Jute fibres (Corchorus olitorious), an environmentally and ecologically friendly product, were chemically modified and treated with 5% NaOH solution at room temperature for 2 h, 4 h and 8 h. The above samples were characterized and morphologically analysed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Instron 1185. Alkali treatment affects the supramolecular structure of the fibre as shown by XRD by improving the degree of crystallinity of the fibre. Surface chemistry of the fibre also altered as depicted by FT-IR studies. This chemical treatment was also found to alter the characteristic of the fibre surface topography as seen by the SEM. From the mechanical single fibre test it was found that the tenacity and modulus of the fibre improved after alkali treatment. This might be due to the improvement in the crystallinity. DSC data demonstrated that the thermal degradation temperature for the cellulose get lowered from 365⋅26°C to 360⋅62°C after alkali treatment led to the reduction in fibre thermal stability. Jute fibre reinforced composite were prepared with treated and untreated jute fibre (15 wt%) reinforced unsaturated polyester (UPE). Effectiveness of these composites was experimentally investigated through the study of the composites by DSC, Instron 1195 for mechanical property of composites, volume fraction of the porosity and hydrophobic finishing of the composite. From the DSC analysis it was found that thermal stability enhanced for treated fibre reinforced composite. This could be due to the resistance offered by the closely packed cellulose chain in combination with the resin. Flexural strength of the composite prepared with 2 h and 4 h alkali treated fibre were found to increase by 3⋅16% and 9⋅5%, respectively. Although 8 h treated fibre exhibited maximum strength properties, but the composite prepared with them showed lower strength value. Alkali treatment helped in the development of hydrophobicity and reduction in volume fraction of the porosity. This may be due to the better fibre matrix interface adhesion caused due to the fibre surface treatment by alkali.

Control of the spin degree of freedom of an electron has brought about a new era in spin-based applications, particularly spin-based electronics, with the potential to outperform the traditional charge-based semiconductor technology for data storage and information processing. However, the realization of functional spin-based devices for information processing remains elusive due to several fundamental challenges such as the low Curie temperature of group III-V and II-VI semiconductors (<200 K), and the low spin-injection efficiencies of existing III-V, II-VI, and transparent conductive oxide semiconductors in a multilayer device structure, which are caused by precipitation and migration of dopants from the host layer to the adjacent layers. Here, we use catalyst-assisted pulsed laser deposition to grow, for the first time, oxygen vacancy defect-rich, dopant-free ZrO2 nanostructures with high TC (700 K) and high magnetization (5.9 emu/g). The observed magnetization is significantly greater than both doped and defect-rich transparent conductive oxide nanomaterials reported to date. We also provide the first experimental evidence that it is the amounts and types of oxygen vacancy defects in, and not the phase of ZrO2 that control the ferromagnetic order in undoped ZrO2 nanostructures. To explain the origin of ferromagnetism in these ZrO2 nanostructures, we hypothesize a new defect-induced bound polaron model, which is generally applicable to other defect-rich, dopant-free transparent conductive oxide nanostructures. These results provide new insights into magnetic ordering in undoped dilute ferromagnetic semiconductor oxides and contribute to the design of exotic magnetic and novel multifunctional materials.

Poly(vinylidene fluoride)‐Graphene Oxide composite films were prepared by solution casting followed by hot press technique with variation of Graphene Oxide content up to 1.6 vol%. High Resolution Scanning Electron Microscope and Raman spectroscopy were used to investigate the morphology and the dispersion of GO. X‐ray diffraction (XRD) and Fourier transform infrared spectra were analyzed to identify and estimate the fraction of β phase. All the composite film samples are found to have fraction of β phase >80%. Dielectric constant of the composite films increases with increase in Graphene Oxide content up to 0.15 vol% and with further increment; it causes decrease in dielectric constant. Both dielectric loss tangent and ac conductivity show increasing trend with increment of Graphene Oxide content. Both remnant polarization and energy density are affected by Graphene Oxide loading. Remnant polarization increases with Graphene Oxide content whereas energy density follows the same variation trend that of dielectric constant.

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