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The current article reviews the construction of thin films comprising carbon-based nanomaterials for application in electrical and electronic fields. Carbon-based materials such as carbon nanotubes, graphene, and fullerene are known to possess excellent electrical and electronic properties, which makes them desirable materials for the fabrication of micro- and nano-electromechanical devices. The fabrication process of thin films, including the deposition of several layers, removal of layers, solution processing methods, inkjet printing, micro-emulsion polymerization methods, deposition through filtration processes, spin coating, dip coating, pen lithography, vacuum-assisted flocculation, vacuum-assisted layer-by-layer assembly laser writing, etc., has been extensively reviewed. It is evident from the past findings that the fabricated thin films constituting carbon nanomaterials shows predominant alteration in electrical and electronic properties like sheet resistance, ionic transport, potential difference, conductivity, electro-rheological, transparency, trans-conductance, transmittance, bending stability, etc. In view of the referred properties, the developed materials find wide applications in charge-trap flash memories, flexible organic resistive memory devices, photovoltaic devices, flexible and transparent electronics, heat sinks in electronic materials, liquid crystal displays (LCDs), thin-film solar cells, flexible touch-screen panels, electronic papers, micro-batteries, electrochemical micro-capacitors, humidity sensors, optoelectronic devices, etc. We expect that the current review article will be a valuable asset for the researchers working in the field of carbon nanomaterials.

Wear and hardness behaviour of aluminium metal matrix composite is investigated. The matrix is aluminium LM4 and reinforcement is nano alumina and Molybdenum (Mo). The composites were fabricated in different composition by varying the weight fraction of matrix and reinforcement. The reinforcement nano alumina is nano size and Mo is micro sized. The reinforcement alumina varies with 1, 1.5, 2.5 and 5% of weight fraction and Mo was kept constant of 0.5% in all composition. Stir casting method is used to fabricate the composite. Wear test carried out on pin on disc wear testing machine under dry sliding conditions and constant sliding distance and hardness test carried out by Rockwell hardness testing machine. This work mainly emphasis on the variations of hardness and wear properties by varying the reinforcement composition by weight percentage. The wear resisting rate and hardness of the material increased gradually by adding the nano alumina and Mo. Observed that reinforcement 5% of nano alumina, 0.5% Mo with matrix showed that better in wear resistance and hardness.

In most of the optoelectronics or photovoltaic based devices, different kinds of anti-reflection coatings on the substrate is mainly developed by sol-gel based coating process includes spin, dip and spray pyrolysis coatings. This paper enumerates in details regarding fabrication of thin films with its essential chemical procedures using sol-gel technique. Further it outlines about structural characterization and influences of physical and chemical parameters on the antireflection coatings prepare by sol-gel practice procedure. The essential coating on the substrate mainly depends on the heat treatment process, solution preparation and coating types using sol-gel application. The coated layer behaviour mainly relies on the ration of solvent to additive substances, concentration of taken precursor agent, and aging time of the solvent, thickness and substrate material of the coating. Among various coatings mainly anti-refection coating by sol-gel technique holds much attractiveness towards implementation due to its feasibility, low cost and compactness.

Transparent zinc sulfide (ZnS)-aluminium sulfide (Al2S3) composite thin-films are deposited on silicon solar cells through radio frequency (RF) sputtering method at room temperature to investigate the structural, optical, electrical, and thermal characteristics. X-ray diffraction analysis reveals the presence of the powder sample (ZnS-Al2S3) and its average crystallite size is 15.83 nm. The minimum electrical resistivity (ρ), maximum hall mobility (μ), and carrier concentration (N) of ZnS-Al2S3 nano-layer coated solar cells are measured to be 2.98 × 10−3 Ω cm, 14.89 cm2 V−1 s−1 and 24.88 × 1020 cm−3 respectively. For a time period of 25 min, ZnS-Al2S3 nano-layer sputter coating produces the maximum power conversion efficiencies (PCE) of 19.38% and 21%, obtained at open and controlled atmospheric conditions, respectively. The influence of operating temperature at both these open and controlled atmospheric conditions for ZnS-Al2S3 nano-layer coated silicon solar cells is observed. The ZnS-Al2S3 composite demonstrates the properties of a desirable anti-reflection coating material for enhancing the PCE of solar cells.

The present paper deals with the study of hardness and wear characteristics of Al2O3 (Nano size) and TiB2(Nano size) reinforced aluminum LM25 Metal Matrix Composites (MMC). Matrix alloy with 1, 1.5 and 2, 5% of Al2O3 and TiB2 were made using stir casting technique. A pin on disc wear testing machine was used to find out the wear rate in which E24 steel disc under dry condition and Brinell hardness testing machine was used to find the hardness of the both material made by stir casting. This work mainly emphasis on the comparison of hardness and wear property of the casted material. The wear properties compared in both load and unload conditions. Wear resistance and hardness of the material will be increased when adding the Al2O3 and TiB2. The results shown properties of stir casting material having composition 2.5% Al2O3+ 2.5% TiB2 + 95%LM25 is good compared to the other composition. Because of good dispersion of Nano powders.