Polyvinylidene fluoride (PVDF) has attracted significant attention for the fabrication of nanogenerator devices due to its remarkable flexibility, chemical compatibility, and long-term durability. However, its inherently low piezoelectric response compared to ceramic materials necessitates the incorporation of nanofillers to enhance its functional properties. In this work, rutile-phase titanium dioxide (R-TiO2) nanoparticles were incorporated into a PVDF matrix at various weight percentages using the solution-casting technique. The resulting nanocomposite films (NCFs) were systematically characterized to evaluate their structural, optical, and piezoelectric properties. Incorporating metal oxide notably enhanced the electroactive beta-phase content, dielectric constant, electrical conductivity, and remanent polarization of the nanocomposite materials. The beta phase fraction reached a maximum of 77% at 2.4 wt% filler loading. The dielectric constant and electrical conductivity showed enhancements of approximately threefold and fivefold, respectively. At 2.4 wt% R-TiO2, the remanent polarization exhibited a remarkable tenfold improvement, accompanied by a twofold increase in the coercive field. Additionally, the output voltage produced under mechanical stress demonstrated a fivefold increase at a 2.4 wt% filler concentration, emphasizing the significant promise of these nanocomposites for advanced pressure-sensing applications.

High-performance carbonaceous nanofiller (MWCNT) reinforced epoxy nanocomposites at different compositions were synthesized using the ultrasonication dual mixing method. The static and dynamic mechanical properties of the nanocomposites were examined. At 0.8 wt.% of nanofiller, the epoxy nanocomposite greatly improved in tensile strength by about 22.1% and Young's modulus by about 18.5%. The dynamic mechanical analysis showed a significant improvement in the storage modulus of about 19.1% and glass transition temperature of about 15.1% of the epoxy nanocomposite. This improvement may be attributed to the formation of an effective interface between the epoxy and MWCNT. The static and dynamic mechanical properties of the epoxy matrix were significantly improved as a result of the homogenous dispersion of carbonaceous filler in the epoxy matrix.

The dielectric properties of polymers at extreme temperatures for energy storage require significant improvement, despite their superior processability, strong dielectric breakdown strength, and great mechanical qualities. By combining the best features of polymers and ceramics, scientists have created polymer nanocomposites with enhanced dielectric properties, making them ideal for use in various applications, including aerospace, oil and gas exploration, and hybrid electric cars. Interfacial design, microstructural engineering, and new high-dielectric filler materials are some of the important tactics and analytical models that have been developed to significantly increase the energy density of composite dielectrics. Novel designs have resulted from combining analytical models with machine learning approaches. Also covered in this study is the effect of a high-temperature implanted nanofiller on energy density in a polymer matrix. Lastly, this review summarizes the many types of dielectrics and their respective benefits, advancements, drawbacks, and limits when subjected to wide temperature ranges. An overview of the current areas where there is increasing production of energy storage devices in electric vehicles, pulsed warfare systems, and power electronics is provided to illustrate the practical uses of polymer nanocomposite dielectrics. We conclude by discussing the difficulties and potential benefits of polymer nanocomposite dielectrics in unusual scenarios.

Polyvinylidene Fluoride (PVDF) polymer-based nanocomposites are known for their high optoelectronic, dielectric, and electrochemical properties. In the present work, anatase phase Titanium dioxide (A-TiO2) reinforced PVDF nanocomposite films are prepared by the solution casting method to enhance the optical and dielectric properties. The morphology of nanocomposite films is studied by Field Emission Scanning Electron Microscopy (FESEM). The optical properties of prepared nanocomposite films for various compositions of A-TiO2 are estimated using UV-visible spectroscopy. The direct and indirect band gap decreases from 5.93 to 4.45 eV and 4.76 to 3.70 eV respectively for 4 wt% of A-TiO2 nanoparticles. The enhanced absorption in the UV region makes the current material a potential candidate for shielding UV radiations. After filler reinforcement, there is a significant increase in the refractive index and optical conductivity values for nanocomposite films. Thus, nanocomposite films can find many applications to block UV rays, and develop solar cells, and flexible optical devices.

HKUST-1, a Cu-based MOF: Hong Kong University of Science and Technology-1, also called MOF-199, was synthesized by the solvothermal method using water and ethanol as toxic-free solvents for the photocatalytic decomposition of Methylene Blue (MB) dye. The sample of HKUST-1 was characterized by optical band gap of 3.60 eV, crystallite size of 19 nm, and a high surface area of 315 m2/g. The photocatalytic tests conducted under basic conditions show a remarkable 98.94 % degradation of MB within 90 min as compared to acidic and neutral conditions. The reaction follows first order kinetics. The FTIR spectra reveal the presence of functional groups having nitrogen, sulfur, and halo-compounds in the extracted catalyst. Specifically, the FTIR bands corresponding to chemisorption of water with Cu sites, traces of succinic acid, nitro-compounds, aliphatic ether, and halo-compounds are observed. The structural changes in HKUST-1 after photocatalytic deployment were investigated via a unique approach of acquiring Raman spectra at varied intensities. The distinguishing results were obtained for surface and bulk dynamics of the material, which give insights into the recoverability of the photocatalysts. The peaks corresponding to sulphonic groups, N-groups and their interaction with the carbon or the metal open sites are observed. While additional peaks due to the dye compounds observed on the exterior of HKUST-1 disappear after recovering the catalyst, complete retrieval of it is not observed in the spectra corresponding to the bulk HKUST-1. The investigations disclose that structural deformations are permanent in HKUST1 after using it as a photocatalyst. This is also confirmed by the XRD pattern of HKUST-1 after dye degradation, which shows defective cubic structure. This study highlights a novel technique to probe the interaction mechanism between a photocatalyst and contaminant through the intensity varied Raman Spectroscopy.

Nanowire Field Effect Transistors (NWFETs) have been considered as the next-generation technology for sub-10 nm technology nodes, succeeding FinFETs. However, the highly confined nature of Nanowire FETs creates reliability issues that significantly impact their performance. Therefore, this work proposes a machine learning- based technique for analyzing the self-heating-induced reliability issues in NWFETs. The influence of self-heating effects in NWFET has been predicted in terms of saturation current (Idsat), threshold voltage (Vth), the maximum carrier temperature along the channel (eTmax), and the maximum Lattice temperature (LTmax) with multi- variable regression. TCAD-assisted machine learning has been used for algorithm training and prediction. A dataset has been created by varying the parameters of the NWFETs like the thickness of the channel (tsi), the thickness of oxide (tox), Length of source/drain (Lsd), length of source/drain contact (Lsdc), doping concentrations etc. The Random Forest Regression algorithm has been used to estimate the performance of NWFETs in predicting the desired output parameters suitably with the given dataset.

In this work, two different types of nanofillers yttrium oxide (Y2O3) or yttria and reduced graphene oxide (RGO) are used to reinforce with epoxy polymer for the synthesis of epoxy nanocomposites by using the ultrasonication dual mixing approach. Raman spectroscopy has been done to analyze the microstructure of yttria and conformation of the formed RGO from Graphene oxide. The viscoelastic behavior of epoxy nanocomposites is evaluated with the help of the dynamic mechanical analyzer. Further Storage modulus is used to determine the cross-link density 'nu e', coefficient of effectiveness 'C factor', and reinforcement efficiency factor 'r factor'. The damping coefficient (Tan delta) helps in determining the glass transition temperature of the epoxy and its nanocomposites. The results demonstrate that at 1.6 wt% Y2O3 & 0.8 wt% RGO reinforcement in pure epoxy matrix showed maximum enhancement in terms of storage modulus, loss modulus, and glass transition temperature. The semi-circular shape that resulted from the study of the Cole-Cole plot of all the nanocomposites demonstrated the homogenous dispersion of nanoparticles and efficient bonding between epoxy and nanoparticles. Field Emission Scanning Electron Microscopy (FESEM) has been used to identify the interfacial interaction between nanoparticle and epoxy matrix through tensile fracture surfaces.

In the present study, anatase phase titanium dioxide (A-TiO2)-reinforced polyvinylidene fluoride (PVDF) nanocomposite films are synthesized by the solvent casting method. The electroactive phase, dielectric, and piezoelectric properties are studied for A-TiO2 nanoparticles at 0.8 wt.

Two-dimensional transition metal dichalcogenides, especially MoS2, are widely exploited for their proficiency owing to the optimum energy band gap required for photocatalytic mechanism. However, the electron–hole pair recombination hampers the photocatalytic efficiency of pristine 2D MoS2. In this work, multi-walled carbon nanotubes (MWCNTs) are reinforced into 2D MoS2 nanosheets via an ultrasound-driven liquid exfoliation technique to synthesize an efficient photocatalyst. The resulting composite nanosheets are characterized structurally by high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy. The ultraviolet–visible (UV–vis) absorption and photoluminescence spectroscopy reveal changes in the band gap and the recombination rate probability of the photogenerated charge carriers, respectively. The photocatalytic performance of the composite nanosheets is investigated by photodegradation of methylene blue dye. The efficiency of the photocatalysts is studied for varying concentrations of the reinforcement. The values of rate constant (at 665 nm) are 0.0047 min−1 for pristine MoS2 nanosheets, 0.0171 min−1, 0.0177 min−1, and 0.0183 min−1 for MoS2@MWCNT composite nanosheets of 2

The manuscript covers Vanadium Pentoxide Gas Sensors: Elemental Doping Strategies and Sensing Performance Impact. In this paper, we discuss elemental doping ways to improve gas sensing performance in V2O5 sensors. The sensing characteristics of V2O5 are influenced by dopants such as transition metals, rare earth elements, and non-metals. We investigate the processes behind doping-induced enhancements in sensitivity, selectivity, response time, and stability. Additionally, we explore elemental doping issues and constraints, such as precise process control, crystal structural alterations, and dopant concentration implications on sensing characteristics. This study demonstrates the possibility of elemental doping for modifying gas detecting capabilities in V2O5 sensors for various applications.

Epoxy-based nanocomposites are important materials for coating and adhesive applications. The mechanical strength of these materials is desired to be large. The current work aims to enhance the mechanical properties of epoxy polymer by reinforcement of reduced graphene oxide (RGO) or yttrium oxide (Y2O3). Highly efficient and multifunctional epoxy nanocomposites were synthesized by ultrasonication along with magnetic stirring, which helps the proper dispersion of nanoparticles in the epoxy matrix. This work presents a comparative analysis of the two nanofillers. The reduced graphene oxide is synthesized from graphite powder using Hummer’s method. The nanocomposites are prepared using the ultrasonic dual mixing method. The mechanical properties like tensile strength, yield strength, toughness, Young’s modulus, and percentage elongation are determined using the universal testing machine. The composition (1.6 wt.

Molybdenum disulfide (MoS2) is an alternate absorber layer in 2D solar cells owing to its potential of proficient sunlight harvesting. The optimum electrical and optical properties of MoS2 validate it as a suitable photovoltaic absorber material. This work investigates the performance of 2D (and multi-layer) MoS2-based vertically stacked solar cell by numerical simulation process using one dimensional solar cell capacitance simulator (SCAPS). Two device configurations based on Schottky junction (ITO/n-MoS2/Au) and pn junction (ITO/n-MoS2/p-MoS2/Au) have been theoretically analyzed. The feasibility of ultra-thin transparent solar cells is also demonstrated, which is motivating from a technological outlook. Initially, the properties of the active layers are optimized to give the highest performance. The findings are explained on the basis of band alignment between the electrodes and the different layers. The potential barrier developed at the interface of different materials governs the output of the cells. The calculations forecast the material properties, which need to be tuned to fabricate solar cells with enhanced efficiency. After optimization, the highest efficiency obtained for single n-MoS2-based solar cell is 10.22%, while for the pn junction solar cell it is 16.86%. The optimized cells exhibit high open circuit voltages of similar to 1.2 V, which is an essential factor for commercial realization of solar cells. Lastly, the performance of transparent solar cells based on thin 2D MoS2 films has been predicted which showcases the efficiency in the range of 0.78%-4.36%. These homo-junction device investigations of solely MoS2 layer along with employment of a strict control on the defects during deposition and fabrication of MoS2-based solar cells can ensure better performance of the device. Thus, it can open ways to develop next generation feasible solar cells with higher power density as compared to existing technology.

Molybdenum Disulphide (MoS2) based materials in pure form or composites are known for their photocatalytic activity including wastewater treatment and purification. In the present study, pristine MoS2 nanosheets and MoS2@TiO2 composite nanosheets are synthesized via grinding-assisted sonication process with N-Methylpyrrolidone (NMP) as solvent. TiO2 being environment friendly with high photochemical stability, provides a suitable reinforcement material for photocatalytic applications. The prepared dispersions are characterized by UV-Vis, Raman and FTIR spectroscopy for structural and optical properties. These nanosheets are tested for methylene blue dye degradation in dark and in the presence of sunlight at intervals of 30 minutes. The MoS2@TiO2 nanosheets show enhanced degradation efficiency in comparison to the pristine MoS2 nanosheets. These composite nanosheets are potential materials in tackling dye pollutants for application in wastewater treatment plants and purification.

Due to energy crises, development of renewable energy resources is currently in demand. Having superb physical and chemical properties, optical properties of nanocomposite thin films still need to be enhanced. In the current study, recycled Iron oxide (II) Fe2O3 obtained from rust is reinforced in Polyvinylidene Fluoride (PVDF) by solution casting method and analyzed by UV–visible and FTIR spectroscopy. Various parameters such as band gap, extinction coefficient, refractive index, and dielectric constant are calculated from absorption, and reflectance data. A significant decrease in direct and indirect band gap is noted. An increase in refractive index and improvement in the dielectric constant of nanocomposite thin films is observed. FTIR study confirms the enhancement in the β phase of the Fe2O3/PVDF nanocomposite thin films. Morphology of nanocomposite films is analyzed by using FESEM. Reinforced Fe2O3/PVDF nanocomposite thin films can be used for development of new generation pressure sensors and piezoelectric devices.

Development of renewable energy resources can be an alternate source of fossil fuels and helpful in the reduction of pollution present in the environment. Having outstanding physical and chemical properties, polymer nanocomposites with enhanced piezoelectric properties are appropriate candidates for the development of renewable energy devices. Magnetite Iron oxide (II) Fe2O3 is a narrow band gap metal oxide reinforced in Polyvinylidene Fluoride (PVDF) by solution casting method at 0.8, 1.6, 2.4 and 3.2wt.%. Dielectric and optical properties of nanocomposite thin films are analysed by impedance analyser and UV-visible spectroscopy. FTIR and RAMAN are used to analyse the enhancement in b phase of nanocomposite thin films. Various parameters such as absorption coefficient, skin depth, optical density, electrical conductivity, and dielectric constant are calculated for the prepared samples. A significant increase in dielectric constant and b phase is found after the reinforcement of Fe2O3 nanoparticles. Dielectric constant and β phase are found to be maximum for higher concentrations of Fe2O3. Fe2O3 embedded in PVDF nanocomposite thin films are suitable candidates for piezoelectric nanogenerators and pressure sensing devices.

In the present study, MoS2 nanosheets are prepared by a two-step, grinding-assisted ultrasonication technique. Various parameters governing the optical, electrical, and dielectric properties of the MoS2 nanosheets are determined from the absorbance, reflectance, and transmittance spectra acquired using UV-Vis spectroscopy. These parameters are analysed with change in grinding hours as well as for sonication effects. It is observed that the absorption coefficient, optical conductivity, and dissipation factor increase (along with a decrease in refractive index) with increase in grinding hours and with sonication. The obtained changes in the optical parameters are correlated with the number of exfoliated layers revealed by Raman spectroscopy. The results of this study provide insightful information about the layer-dependent properties of MoS2 nanosheets and develop better understanding of how the synthesis routes are effective for tailoring the optical response of MoS2 nanosheets.

Among 2D Transition Metal Dichalcogenides (TMDs), ultrathin molybdenum disulfide (MoS2) nanosheets are well researched in terms of synthesis, characterization and applications owing to its unique properties in contrast to the bulk material. Here, 2D MoS2 suspensions are prepared via grinding-assisted liquid phase exfoliation. The processing parameters like initial concentration of MoS2 powder, grinding hours, solvent and high-power sonication are optimized for efficient and scalable production of MoS2 nanosheets. The suspensions are characterized for their optical and structural properties and are compared to analyze the effect of synthesis conditions on the properties of the obtained samples. The bandgap of the synthesized MoS2 lies above 2.0 eV in contrast with a bandgap of 1.57 eV for bulk sample. The difference between the peaks corresponding to in-plane and out-of-plane vibration modes is lower than bulk sample depicting the formation of mono to few-layered MoS2. It is found that grinding-assisted sonication in NMP solvent is the most efficient method to produce low-dimensional nanosheets. The well dispersed MoS2 nanoflakes can be blended with other nanomaterials to prepare hybrid dispersions and can thus be explored for optoelectronic applications.