Optical Band Gap Values Research Articles

Physical Properties of HfO2 Nano Structures Deposited using PLD

On Quartz substrates, high purity transparent conductive the Di-Oxide of the (HfO2) Nano and micro-structure films were successfully coated. The method of (PLD) Deposition using Pulsed Laser, and the influence of laser energy was investigated. The XRD results revealed two distinct phases, cubic and monoclinic crystal shapes. Peaks in the Fourier-transform infrared (FTIR) spectra showed that HfO2 nanofilm was forming.The findings of the optical characteristics reveal an excellent transparency of nearly 80% (89 percent). As the laser wavelength decreases, the optical energy band gap values for Nanostructure of HfO2 were prepared, with values ranging from 5.24 to 5.53 eV. Also, the EDX results showed the appearance of hafnium peaks and oxygen peaks in varying proportions, which confirms that hafnium oxide is definitely obtained The results of the AFM reveal that when the pulsed laser intensity increases, the average grain diameter values increase from 52.96 to 74.54 nm. With regard to optimum pulsed laser energy, the based on I-V characterization, the generated factor ideality for created diodes was discovered to be decreasing, and the corresponding values of the barrier height grew. The ideality factor of the diode made the optimum pulsed laser energy (1800 mJ) was greater (n=3.1).

Effect of substrate temperature on In2S3 thin films using nebulizer spray pyrolysis method for photodetector applications

In this work, Indium Sulfide (In2S3) thin films were prepared using an economical nebulizer spray pyrolysis technique by various substrate temperatures from 250 °C to 375 °C in steps of 25 °C to evaluate their photo sensing properties. X-ray diffraction (XRD) patterns confirm the presence of In2S3 with face centered cubic structure for all substrate temperatures. The densely packed small spherical grain-sized particles were observed for In2S3 films deposited at 350 °C using Field emission scanning electron microscope (FESEM) analysis. The optical bandgap values were decreased from 3.16 eV to 2.28 eV, with increment in coating temperatures from 250 °C to 350 °C. The high intensity Photoluminescence (PL) peak is observed at 480 nm for the film coated at 350 °C is due to higher rate of electron–hole pair recombination. The photo sensing analysis revealed that the In2S3 thin films deposited at 350 °C, has the maximum responsivity (R) of 9.09 × 10−2 A W−1, detectivity (D*) of 8.25 × 1010 Jones, and external quantum efficiency (EQE) of 21.2%. Increasing the substrate temperature results in a significant enhancement of photo sensing characteristics.

Investigation of the microstructural, surface, and optical properties of WO3-doped ZnO thin films

The paper investigates the microstructural characteristics, surface features, and optical properties of WO3-doped ZnO thin film. The deposited samples exhibit polycrystalline characteristics, with reflections corresponding to bimetal oxides and metals. Specifically, ZnO shows (101) and (200) reflections, while (400) reflections are observed in the WO3 phase of the deposited sample. The crystallite sizes of the ZnO metal oxide phase in the film are 85 nm and 55 nm, while the crystallite size of the Zn nanoparticles is found to be 47 nm. The atomic concentrations of W and Zn are 53.4 % and 46.6 % for films deposited on uncoated glass, and 41.2 % and 58.8 %, for films deposited onto ITO-coated glass, respectively. An optical band gap value of 3.40 eV was obtained for both films. It was found that certain properties remain relatively unchanged despite variations in the substrate.

Effect of different metallic doping elements on the physical properties of iron oxide thin films

This study investigates the physical properties of pure and Co, Cr, Mn, and Ni-doped Fe2O3 thin films fabricated using spray pyrolysis techniques on glass substrates. The primary aim is to understand how doping influences the structural, optical, and dielectric properties of Fe2O3 thin films. The deposition parameters were kept constant for all samples, with a fixed dopant concentration of 3 weight percent (wt%). X-ray diffraction (XRD) analysis revealed a single diffraction peak indexed as (104), decreasing in crystallite size from 17.27 nm for the pure film to approximately 11.5 nm for all doped films. Field emission scanning electron microscopy (FE-SEM) images displayed non-homogeneous grain formation, characterized by an average grain size larger than the crystallite size, indicating agglomeration. The optical band gap value shifted from 2.54 eV for the pure film to higher values upon doping with various elements, signifying direct allowed transitions. Changes in refractive index dispersion with wavelength were observed based on the dopant type. The application of the Spitzer-Fan model revealed an increase in high-frequency dielectric constant upon doping compared to the pure film, varying across different dopants. Photoluminescence (PL) spectra recorded under excitation at 340 nm exhibited multiple emission peaks within the spectral range of 399 to 600 nm.

Chemical and Green Synthesis, Characterization, Electrical and Antimicrobial Activity of ZrO2 Nanoparticles

ZrO2 nanoparticles were successfully synthesized using a chemical and green synthesis method. Their structural, morphological, optical, anti microbial and electrochemical properties were characterized. The green and chemical synthesis of ZrO2 was achieved by using the ethanolic extract and NaOH as reagents. XRD analysis confirmed the ZrO2 nanoparticles' tetragonal crystal phase. The surface morphological properties under the phases of nucleation, growth and aggregation as well as elementary composition were confirmed by SEM and EDS. The Fourier Transform Infra Red (FTIR) analysis was used to investigate into the functional groups that were present in the molecules of the synthesized nanomaterials. The presence of zirconium oxide nanoparticles with an optical band gap value between 4.73 and 5.48 eV was confirmed by the absorption spectra at 226-232 nm Antimicrobial studies showed that ZrO2 nanoparticles had bactericidal activity at a dose of 10 g/mL against Proteus vulgaris, Eschericia coli, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus. The overall results of this study showed that ZrO2 NPs with excellent bioremediation and antibacterial characteristics were formed. The electrochemical behavior of both ZrO2 nano particles was examined using cyclic voltammetry studies were observed. The maximum enhanced specific capacitance value at a 10 mV/s scan rate.

Optical Characterization of Hydrogel and Silicone Hydrogel Soft Contact Lenses

Contact lenses are biomaterials that have emerged as an alternative to glasses in correcting vision defects. In this study, commercial nesofilcon A (hydrogel-Hy) and delefilcon A (silicone hydrogel-SiHy) daily disposable soft contact lenses were optically examined using UV-visible light spectroscopy. Optical absorption and transmittance measurements of the lenses were taken with a UV-visible spectrophotometer, and their properties of blocking the harmful part of the radiation to the eye and transmitting the harmless part were investigated. From the absorption spectrum, it was seen that the nesofilcon A lens absorbed ultraviolet light better. From the optical absorption coefficient spectra of nesofilcon A and delefilcon A lenses, the absorption edges were obtained as 386 and 325 nm, and the optical band gap values were 3.37 and 3.98 eV, respectively. Additionally, the refractive index profiles of the lenses were plotted. The refractive indices of the lenses at 550 nm wavelength were calculated as 1.55 and 1.77 for nesofilcon A and delefilcon A, respectively. While the delefilcon A lens transmitted visible light well, the nesofilcon A lens blocked UV light better and its refractive index was determined to be closer to the 1.40 the value specified by the manufacturer.

Impact of B2O3/Co3O4 substitution on structure, physical, optical characteristics and photon attenuation capacity of borosilicate glasses

The impact of substitution of B2O3/Co3O4 in borosilicate glasses on their optical, structural, and physical characteristics as well as their ability to attenuate γ-rays was examined. Using the traditional melt quenching process, glass samples with the chemical formula (45-X)B2O3+15SiO2+ 20BaF2+20Na2O + XCo3O4, where X equals 0.0, 0.5, 1.0, 1.5, and 2.0 mol%. The prepared samples were coded as Co-0.0 - Co-2.0. XRD measurements revealed the non-crystalline character of the Co-X samples. The molar volume (Vm) decreased from 31.19 cm3/mol to 31.08 cm3/mol, although the density (ρ) increased from 2.81 g/cm3 to 2.94 g/cm3. When comparing Co-0.0 and Co-2.0, the direct optical band gap (EgDirect) values reduced from 4.32 eV to 3.77 eV, while the indirect optical band gap (EgIndirect) decreased from 3.93 eV to 3.44 eV. The Co-X glasses' Urbach's energy (EU) ranged from 0.297 eV to 0.248 eV. As the ratio of Co2+ ions rose, the optical dielectric constants of Co-X glasses, ε1 (actual part) and ε2 (imaginary portion) were improved. The linear (μ) and mass (μm) attenuation coefficients and effective atomic number (Zef) were followed the order: Co-2.0 > Co-1.5 > Co-1.0 > Co-0.5 > Co-0.0. The created Co-2.0 glass, which has the maximum amount of cobalt (III) oxide, has the lowest mean free path (MFP) and half/tenth value layers (H/TVL). The examined Co-X glasses can be employed for optical and γ-ray shielding purposes, as confirmed by the results.

A comparative study of optical property on unintentionally doped and Sn-Doped β-Ga2O3 crystals by EFG method with a cylindrical Ir die

In this work, we carried out a comparative study of optical property on unintentionally doped and Sn-doped β-Ga2O3 crystals by edge-defined film-fed growth (EFG) method with a cylindrical iridium (Ir) die. The non-polarized Raman spectra showed the anisotropy in Raman peak position and intensity for three different planes (i.e., (100), (010) and (001)) of β-Ga2O3 crystals, independent of the Sn dopant. A difference in the Raman spectra between the unintentionally doped and Sn-doped β-Ga2O3 crystals was observed in the (001) plane. The strong in-plane anisotropy of the monoclinic β-Ga2O3 crystal related to the crystallographic orientation was demonstrated by the angle-resolved polarized Raman spectroscopy. The Sn dopant cannot change the optical transmittance and bandgap values of the unintentionally doped and Sn-doped β-Ga2O3 crystals with the (100), (010) and (001) orientations. However, the Sn-doped β-Ga2O3 crystal with the (010) orientation showed the higher valence band maximum and lower surface barrier height values. The X-ray photoelectron spectroscopy of the unintentionally doped and Sn-doped β-Ga2O3 crystals with the (010) orientation was also measured, which showed no obvious difference. The different luminescence centers and level of electron ionization of the unintentionally doped and Sn-doped β-Ga2O3 crystals were observed by the cathodoluminescence spectroscopy and electron paramagnetic resonance, respectively. Based on the comprehensive comparison, it can be concluded that the anisotropy in optical property of the unintentionally doped and Sn-doped β-Ga2O3 crystals with (100), (010) and (001) orientations apparently exist.

Photocatalytic and magnetic properties of nanocrystalline Er/Eu-doped ZnO samples

Augmentation of optical and magnetic properties of ZnO system via mono- and co-doping is an efficient approach to achieve enhanced ferromagnetism and photocatalytic activity. In this scenario, we made an endeavor to prepare the nanocrystalline ZnO, ZnO:Eu, and ZnO:(Eu, Er) samples through a co-precipitation technique. Structural analysis ruled out the effectual substitution of Eu and Er in the ZnO lattice without disturbing the original structure. Both ZnO:Eu and ZnO:(Eu, Er) NPs exhibited lower optical band gap values than pure ZnO. In M − H studies at room temperature, ferromagnetic behavior was observed in ZnO, ZnO:Eu, and ZnO:(Eu, Er) NPs. Expectedly, ZnO:(Eu, Er) NPs showed highest H2 evolution than both ZnO and ZnO:Eu NPs beneath solar spectrum. The possible roots behind the extended H2 production are discussed in detail. Hence, ZnO:(Eu, Er) NPs may find in applications is photocatalysis and spintronics.

Impact of calcined temperatures on the crystalline parameters, morphological, energy band gap, electrochemical, antimicrobial, antioxidant, and hemolysis behavior of nanocrystalline tin oxide

To construct a battery, the precipitation-synthesized SnO2 products at 450 °C and 650 °C were separately taken and mixed with graphite as the anode and PbO2,V2O5, and graphite materials as cathode materials to make the pellets and examine their open circuit voltage (OCV) values. The microstrain, lattice parameter, and crystallite size values of the above-mentioned tin oxide compounds were obtained through Rietveld refinement-MAUD fit analysis. The microstrain and lattice parameter values of tin oxide were significantly varied at a higher calcined temperature. Surface particle grain growth was increased with the increased calcined temperature from 450 to 650 °C as evidenced by FE-SEM study. Particle size distributions of SnO2 and polycrystalline behavior have been discussed with the aid of TEM analysis. From the UV–visible spectra, optical band gap (Eg) values reduced from 3.73 to 3.69 eV for the SnO2 products with an increase in calcined temperatures from 450 to 650 °C. The antimicrobial responses of the two different calcined SnO2 samples at 450 °C and 650 °C against two different bacterial pathogens (gram-positive-S. aureus and gram-negative-E.coli) were investigated. From the microbicidal assessment, a relatively higher diameter of the zone of inhibition (DZOI) of tin oxide at 650 °C samples was measured to be 19 ± 2 mm and 21 ± 2 mm for S. aureus and E. Coli than the DZOI of SnO2 at 450 °C samples (15 ± 1 mm for S. aureus and 18 ± 1 mm for E. coli. DPPH scavenging activity at 100 μg/ml shows that SnO₂ calcined at 450 °C achieves 68 ± 1 %, while SnO2 calcined at 650 °C exhibits a significantly higher activity of 86 ± 1 %. A slight increase in hemolysis was observed for SnO2 calcined at 650 °C, reaching 1.3 % at higher concentrations, but overall, hemolysis remained below 5 %, indicating high hemocompatibility.

Exploring the impact of CuCl2 modification on structural variations and dielectric constant in bismuth borate tellurite glasses

Copper chloride doped boro-tellurite-based glass series with compositions 60TeO2-(25-x) Bi2O3–15B2O3-xCuCl2 (x = 0, 5, 10, 15, and 20) were synthesized using the traditional melt-quench procedure. The X-ray diffraction patterns of the examined glasses reveal their amorphous nature. The effect of CuCl2 addition on the glass network/structural units was studied using vibrational (FTIR/Raman) spectroscopy, and CuCl2 inclusion in the glass matrix resulted in a transformation from compact TeO4 to TeO3 structural units This shows that copper chloride acts as a modifier in the examined glass series, resulting in the creation of non-bridging oxygen (NBOs), meaning that the loosening of the glass network is further supported by a decrease in the glass transition temperature as CuCl2 content increases. UV–Vis DRS spectra of examined glasses reveal an absorption band corresponding to the typical transition of Cu2+ ions from 2B1g → 2B2g, situated in deformed octahedral sites in absorption spectra. As Cu+ concentration rises, the indirect optical band gap values drop from 2.94 eV to 1.75 eV. The metallization criterion values lie between 0.383 and 0.300 suggesting that these glasses are potential candidates for nonlinear optical applications. With an increase in Cu+ concentration, the values of molar refractive index (Rm) and molar electronic polarizability αm increases from 22.412 to 26.205 and 8.894 to 10.398 respectively, which correlate with increasing dielectric constant (ε′) values as the Cu+ amount increases. Further dielectric studies reveal non-Debye-type relaxation behaviour.

Synthesis of undoped and mixed binary transition metals (Ni-Co)-doped cupric oxide nanostructures: Structural characteristics, optical behavior, and biological activity

In this work, co-precipitation-assisted undoped and various concentrations (1%, 3%, and 5%) Ni-Co-doped CuO nanostructures have been synthesized to test the biomedical applications. The structure, optical band gap, zone of inhibition width, hemocompatibility, and free radical scavenging activity of the CuO are significantly varied by introducing various concentrations of co-dopants compared to the undoped CuO. The single phase of monoclinic and heterogeneous crystal systems (monoclinic CuO, hexagonal Co, cubic NiO, and Co3O4) for undoped CuO and all Ni-Co-doped CuO samples was identified by the powder XRD tools. Microstructural properties were tuned in each dopant concentration of Ni-Co in the CuO, which confirmed through FE-SEM analysis. Heterogeneous structures (spherical particles/sheet-like particles) were noticed in the HR-TEM studies of 5% Ni-Co-doped CuO nanostructures. Synthesized compounds related to the elements (Cu, O, Co, and Ni) were traced with the help of the EDX and XPS study. The photoabsorption spectra and optical band gap values of the undoped CuO and co-doped CuO samples were significantly varied. Antimicrobial studies of the undoped CuO and Ni-Co co-doped CuO against E. coli and S. mutans bacterial strains were performed, and their outcomes of the zone of inhibition (ZOI) values have been discussed in detail. The synthesized undoped and various concentrations of CuO particles were taken to investigate their compatibility via hemolytic study. Hemolysis results showed that both the synthesized undoped CuO and Ni-Co doped CuO nanostructures are highly hemocompatible. In addition, compatibility natures are varied with increasing concentrations from 1% to 5% Ni-Co dopant in the CuO samples. The DPPH assay was employed to evaluate the antioxidant properties of the synthesized particles by determining their free radical scavenging (FRS) activity percentages. It was observed that Ni-Co-doped CuO exhibited better antioxidant properties than undoped CuO due to the higher FRS percentage.

The effect of seed layer cycles on the structural, optical, and morphological properties of ZnO nanorods.

In this study, ZnO seed layers with different cycles were formed on glass substrates by the sol-gel technique, and ZnO nanorods were grown on them by the hydrothermal method. Morphology and the structural characterization of the seed films and the ZnO nanorods are carried out by field emission scanning electron microscopy (FE-SEM) and x-ray diffraction techniques. In addition, to investigate the effect of seed layer deposition cycles on the optical properties of the ZnO nanorod arrays, UV/visible spectrophotometer and photoluminescence (PL) measurements were performed. The changes in structural and optical parameters such as dislocation density, strain, crystallite size, and optical band gap values on each seed layer deposition cycle were examined. The highest optical band gap and crystallite size were obtained for ZnO nanorods with 4 cycles seed layer as 3.22 eV and 63.6 nm, respectively. Also, in the PL spectrum, the largest ratio of UV-emission region to weak-visible emission region was obtained in ZnO nanorods having 4 cycles. In addition, the glucose detection properties of ZnO nanorods having 4 cycles were investigated using the PL measurements and it was found that UV-emission peak intensity of ZnO nanorods decreased as the glucose concentration increased from 8 to 40 mM. The results show that the number of deposition cycles of the seed layer has a strong influence on the orientation, crystal quality, and optical band gap of the growing ZnO nanorods, as well as significantly affecting their morphological properties. RESEARCH HIGHLIGHTS: High quality ZnO nanorods were grown on glass substrates by hydrothermal method. The effect of ZnO seed layer cycles on the structural, optical, and morphological characteristics of ZnO nanorods grown on were examined. It was found that the number of cycles of the seed layer is a critical parameter for growing quality and well-aligned ZnO nanorods.

Synthesis of nanoscale spinel aluminates powder and studies of their optical and structural properties

In this research, Manganese aluminate (MA), Nickel aluminate (NA), and Zinc aluminate (ZA) nanocrystallites were synthesized using the combustion method at a temperature of 1173 K. This technique was selected for its effectiveness in producing nanocrystalline materials with high purity and precise compositional control. The synthesized nanocrystallites underwent extensive characterization to understand their structural and optical properties. Techniques such as UV–visible spectrophotometry (UV–vis), Fourier-transform infrared spectroscopy (FT-IR), and x-ray diffraction (XRD) were utilized to examine the impact of different cations (Mn2+, Ni2+, Zn2+) on the optical bandgap, binding energy, and crystallographic parameters of the materials. The optical bandgap values (Eg), determined using Tauc’s formula, were 4.121 eV for manganese aluminate, 3.819 eV for nickel aluminate, and 3.771 eV for zinc aluminate. FT-IR spectroscopy identified fundamental absorption peaks within the range of 450 to 750 cm−1, confirming the formation of aluminate spinel structures. XRD analysis confirmed the presence of a cubic spinel-type structure in all three prepared samples. The results revealed that the average crystallite sizes ranged from 23.890 nm to 45.100 nm, cell volumes varied between 521.47 Å3 and 548.68 Å3, lattice constants spanned from 8.258 Å to 8.049 Å, and inter-planar spacing ranged from 2.4268 nm to 2.4532 nm. These variations were observed as the cation transitioned from nickel to manganese passing through zinc element. Additionally, Rietveld refinements were performed to further analyze and refine the crystal structures based on XRD data. This comprehensive study aimed to elucidate the relationship between the synthesis conditions and the resultant properties of the nanocrystallites, providing insights into their potential applications in fields such as optoelectronics and photocatalysis.

Phosphorus doped hydrogenated silicon oxycarbide: Film formation, properties and its application on silicon heterojunction solar cell

An ultrathin phosphorus doped hydrogenated microcrystalline silicon oxycarbide (n-μc-SiCO:H) layer deposited by plasma enhanced chemical vapor deposition (PECVD) method can be used as a window layer for silicon heterojunction solar cells. The optical and electrical properties of n-μc-SiCO:H films were controlled by PECVD deposition conditions. The interplay effects of H2, CO2 and PH3 to SiH4 gas ratio on the chemical composition, material structure and properties of n-μc-SiCO:H film were systematically determined. O, H, C and P atoms were observed to incorporate into the silicon network of n-μc-SiCO:H layer, while most of the atoms bond directly to Si atoms. Incorporation of oxygen and carbon atoms into n-μc-SiCO:H film, confirmed by XPS as formation of Si-O and Si-C bonds, enlarged the optical absorption band gap (Eg) value. Both film crystallinity and phosphorus concentration in n-μc-SiCO:H layer were observed to be controlled by the H2, CO2 and PH3 to SiH4 gas ratio. The electric performance of HJT solar cell was depended on the optical and electrical properties of n-μc-SiCO:H layer. An average efficiency (across ∼ 120 cells) of 26.32 % was achieved in cells with optimized deposition parameters for the n-μc-SiCO:H layer. The reaction gas ratio was also the dominant factor in determining the number and size of nanoscale Si crystallites embedded in the n-μc-SiCO:H layer. The conductivity of n-μc-SiCO:H layer was determined by the activated phosphorus concentration but independent of the total phosphorus concentration. It was also found that large concentrations of small Si crystallites of size less than 3 nm improved film conductivity.

Enhanced properties of TiO2 nanotubes through α-Fe2O3 surface decoration: Synthesis, characterization, and performance evaluation

Electrochemical anodization, under a constant voltage of 45 V and for 15, 30, and 45 min, was performed to fabricate highly ordered TiO2 nanotubes. Depending on the processing paramters, the diameter of the TiO2 nanotubes was found to be around 95 ± 6 nm, while the thickness of TNT layer exhibited a change with anodizing time, varying from 1 to 4 μm. Subsequent to the anodization α-Fe2O3/TiO2 heterogeneous structure was created by the spin coating of iron precursor based solutions on TiO2 nanotubes. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were utilized to ascertain the phase structure and morphology of TiO2 nanotubes. The change of optical band gap values depending on the processing parameters was calculated using UV–Vis spectrophotometer data. The photocatalytic performances of the samples, namely the degradation rates and kinetics, were evaluated by examining the photodegradation of methylene blue (MB). The (TC15) sample, obtained by anodizing for 15 min and decorated with α-Fe2O3, exhibited the highest photocatalytic activity, with a degradation efficiency of 70 % at the end of 7 h of light exposure. On the other hand, the inhibition percentages of bacterial growth were examined and it was seen that the TC30 sample with the highest value was 88.89 % for E.coli bacteria and 70.57 % for S.aureus. To assess the mechanism of antimicrobial activity, ROS (Reactive Oxygen Species) Analysis were perfomed on T30 and TC30 groups and the ROS amount of TC30 was higher than T30. According to the results of the L929 mouse fibroblast cytotoxicity experiment with indirect contact according to ISO 10993-5 standards, all samples showed a successful performance in terms of cell viability. The cell viability of TC15 was higher in comparison to the control group.

Praseodymium doping-induced band structure tunning in bismuth ferrite (Bi1-xPrxFeO3) nanofibers for the enhanced photocatalytic properties

The study investigates the influence of praseodymium (Pr) doping on bismuth ferrite (BiFeO3/BFO) nanofibers and their structural, morphological, magnetic, optical, and photocatalytic properties. A series of bismuth ferrite nanofibers with varying concentration of Pr (Bi1-xPrxFeO3, x = 0.00, 0.05, 0.10, and 0.15 mol%) were successfully synthesized using an electrospinning technique. XRD patterns revealed that structural transformation occurred from rhombohedral to orthorhombic upon effective doping of Pr3+ into BFO nanofibers. The X-ray photoelectron spectroscopy analysis confirmed that Bi, Fe, and O maintained their native oxidation states of +3 and -2, respectively in the bare and doped systems. Furthermore, the optical band gap value was significantly reduced from 2.35 to 2.22 eV as well as the recombination rates of charge carriers in the doped systems, especially in BP0.15O system. The photocatalytic performance of the prepared samples was studied by measuring the decomposition of rhodamine B (RhB) under sunlight irradiation. Outcomes showed that the doped-BFO nanofibers exhibited enhanced photocatalytic performance compared to pure BFO, with the BP0.15O system showing the 98 % degradation in 60 min. This enhancement could be attributed to the presence of Pr-energy levels, which facilitating enhanced separation, and charge transfer to the surface for the effective redox reactions.

Optimizing charge transport and band-offset in silicon heterojunction solar cells: impact of TiO2 contact deposition temperature

Carrier selective contacts are a primary requirement for fabricating silicon heterojunction solar cells (SHSCs). TiO2 is a prominent carrier selective contact in SHSCs owing to its excellent optoelectronic features such as suitable band offset, work function, and cost-effectiveness. Herein, we fabricated simple SHSCs in an Al/TiO2/p-Si/Ti/Au device configuration. Ultrathin 3 nm TiO2 layers were deposited onto a p-type silicon substrate using the atomic layer deposition method. The deposition temperature of TiO2 layers varied from 100 °C to 250 °C. X-ray photoelectron spectroscopic studies suggest that deposition temperature highly affects the chemical states of TiO2 and reduces the formation of defective state densities at the Fermi energy. The optical band gap values of TiO2 layers are also altered from 3.13 eV to 3.27 eV when the deposition temperature increases. The work function tuning from −5.13 eV to −4.83 eV has also been observed in TiO2 layers, suggesting the variation in Fermi level tuning, which arises due to changes in carrier concentrations at higher temperatures. Several device parameters, such as ideality factor, trap density, reverse saturation current density, barrier height, etc, have been quantified to comprehend the effects of deposition temperature on photovoltaic device performance. The results suggest that the deposition temperature significantly influences the charge transport and device performance. At an optimum temperature, a significant reduction in charge carrier recombination and trap state density has been observed, which helps to improve power conversion efficiency.

Exploring the optical and electric features of PMMA/PVAc blended polymers doped with TBAI/MWCNTs fillers for different applications

The present study focuses on the production of poly (methyl methacrylate)/poly (vinyl acetate)/tetrabutylammonium iodide/multi-walled carbon nanotubes (PMMA/PVAc/TBAI/x wt %MWCNTs) blended polymers. These blends show great potential for use in advanced optical, energy storage and electronics applications. X-ray diffraction (XRD) and scanning electron microscopy techniques was used to explore the structure and morphology of PMMA/PVAc/TBAI with x wt% MWCNTs blended polymers. The optical transmittance lowered to a minimum value of 53–63 % within the specific wavelength range as the blend contained 0.55 wt % multi-walled carbon nanotubes (MWCNTs). The sample containing 0.11 wt% MWCNTs demonstrated the highest reflectance (R) values, whereas the sample with 0.55 wt% MWCNTs showed the lowest R values. As the concentration of MWCNTs increased, these values consistently decreased. The smallest direct (4.55 eV) and indirect (4.45 eV and 2.48 eV) optical band gap (Eg) values were achieved when wt% of MWCNTs were 0.44 % and 0.55 %, respectively. The doped blend with wt% of 0.11 exhibited the highest refractive index values. Blend with x = 0.55 wt % MWCNTs has the highest dielectric constant. The energy density (U) increased non-uniformly as the blend was infused with MWCNTs. Elevating the temperature enhances the values of U for all blends. All blends adhered to the correlated barrier hopping (CBH) model. The effects of MWCNTs doping amount and temperature on the impedance and electric modulus of the host blend were investigated. The dc conductivity of the doped samples was observed to be greater than that of the undoped blend, except for the blend with x = 0.44, where it diminished. The undoped blend displayed activation energy (Ea) values of 1.71 eV and 0.6 eV, depending on the temperature range. When the host blend is doped with MWCNTs, the Ea values either rise or fall depending on the quantity of MWCNTs. All samples have non-ohmic characteristics.

Exploring the anticancer potential of novel chalcone derivatives: Synthesis, characterization, computational analysis, and biological evaluation against breast cancer

This study presents a detailed synthesis and in-depth structural analysis of chalcone compounds with putative anticancer activity. The synthesis procedure for (2E)-1-(2,4-dichlorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one (MLDCL), (2E)-1-(4-fluorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one(MLFC) and (2E)-3-(4-methylphenyl)-1-(4-nitrophenyl) prop‑2-en-1-one (MLNC) involves Claisen-Schmidt condensation reaction. Modern analytical methods like FT-IR and H1 NMR spectroscopy were performed for structural characterization and accurate determination of chalcone compounds in the study. Using a UV–Vis-NIR spectrometer, the linear absorption spectra of three crystals were determined. The optical band gap (Eg) value of these chalcones is acquired from the tauc's plot of (αhv)2/3 against (hv). The in silico molecular docking with protein 3EQM provided valuable insights into potential interactions with the created compounds, yielding docking scores ranging from -8.8 to -7.8. Specific amino acid residues, such as ALA438, ALA306, and ILE133, were implicated in these interactions. The top-ranked compound MLNC (TOP1) from docking was further deemed for molecular dynamics studies, MTT assay, apoptosis, and cell cycle studies. The structural dynamics and stability of protein complexes 3EQM-APO, 3EQM-ASD (standard), and 3EQM-TOP1 were assessed over a 300 ns simulation period. Molecular dynamics studies showed that the complex was stable for a complete 300 ns. MTT assay was performed on triple-negative breast cancer cell line MDMAB-231 and normal fibroblast L929 cell line. An apoptosis and cell cycle studies were performed to further confirm the anti-cancer activity of the top-ranked compound MLNC.