on MoS2. The X-ray diffraction, electron paramagnetic resonance, and Raman studies indicate the presence of physical as well as chemical adsorption of oxygen atoms in MoS2. The photoluminescence spectra show the tuning of bandgap arising from the passivation of trapping centers leading to radiative recombination of excitons. The value of work function obtained from scanning Kelvin probe microscopy of MoS2 in mixed solvents of H2O2 and N-methyl-2-pyrrolidone increases with an increase in the concentration of H2O2. A linear relationship could be established between H2O2 content in mixed solvent and measured values of work function. This work gives the alternative route towards the commercial use of defect engineered transition metal dichalcogenide materials in diverse fields.

The wear behavior of the chromium nitride (CrN) coating on piston ring material against liner material was investigated under dry conditions at room temperatures. Cat iron alloy, widely used in manufacturing of piston rings and cylinder liners, further it was coated by physical vapour deposition method. Wear tests were carried out on a Pin on Disc tribometer, Simultaneous effect of sliding velocities (0.3, 0.4, 0.6 & 0.8 m/s) and corresponding loads (10, 20, 30 & 40 N) on wear rate, friction coefficient and temperature were analyzed. In conclusion, Specific wear rate is decreasing by increase in load and velocity. The rise of temperature is 28 0 C to 42°C at the wear track room temperature resulted in a reduced coefficient of friction (COF) when the increase of load from10 to 40N.The wear mechanism is mixed mode such as three body abrasion and oxidation wear for dry conditions.