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In the present study, Nano Silica (n-SiO2) as cementitious nanomaterial and Nano Zinc Oxide (n-ZnO) as non- cementitious nanomaterial in powder form are doped in the concrete mix to replace the cement by 0.5%, 0.75% and 1.0%. The specimens were casted with a constant Water Cement (W/C) ratio of 0.45 with an M25 mix design. From the experimental results, n-SiO2additives with 0.75% replacement and n-ZnO with 0.5% replacement increase the compressive strength by 16.54% and 6.32% and split tensile strength by 19% and 3.86% respectively as compared to the normal concrete. Hydration of Tricalcium Silicate (C3S) is a significant part of Bogue’s compound. Therefore, in the hydration process reactions of nanomaterials with C3S were investigated in this study. Additional cement gel formation due to n-SiO2helps to increase compressive strength as well as durability of concrete. The formation of the Zn(OH)2layer in the hydration process resists the water in cement. Due to doped nanoparticles, the size acid resistance properties of concrete are increased up to some extent but loses the concrete strength. With the help of optimized composition, the exact constituent of concrete can be easily identified for cementitious and non-cementitious nanomaterial. After that Ultrasonic Pulse Velocity (UPV) test was carried out for tap water and acidic media. The n-SiO2additives, concrete shows an excellent quality as compared to n-ZnO additives. As per UPV test results, n-SiO2additives are more suitable to use in the concrete. The outcome of this study will be helpful to the construction industry in understanding the effect of nano-composite in concrete.

In the field of photovoltaics, perovskite solar cells (PSCs) have become increasingly popular because of their cost-effective processing and competitive efficiency when compared to silicon solar cells. This work presents a novel design of a PSC based on methyl ammonium lead iodide (CH3NH3PbI3) and investigates the possibilities of organic-inorganic metal halides in the field of PSCs. The device has a sandwich architecture, where the hole transport material (HTM) operates at room temperature using a blend of polyvinyl alcohol (PVA) and F-127 polymer. Under typical solar conditions, the built-in PSC, which has the architecture FTO/TiO2/Perovskite/PVA & F-127/Pt, exhibits a remarkable efficiency of 1.29 %. Interestingly, PSC stability at room temperature is still a major problem, yet our design demonstrates a remarkable 2-h stability in ambient circumstances. This accomplishment is ground breaking because it introduces a high-efficiency PSC in a sandwich construction operating in ambient settings for the first time. The fact that this novel technique is solution-based and does not require vacuum deposition lends even more credence to its viability and scalability.

Heterocycles are the main structural motif of DNA and RNA and play a crucial role in various chemical reactions of metabolisms. Therefore, heterocyclic compounds show good physiological and pharmacological properties. Coumarin and pyrazole scaffolds are present in many commercial drug molecules and natural products. This review overviews the progress made in the synthesis and functionalization of the coumarin- pyrazole hybrid heterocycle. It also includes discussion on the possible reactive sites of heterocycles, functionalization, and mechanistic pathways to incorporate pyrazole pharmacophore unit in synthesis. Several synthesis and biological studies reveal that the combination of the coumarin-pyrazole moiety is a prominent structural motif to find lead compounds in drug discovery.

Minimization of stress-induced mechanical rupture and delamination of conducting polymer (CP) films is desirable to prevent failure of devices based on these materials. Thus, precise in situmeasurement of voltage-induced stress within these films should provide insight into the cause of these failure mechanisms. The evolution of stress in films of polypyrrole (pPy), doped with indigo carmine (IC), was measured in different electrochemical environments using the multibeam optical stress sensor (MOSS) technique. The stress in these films gradually increases to a constant value during voltage cycling, revealing an initial break-in period for CP films. The nature of the ions involved in charge compensation of pPy[IC] during voltage cycling was determined from electrochemical quartz crystal microbalance (EQCM) data. The magnitude of the voltage-induced stress within pPy[IC] at neutral pH correlated with the radius of the hydrated mobile ion in the order Li+> Na+> K+. At acidic pH, the IC dopant in pPy[IC] undergoes reversible oxidation and reduction within the range of potentials investigated, providing a secondary contribution to the observed voltage-induced stress. We report on the novel stress response of these polymers due to the presence of pH-dependent redox-active dopants and how it can affect material performance.

Voltage-induced ion motion in conducting polymers (CPs) and the associated stress that evolves play an important role in determining the performance and lifetime of devices fabricated from these materials. In this work, a multi-beam optical stress sensor (MOSS) coupled with potential cycling was used to study films of polypyrrole (pPy) doped with indigo carmine (IC), a redox-active anion. We observe different magnitudes of stress in these films in different electrolytes (NaCl vs. HCl) due to the pH-dependent redox activity of IC. These results indicate that the redox activity of a dopant introduces an additional mode by which stress develops in films of CPs, which in turn could impact device performance.

Viologen‐modified poly(vinylphosphonic acid) is synthesized by a simple EDC coupling reaction and characterized by FTIR and 1H NMR spectroscopy. Electrochemical studies of the polymer are performed in solution and on a skin‐printed electrode, the latter after making a composite with TEOS. A first redox peak is found at E0= −0.57 V. The polymer is found to show diffusion‐confined phenomena in solution and surface‐confined phenomena on the electrode. On increasing the silica content, an increase in the resistivity of the film is found, which is reflected in an increase of the anodic‐to‐cathodic peak separation. From a plot of the current vs. the scan rate, the surface concentration of the redox‐active species is found to be 2.5 × 10−10mol · cm2.

Mesoporous ZnO nanoparticles with average pore sizes of 2.5 and 14.3 nm were prepared by ultrasonic hydrolysis of zinc acetate at different ultrasound powers. Morphology, crystallinity, and porosity of the materials have been studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), and BET nitrogen adsorption. Whereas a moderate ultrasound power favored the synthesis of well-crystalline mesoporous ZnO nanoparticles of triangular and hexagonal morphologies with very low density of lattice defects and small pore size, high ultrasound power generated mesoporous ZnO nanoparticles of arbitrary morphology with higher density of lattice defects. Photoluminescence behaviors and the mechanisms of formation of the two types of porous nanostructures are discussed.

Nanoparticles of europium-doped yttrium oxide (Y2O3:Eu3+) were synthesized by coprecipitation method with use of different surfactants like butanol, hexanol, and oleic acid. The as-prepared Y2O3:Eu3+samples were annealed at 800 °C and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and UV−visible and photoluminescence (PL) spectroscopy techniques. The nanoparticle shows cubic phase structure. Surfactant helps to inhibit or control the particle growth and avoids agglomeration of nanoparticles effectively by reducing the oxygen bridge bonds between the particles. The most intense red emission peak occurs at 614 nm at an excitation wavelength of λ = 200 nm. Nanoparticles of Y2O3:Eu3+with a particle size of 30 nm synthesized by using oleic acid with NaCl show a 73% rise in PL intensity of the 614 nm peak.