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Microreactor technology is a new concept of chemical synthesis for nanoparticle production. The "state of the art" in microreactor fabrication and its application to the synthesis of nanoparticles is reviewed. The microfluidic concepts, the materials and technologies for microreactor manufacture, with particular emphasis on polymers and microreplication techniques, and their application to the synthesis of various nanomaterials in microreactors are presented. The unique synthesis properties of various nanoparticles using a microfluidic process as well as broader impact in term of nanomaterials engineering, i.e., selectivity and monodispersity, reduced amount of chemicals, fast reaction, minimum cost, a better control of the process, minimum waste and reduced amounts of reaction byproducts and improved safety, are discussed in comparison with the traditional wet-chemical batch synthesis approach.

In this paper, we report a convenient and informative procedure for detecting the morphology and surface structure of individual gold nanocrystals using digital Crystal Image Software (CIS) processing of transmission electron microscopy (TEM) image, which comprises coalescence phenomena of these nanoparticles. The results show that the internal structure of Au nanoparticles has a core of gold atoms arranged as a Marks decahedron, surrounded by additional gold–organic compound layers forming a rigid surface layer, and its outer layer comprises four staple motif bridge molecules that resemble handles, formed an unusual pattern. The obtained results improved our understanding of the basics of the coalescence phenomena such as the driving mechanisms acting at different particle sizes. However, these discrete natures of the nanoparticles will assist in the understanding of principles of nanocore assembly and opens a new window for nanoparticles chemistry.

A simple theoretical method is developed to study the size dependence of bulk modulus, Young modulus, and coefficient of volume thermal expansion of nanomaterials. We have considered different nanomaterials, viz., Ni (spherical, nanofilm), α-Fe (spherical), and Cu (nanowire). The results obtained are compared with the available experimental data. A good agreement between theory and experiment supports the validity of the model developed in the present work.

Reducing cost and increasing efficiency are the principal drivers in photovoltaic technology. Nanotechnology has shown particular promise since it can offer solution to both problems either by improving the existing technologies or helping to replace them with alternative solutions. Nanomaterials can contribute from different ways. The solar cell designs and enhancements play important role in their performance and categorized by the type of nanostructure utilized. This review paper focuses on different possible contribution of nanomaterials in solar cell and describes their promising role and their obstacles.

In recent times, nanomaterials have attracted the interest of the scientific community with their superior applications when compared to bulk counterparts. Tungsten oxide (WO₃) nanoparticles (NPs) with their distinct properties such as electrochemical, photocatalytic, photoluminescent and gas sensing capabilities, are highly sought out. With these distinct properties, WO₃ NPs find significant application in device fabrication. This review provides an overview of the different synthesis methods, the properties and applications of tungsten oxide and doped tungsten oxide. The enhanced properties of WO₃ NPs with doping are also discussed in detail. In addition, this review also emphasizes on properties of WO₃ polymer nanocomposite and their applications in several areas of human enterprise.

This paper reports the synthesis and analysis of the characterization results of PbS and PbS/ZnO core/shell nanoparticles embedded in Polyvinyl Alcohol (PVA) matrix. The technique adopted in this work is wet chemical synthesis of PVA/PbS and PVA/PbS/ZnO core/shell nanoparticles. In total, two different sets of samples comprising of nine samples have been synthesized by altering parameters like PVA concentration and shell thickness for the PVA/PbS and PVA/PbS/ZnO samples, respectively. Various characterization techniques are used to analyze the influence of alteration of matrix concentration and shell thickness upon the as-synthesized nanoparticles. The techniques include UV-Vis Spectroscopy (UV-vis), Photoluminescence (PL) Spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Analysis of X-Rays (EDAX) and Transmission Electron Microscopy (TEM). Results of the characterization techniques confirm the formation of nanoparticles of PbS and PbS/ZnO, respectively.

This interesting study focuses on the contribution of dopant such as “Fe” as a ferromagnetic material in the lattice sites of WO₃$\cdot$H₂O nanopowders, which were synthesized using a cost-effective microwave irradiation procedure and then annealed at $600^{\circ }$C in air for 6h in order to increase the crystallinity of the end products and also to eliminate impurities obtained during the synthesis process. The main focus is to understand the magnetic behavior of the end products for the first time using novel synthesis approach. The samples were further characterized using powder diffraction of X-rays (XRD), field emission scanning electron microscope (FE-SEM), diffusion reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FT-IR) and the corresponding magnetic behaviors of the products were carried out with the help of vibrational sample magnetometer (VSM). According to the diffraction patterns, both pure and doped samples belong to the hexogonal phase. On the other hand, the annealing effect made an impact on the samples that were formed with the same paranet phase. The samples had an influence on the growth rate and morphology at microlevel of the generated nanoparticles, according to FE-SEM micrographs. The optical band gap of these samples was determined using UV–VIS–DRS spectroscopy and the results revealed the contribution of dopant materials in the optical band gap ($E_g$) values using the KM model, as well as a 450nm wavelength revealed blue shift. The exciting results of hysteresis loops from vibrating sample magnetometer on annealed samples showed that doped samples that tend to explore high into the ferromagnetic state may investigate the further nonsuper conducting behavior of the end products prepared using microwave irradiation technique.