Enhanced Electrical Properties of Crystalline Silicon Solar Cells via Nano-Composite Polyvinyl-Alcohol/Titanium Dioxide

Reflection loss and solar cell temperature both have a significant impact on solar cell efficiency and, consequently, on power generation. Herein, the aim is to investigate into the impact of Nanocomposite Titanium Dioxide (TiO2)/Polyvinyl Alcohol (PVA) on polycrystalline silicon solar cells. The solvent casting method is employed to prepare nanocomposite TiO2/PVA for deposition on the front side of the solar cell. The Tauc plot is used to investigate the influence of TiO2 nanoparticle concentration (10-20nm) on the energy bandgap of a nanocomposite. To test the optical properties of the solar cell after depositing the Nanocomposite coating film and to confirm the suspension of TiO2 in PVA and construct a Nanocomposite, an ultraviolet-visible spectrometer and a Fourier transform infrared spectrometer are provided. The results show that increasing the TiO2 in the TiO2/PVA Nanocomposite increases the energy bandgap. The Ultraviolet-Visible spectrometer observes that the Nanocomposite films absorb the Ultraviolet wavelength and transmittance at the visible wavelength. Finally, it found the lowest reflection obtained was 3.9% for 0.2wt% TiO2 in TiO2/PVA nanocomposite and the enhancement of the solar cell efficiency was (+2.3%).

Investigating the Effect of Dwell Time on the Physical Properties of Nano-sized Tin dioxide (SnO2) Prepared Through a Continuous Microwave Flow Process

Tin dioxide (SnO2) is a well-known catalytic material used to catalyze different organic dyes and gas sensors. Similarly, it is also considered a good sensing and optoelectronic material. In this work, SnO2 has been synthesized using a microwave-assisted continuous flow method. The effect of dwell time was utilized to study its effects on the physical properties of SnO2. X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Transmission Electron Microscopy (TEM) and Bruner Emmit-Teller (BET) techniques were used to characterize the synthesized SnO2. UV-Visible spectroscopy technique was employed to calculate the energy bandgap, which exhibited a decrease in the energy bandgap from 3.44 to 3.33 eV on increasing the dwell time. XRD results exhibited an increase in the degree of crystallinity from 56 to 63% and a reduction in the particle size from 3.74 to 2.75 nm. Where, BET study revealed a shrinkage in the surface area from 159 to 154 m2g- 1. Photoluminescence (PL) study was conducted to investigate the surface defects. Photocatalytic efficiency of the SnO2 was probed against the photodegradation of methylene blue dye and this study revealed that SnO2 is a good photocatalytic material.

Structural and Optical Properties in thin-films of (GeGa2)100-x(Sb2Ga3)x (x = 15, 30, 45, 60) Alloys

Investigation of structural morphology and optical parameters of non-oxide (GeGa2)100−x (Sb2Ga3)x (x = 15, 30, 45, 60) glass alloys have been studied in the present paper. Thin films of prepared bulk samples by melt quenching technique were obtained using thermal evaporation method. XRD, DSC and SEM were used to investigate the structural morphology and thermal properties of materials. The linear and non-linear optical properties of prepared samples have been studied for optoelectronic applications. FTIR transmittance spectra defines the impurities present in the prepared glassy alloys. It was observed that energy bandgap (Eg) obtain by Tauc’s plot varies from 2.9 eV to 1.25 eV. The calculated value of k, Eg decreases whereas the α and Urbach energy increases with increasing doping Sb concentration. The decrease in energy bandgap is discussed on the basis of Mott and Davis model.

The Structural, Electronic and Optical Properties of Hydrofluorinated Germanene (GeH1-xFx): A First-Principles Study

The structural, electronic, and optical properties of hydrofluorinated germanene have been studied with different occupancy ratios of fluorine and hydrogen. The hybridization of H-1s and Ge-4p orbitals in hydrogenated germanene and F-2p and Ge-4p orbitals in fluorinated germanene plays a significant role in creating an energy bandgap. The binding energy and phonon calculations confirm the stability of hydrofluorinated germanene decreases with the increase of the F to H ratio. The value of the energy bandgap decreased by increasing the ratio of F and H. The optical properties have been studied in the energy range of 0-25 eV. Six essential parameters such as energy bandgap (Eg), binding energy (Eb), dielectric constant ε(0), refractive index n(0), plasmon energy (ћωp), and heat capacity (Cp) have been calculated for different occupancies of H and F in hydrofluorinated germanene for the first time. The calculated values of structural parameters agree well with the available experimental and reported values.

Study the Effect of the Volumetric Ratio of Alq3 on the Optical and Structural Properties of the Alq3:NPD Blend for the UV Photodetector Applications

The effect of the volumetric ratio of the tris(8-hydroxyquinoline) aluminum (Alq3) on its blend with the N,N'-Di [(1-naphthyl)-N,N'-diphenyl]-(1,1'-biphenyl)-4,4'-diamine (NPD) (Alq3:NPD) is investigated and optimized for the UV photodetectors fabrication. The optical and structural properties of Alq3:NPD blend with different volumetric ratios 1:1, 2:1, and 3:1 is studied in the context of the absorbance, transmittance, optical energy gap and XRD patterns. Results show that the absorbance is increased by 11% at A = 260 nm with the increase in the volumetric ratio. In contrast, the optical energy bandgap that is extrapolated from the Tauc’s plot is decreased with the increase in the volumetric ratio, and the 2:1 ratio shows the lowest energy in the UV region. In terms of the XRD investigation, the 2:1 volumetric ratio shows the highest intensity for the crystallinity peak at 36.6°. The fabricated photodetector with a different volumetric ratio of the active layer Alq3:NPD blend shows the best performance with the ratio 2:1.

Synthesis of naked vanadium pentoxide nanoparticles

Vanadium pentoxide α-phase and β-phase synthesized by Pulsed Laser Ablation in Liquids, exhibiting a 2.50 eV and 3.65 eV energy bandgap.