Optical Band Gap Energy Research Articles

Studies of Structural and Optical Properties of Nickel Chloride and Glycine Doped Potassium Hydrogen Phthalate (KHP) Crystal

A semi-organic single crystal of potassium hydrogen phthalate (KHP, K(C6H4COOH.COO)) doped with Nickel Chloride (NiCl2) and Glycine (C₂H₅NO₂) was successfully harvested at room temperature to enhance the characteristics of KHP using a slow evaporation approach. The concentration of 1 mol % of Nickel Chloride and 6 mol % Glycine was used during the fabrication of the Nickel Chloride and Glycine doped KHP single crystal. Powder X-Ray diffraction (XRD), ultraviolet visible spectroscopy (UV-Vis), and Fourier transform Infrared (FTIR) analysis were used to analyze the grown single crystal. Powder XRD investigation verified an orthorhombic crystal structure and lattice parameter .To evaluate optical energy band gap and optical transparency using UV-Vis spectral. According to, FTIR analysis, and dielectric studies, it is evident that the crystal modification noticeably by adding dopant.

Gadolinium doped lithium aluminum borate [Li3Al3(BO3)4:Gd] materials synthesized and characterized for its structural, optical and thermoluminescence properties for use in dosimetric application

Lithium aluminum borate materials was made ready for dosimetric uses in radiation processes. In order to enhance the structural and dosimetric qualities, varying mole concentrations of gadolinium were added to samples of lithium aluminum borate materials. High temperature solid-state technique was used in producing the lithium aluminum borate material. The characterization of the material was archived by using Scanning electron microscope, X-ray diffractometer, thermal gravimetric evaluation, UV-vis-NIR spectrophotometer and thermoluminescence reader/irradiator in other to determine for their structural, thermal analysis, optical properties and dosimetric properties respectively. The kinetic analysis of the major glow peak yielded the activation energy. The crystalline sizes of the undoped and gadolinium-doped Li3Al3(BO3)4 materials were reported to be approximately 36.38 nm and 68.84 nm, respectively, which relies on their matching peaks at a 2θ angle of 25.79o. The grain size for the undoped and gadolinium doped lithium aluminum borate were found within a given range of values 140 – 160 nm, and 80 – 100 nm respectively. The optical energy band gap was found within 3.90 eV to 4.35 eV for the gadolinium doped while the undoped is 3.00 eV for lithium aluminum borate respectively. A larger energy band gap of lithium aluminum borate was observed after gadolinium was incorporated as dopant. The phosphor of lithium aluminum borate doped with gadolinium was observed to exhibit prominent TL intensity peaks at 100 oC following irradiation. The irradiated samples of lithium aluminum borate doped with gadolinium showed a dose response that was linear between 20 and 150 Gy. This work demonstrates the potential use of Gd-doped lithium aluminum borate phosphor in radiation dosimetry.

Holmium ions influence in structural and optical properties of Aluminium Strontium-phosphate glasses for radiation shielding applications

This study details the synthesis of a novel series of Holmium-doped Aluminium Strontium-phosphate glass (HoAlSr- phosphate glass) composed of 55 P2O5 + 5 Al2O3 + 4 MgO + 5 NaF + 10 LiCO3 + 5 CaO + 10 SrCO3 + 5 ZnO + 1 Ho2O3 prepared by melt-quench method and its structural, optical, and physical properties are analysed. Powder −XRD verified its amorphous nature, FTIR shows the existence of large phosphate functional groups, Optical properties such as band gap energy was calculated by acquiring absorption spectra covering the UV, Vis, and NIR ranges. Obtained 3.02 eV optical band gap energy. The refractive index changing with increasing energy. Three peaks in the PL spectra corresponded to Ho3+ transitions: 5I8→ 5G6, 5I8→ 3K8, and 5I8→ 5F3. The glass conducted theoretical studies for radiation shielding properties based on several key parameters. Gamma radiation shielding parameters, including Mean Free path (MFP), Effective atomic number (Zeff), linear attenuation coefficient (LAC), and mass attenuation coefficient (MAC), were obtained with the use of the Phy-X program. MAC data show that when Compton scattering (CS) fluctuates in the intermediate photon energy zone (E > 3 MeV), the area of prominence of CS diminishes. They can cause pair production at higher energies, Compton scattering at intermediate energies, and the photoelectric effect at lower energies. The MFP values of glasses doped with HoAlSr- phosphate glass were shorter, indicating a higher level of shielding efficacy. In this study we are focusing on optical properties changes with presence of Holmium ions and its shielding property using Phy-x software. In this research discovered that the synthetic material has high shielding qualities and can be a valuable shield in environments where X-rays are present. So it will be beneficial at X-ray prompted environment

Sustainable non-volatile resistive switching memory using chitosan/MEH-PPV polymer blend

Functionalisation of materials is crucial in modern science and technology, particularly biodegradable ones, to reduce the increasing electronic waste affecting the planet. In this study, the electronic behaviour of chitosan was modified by incorporating the MEH-PPV polymer. Four composites with weight percentages of 0.25 (S1), 0.5 (S2), 1 (S3), and 1.5 (S4) wt% were prepared. The optical energy bandgap of these composites ranged from 2.0 to 3.02 eV. These materials were studied for their potential use in resistive switching memory (ReRAM). Two device classes: Class A (drop cast) and Class B (spin coat), were developed. The Class A S4-based device exhibited memory behaviour with a minimum of 20 write/erase cycles. The other devices in this class demonstrated poor conductivity and data noise. Class B devices exhibited no switching, except for the S3-based device. This research suggests that the thickness of class A devices has a notable impact on their performance limitations. The study shows that the chitosan:MEH-PPV blend holds promise for environment-friendly ReRAMs, and optimizing the thickness and weight ratio can significantly improve device performance.

Advanced spectroscopic approach for exploring the structural, optical, and electronic properties in dye-functionalized chitosan biopolymers

This study employed advanced spectroscopic techniques to investigate the structural and optical properties of chitosan (CS) biopolymer films modified with natural dyes from Cosmos Sulphureus Cav. (CSC) flowers. FTIR results indicated that the inclusion of CSC dyes led to broader absorbance and decreased transmittance. Distinct absorption regions were identified, and the optical energy band gap (OEBG), transport gap, and exciton binding energy were calculated using Tauc’s method. The OEBG was found to be 5.44 eV for CS while for CS-CSC dye samples, it dropped to 2.24 eV and The Urbach energy increased from 0.44 eV to 0.60 eV, indicating the presence of high tail states in the band gap region. The electron–phonon interaction was found to increase from 11.35 to 15.58. The oscillator energy values (4.13 eV-2.33 eV) at low energies obtained using Wemple-DiDomenico model are found to be close to OEBGs using Tauc’s model. Additionally, from the Drude-Lorentz model the N/m* was found to increase from 1.69 × 1052 to 1.27 × 1054. The third order non-linear polarizability parameter, the linear optical susceptibility and the non-linear index of refractions were all found to increase upon increasing the CSC dye concentrations.

Synthesis, Spectral Characterization, Antimicrobial Activity, DFT Calculations, Molecular Docking and ADME Studies of Novel Schiff Base Co(II), Ni(II), Cu(II) and Zn(II) Complexes Derived from 4-nitro-ortho-phenylenediamine.

A condensation reaction was carried out between 4-nitro-ortho-phenylenediamine and 5-bromosalicyaldehyde to synthesize a novel Schiff base ligand 2,2'-[(1E,1'E)-(4-nitro-1,2-phenylene) bis (azaneylylidene) bis (methaneylylidene)] bis (4-bromophenol) [NB] in the current investigation. This was followed by the synthesis of metallic complexes comprising the Co(II), Ni(II), Cu(II) and Zn(II) transition metal ions. A hexadentate environment encircling metal complexes was corroborated by the results of varied spectroscopic methods that were employed to unravel the structure of the ligand and metal complexes. The Tauc's plot and Urbach energy were utilized for quantifying the optical energy band gap to provide insight into optical characteristics. The Coats-Redfern method of thermal analysis was implemented to do the kinetic and thermodynamic calculations. Furthermore, DFT studies were performed to predict geometrical structures and the stability of the compounds. Thorough investigation to evaluate their biological efficacies, docking studies was executed against COVID-19 main protease (PDB-7VAH), Dengue virus NS2B/NS3 protease (PDB-2FOM) and Mycobacterium Tuberculosis (PDB-5AF3). Apart from this, in silico ADMET studies were also accomplished for elucidation of drug likeness characteristics and the results attained disclose the significant proficiency of synthesized compounds. Besides this, antimicrobial studies were assessed with different microbial strains and result validates cobalt and zinc complexes as most potent against the selected bacterial and fungal strains.

Fabrication and characterization of PVDF/PMMA nanocomposite membranes doped with graphene oxide (GO) for separation of CO2/CH4 from flue gas

This work focuses on developing polyvinylidene fluoride/polymethyl methacrylate (PVDF/PMMA) polymer blend nanocomposites incorporating varying concentrations of graphene oxide (GO) nanoparticles fabricated via casting solution processes. XRD and FT-IR confirmed GO-induced structural modifications in PVDF/PMMA blend. The addition of GO into PMMA/PVDF blend decreased and weakened the intensity of XRD peaks, suggesting that adding GO gradually reduces the crystallinity of the films. FT-IR verified miscibility and complex formation between the pristine polymer blend and the GO-filled nanocomposite. The incorporation of GO caused shifts in the optical absorption edge to lower wavelengths, causing a decrease in the optical bandgap energy (Eg). The real and imaginary parts of the dielectric permittivity (ε′ and ε′′), electric modulus (M′, M″), and AC conductivity (σac) have been measured from 0.1 Hz to 6 MHz. Both ε′ and ε′′ declined with rising frequency. The addition of different concentrations of GO generated charge transfer complexes in the polymer nanocomposites. SEM images show good homogeny with random dispersion of GO inside the polymer blend. The thermoluminescence (TL) glow curves for the nanocomposite samples irradiated 0.5, 1.0, 1.5, and 2 Gy doses show peak cantered at 207 °C. The peak position remained unchanged with increasing irradiation dosage. The dose-dependent linear growth in maximum peak height indicates radiation detection and monitoring capability.

Facile green synthesis of ZnO/ZrO2 nanocomposite for photocatalytic degradation and chromium (VI) reduction

In the field of nanoscience, using plant materials to create nanoparticles (NPs) is becoming growing in popularity and offers a number of benefits over physicochemical techniques. The green combustion approach effectively synthesized ZnO/ZrO2 nanocomposite (NCs) using powdered Butea monosperma (BM) leaf as the green fuel. The nature of NCs was confirmed through (X-ray Diffraction) XRD revealed that presence of hexagonal ZnO and cubic of ZrO2 phase. The morphology of NCs as seen by (Scanning Electron Microscopy) SEM and (Transmission Electron Microscopy) TEM reveals a fair distribution and non-uniform spherical shape. (Energy Dispersive X-Ray Analysis) EDAX pattern indicates the presence of zinc, zirconium and oxygen components. (Fourier Transform Infrared Spectroscopy) FT-IR spectrum obtained the metal–oxygen bonding in NCs. By applying the Tauc relation to calculate the optical energy band gap value of the sample is3.34 eV. UV light is used to conduct theinvestigation ofphotocatalyticdegradation of methylene blue (MB) dye. The NCs have superior degradation efficiency up to 99 % dye degradation is performed in 150 min. Furthermore, NCs exhibit a hazardous chromium (VI) decrease of up to 62 %. The collected results demonstrated that ZnO/ZrO2 NCs are the best photocatalyst for MB degradation and chromium reduction.

Comprehensive perspectives: fabrication, luminescence, and in-vitro properties of Tm3+-doped SrS

ABSTRACT In this study, the Tm3+-doped SrS samples were synthesised using the sol–gel method and investigated their luminescence and in-vitro characteristics. The structural analysis confirmed the monoclinic crystalline structure, with evident incorporation of Tm3+ ions into the SrS lattice. Optical band gap energies were determined to be in the range of 3.94–4.05 eV. Photoluminescence (PL) measurements revealed visible red emission (around 640 nm) originating from the1G4 → 3F4 transition of Tm3+ ions within the SrS lattice. In-vitro analysis demonstrated enhanced hemocompatibility resulting from thulium doping. The biocompatibility, combined with visible emission characteristics, indicates promising applications in bioimaging. This research sheds light on the synthesis and characterisation of Tm3+-doped SrS samples, highlighting their potential for bioimaging and other related fields.

Novel synthesis of reduced PdO-WO3 hybrids for enhanced photoelectrochemical water splitting

In this study, a novel synthesis approach for WO3 nanoparticles and their hybrids is proposed, followed by an investigation of their photoelectrochemical performance for water splitting applications. The surface modification of WO3 nanoparticles is carried out by immersing them in a Pd precursor solution, followed by calcination to obtain PdO-WO3 hybrid nanoparticles. Subsequently, the PdO-WO3 is reduced in a hydrogen (H2) environment to prepare PdOx-WO3-y hybrid material. XPS analysis revealed that H2 reduction converts residual metallic Pd to PdH and simultaneously generates oxygen vacancy defects in WO3 hybrid nanoparticles, as confirmed by EPR analysis. Additionally, TPR analysis further confirms the H2-induced reduction in the PdO-WO3 hybrid at a lowered temperature of 150 °C. The optical band gap energy of PdOx-WO3-y hybrid nanoparticles is slightly reduced (by 0.06 eV) compared to that of the PdO-WO3 reference sample. Photoelectrochemical measurements were conducted to assess the impact of these tailored modifications on the performance of conventional PdO-WO3 nanoparticles. The reduced PdOx-WO3-y catalyst exhibits an approximatly ∼22 % improvement in incident photon-to-current conversion efficiency (IPCE), over the unreduced PdO-WO3. The PEC efficiency improvement was attributed to the composite electronic structure changes introduced during the annealing process. Mott-Schottky measurements confirm that the reductive treatment consolidates the material’s two distinct flat band potentials (Efb) into with a single intermediate energy level and increases the charge carrier concentration. This study presents a straightforward method to generate oxygen vacancy defects in hybrid metal oxides and provides a convenient method for band gap engineering for photoelectrocatalytic applications.

Biofabrication and Characterisation of Ni‐Doped SnO2 Nanoparticles With Enhanced Cytotoxicity, Antioxidant, Antimicrobial and Photocatalytic Activities

ABSTRACTThe present work focuses on Annona muricata leaf extract–mediated green synthesis of pure and nickel‐doped tin oxide nanoparticles for 3%, 5% and 7% concentrations. The properties of the obtained nanoparticles were investigated through XRD, FTIR, XPS, HRTEM–SAED, SEM–EDX and UV–visible spectroscopy techniques. The XRD pattern reveals all samples have tetragonal structures with high crystallinity. The Sn–O stretching vibration has been confirmed through FTIR spectra. The XPS results demonstrate that Sn0.93Ni0.07O2 nanoparticles have Sn3d, Ni2p and O1s oxidation states. EDX spectra contain Ni, Sn and O elements, which indicate the purity of the samples. UV–visible absorption spectrum shows decreases in optical energy bandgap with increases in nickel dopant concentration. The samples exhibit notable antibacterial activity against P. aeruginosa and S. aureus. Also, Sn0.93Ni0.07O2 nanoparticle has higher antifungal activity against A. niger than against C. albicans. Moreover, SnO2 nanoparticles have considerable antioxidant activity in DPPH scavenging compared to Sn0.93Ni0.07O2 nanoparticles. Furthermore, SnO2 nanoparticles have a better cytotoxic effect for L929 normal fibroblast cell lines with an LD50 value of 146.42 μg/mL. Additionally, the photocatalytic activity of SnO2 and Sn0.93Ni0.07O2 nanoparticles was done against methylene blue dye under direct sunlight irradiation. Overall, environmentally friendly synthetic pure and Ni‐doped SnO2 nanoparticles can be used in wastewater filter technologies as well as in medical aids due to their better cytotoxic, antioxidant and antimicrobial effects.

A DFT study on the role of excitons and electric field-induced symmetry breaking and topological properties of ZrBr

The control of band gap and topological properties is a crucial objective in the field of materials science, particularly for the application of 2D materials such as topological insulators. Zirconium monobromide (ZrBr), a topological insulator with band inversion, holds significant potential for various applications. In this study, we used Density Functional Theory (DFT) with different approximations namely, Generalized Gradient Approximation (GGA) with and without spin orbit coupling (SOC) as well as hybrid functional to investigate the electronic structure and the band gap of this compound. In addition, we introduced the excitonic effect by considering GW plus Bethe–Salpeter equation (GW-BSE) to compute the optical band gap and quasi-particle energy. We found that ZrBr present a low static dielectric function and weak exciton binding energy, generally lower than those of conventional semiconductors. This behavior is due to the reduced Coulomb interaction in the material. To further explore the material’s behavior, we apply an electric field in three directions to observe symmetry breaking and its impact on band gap tuning. This comprehensive analysis aims to explore the understanding and the potential applications of ZrBr as a topological insulator.

Biofabrication, characterization and unveiling the biological potential of zinc oxide nanoparticles from bacterium Bacillus pacificus KR A1

The utilization of cell free supernatant for synthesizing nanomaterials has been considered as an innovative approach. This investigation aims to fabricate a ZnO NPs using the cell free supernatant of Bacillus pacificus KR A1. The prepared nanomaterials were systematically characterized by UV-DRS, FT-IR, XRD, HR-TEM, XPS and elemental mapping (EDX) techniques. The optical band gap energy of Bacillus pacificus ZnO NPs (Bp-ZnO NPs) was observed as 3.25 eV. The XRD analysis revealed that Bp-ZnO NPs were hexagonal wurtzite structures with 50 nm crystallite size. Furthermore, XPS data revealed the elements present in Bp-ZnO NPs. The HR-TEM analysis revealed that most of the particles were spherical in shape with an average calculated particle size of 20 nm with a lattice fringe range of 0.246 nm. In addition, Bp-ZnO NPs showed promising antibiofilm properties against Bacillus cereus and Vibrio alginolyticus at 100 μg/mL concentration. Furthermore, MDA-MB-231 cells treated with an IC50 concentration showed changes in cell morphology including apoptosis, cell shrinkage and nuclear fragmentation. However, HUVEC cells treated with higher concentration (40 µg/mL) of Bp-ZnO NPs displayed less toxicity and 86.3 % of cells are viable. In summary, Bp-ZnO NPs could serve as a promising material for biomedical claims.

Nanocomposite superstructure of zinc oxide mesocrystal/reduced graphene oxide with effective photoconductivity

Metal oxide mesocrystals are the alignment of metal oxide nanoparticles building blocks into the ordered superstructure, which have potentially tunable optical, electronic, and electrical properties suitable for practical applications. Herein, we report an effective method for synthesizing mesocrystal zinc oxide nanorods (ZnONRs). The crystal, surface, and internal structures of the zinc oxide mesocrystals were fully characterized. Mesocrystal zinc oxide nanorods/reduced graphene oxide (ZnONRs/rGO) nanocomposite superstructure were synthesized also using the hydrothermal method. The crystal, surface, chemical, and internal structures of the ZnONRs/rGO nanocomposite superstructure were also fully characterized. The optical absorption coefficient, bandgap energy, band structure, and electrical conductivity of the ZnONRs/rGO nanocomposite superstructure were investigated to understand its optoelectronic and electrical properties. Finally, the photoconductivity of the ZnONRs/rGO nanocomposite superstructure was explored to find the possibilities of using this nanocomposite superstructure for ultraviolet (UV) photodetection applications. Finally, we concluded that the ZnONRs/rGO nanocomposite superstructure has high UV sensitivity and is suitable for UV detector applications.

Synthesis and characterization of erbium silica glass and glass-ceramics for potential low-emissivity coating applications

Silica glasses co-doped with varying concentrations of Er3+ (0.8, 1.5, 4, and 8 mol %) were fabricated employing the sol-gel technique. The effects of erbium concentration were evaluated through several characterization techniques, including X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV–visible transmission spectroscopy, and photoluminescence analysis. The incorporation of erbium ions significantly altered the structural, optical, and photoluminescence properties of the doped glasses. XRD analysis revealed the presence of SiO2 in both tetragonal and hexagonal forms, along with Er2SiO5 crystalline phases. SEM images showed irregular rod-shaped structures with agglomeration and micro-flake cubic shapes. FTIR spectroscopy provided insights into the structural characteristics of the materials. Notably, the optical band gap energy of the glassy films increased, accompanied by fluctuating Urbach energy and a slight reduction in the refractive index, attributed to structural changes within the glass network. Photoluminescence spectra indicated strong emissions at 523 and 543 nm, corresponding to the transitions 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2, respectively. Additionally, a notable near-infrared emission at 1532 nm was observed, linked to the transition 4I13/2 → 4I15/2. The color coordinates of the produced glasses were found to be near the green or yellow regions, suggesting potential applications in optical amplifiers, lasers, and low-emissivity coatings.

Green biogenic synthesis of magnetite nanoparticles from indigenous Banksia Ashbyi leaf for enhanced sonochemical dye degradation

Abstract Developing alternative green and sustainable technologies to prevent, reduce, and remove toxic dyes present in effluent generated by the textile industry is of global importance. In this study, magnetite (Fe3O4) nanoparticles (MNPs) were successfully synthesized using a co-precipitation method that used Indigenous Banksia Ashbyi (BA) leaf extract in varying amounts (BA-MNP 1 to BA-MNP 4), to modulate particle size and size distribution. The formation of the MNPs was confirmed by a range of characterization techniques that included UV–visible spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD) spectroscopy, thermo-gravimetric analysis (TGA) and scanning (FIBSEM) and high-resolution transmission (HRTEM) electron microscopy. The presence of the Fe–O bond located at 551 cm−1 in the FTIR spectra and XRD analysis of the samples confirmed the formation of crystalline MNPs. FIBSEM and HRTEM images of the BA-MNP 4 sample confirmed the MNPs were spherical (18 ± 5 nm) and tended to agglomerate. Moreover, UV–visible spectrophotometry revealed a board absorption band and an optical band-gap energy of 2.65 eV. The catalytic activity of BA-MNP 4 samples towards the degradation of a commercially available navy-blue RIT dye (BRD) were investigated under three operational senarios: 1) ultrasonic irradiation (US) + BRD; 2) BA-MNP 4 + BRD, and 3) US + BRD + BA-MNP 4. The investigation found there was an additive effect when US (80 W) was used in conjunction with BA-MNP 4 s during the dye degradation process. With no US, the BA-MNP 4 sample only achieved a dye degradation of 52% in 25 min. However, over the same period of time with US, the BA-MNP 4 sample achieved a dye degradation of 89.92%. In addition, kinetic modelling found the combined US and BA-MNP 4 process followed a pseudo-first-order kinetic model.

The Extraction of Alcea Rosea Organic Dye and Its Characterization of Optical Properties

In the present study, the optical properties of a natural dye extracted from Alcea rosea flowers were investigated. The color extraction procedure was performed using a nontoxic solvent ethanol to enhance human safety and the ecological framework. Fourier transform infrared spectroscopy was employed to determine the functional groups of the natural dye obtained from Alcea rosea flowers. The optical properties of dye were achieved by the directed thin film using UV-Vis spectroscopy and analyzed absorption spectra, coefficients, refractive indices, extinction coefficients, and optical energy bandgap. A broad absorption band occurs over an extensive waveband with peak at 380 nm. The occurrence of a low indirect bandgap in a thin film was discerned at 3.9 eV, with Urbach energy noticed in a state of 0.23 eV.

Investigating the influence of RF power on the surface morphological and optical properties of sputtered TiO2 thin films

Thin films of titanium dioxide (TiO2), with thicknesses ranging from 105 to 231 nm, were deposited on glass substrates using radio-frequency (RF) magnetron sputtering in an argon atmosphere at four distinct RF power levels: 40, 70, 100, and 130 W, with the deposition time kept constant. The crystalline structure, surface morphology and optical and semiconductor properties of the obtained films were analyzed using X-ray diffraction (XRD), Atomic Force Microscopy (AFM) and UV–visible transmittance spectroscopy. These analyses revealed that the crystallinity of the films improves with increasing RF power, corresponding to an increase in film thickness. Consequently, the samples transition from poorly crystalline or amorphous structure to a monocrystalline rutile phase with a (110) texture. However, at the highest RF power studied, this texture is partially disrupted by the formation of nanocrystals with different orientations. The surface roughness exhibited multifractal characteristics, with complexity systematically decreasing and surface stiffness reducing as RF power increased. Refractive indices and optical band gap energies were determined using the Swanepoel and Tauc plot methods, respectively. The films exhibited a notable increase in the refractive index and a decrease in the optical band gap, from 3.81 eV to 3.52 eV, as the RF power was increased. This underscores the influence of RF power on the optical and semiconductor properties of TiO2 films.

Micro structures, Morphology and Optical Properties of Sb2O3: WO3, In2O3 Nanostructure Composite Thin Films

This work is concerned with the synthesis of two types of composites thin films (Sb2O3:WO3 and (Sb2O3:In2O3) with different concentrations (0.0,0.05,0.1, and 0.15). The prepared thin films are characterized with the use of the X-ray diffraction atomic force microscope AFM and UV-Vis–infrared spectrophotometer. The structural examination shows that both composite's thin films were polycrystalline with nano size with cubic phase as majority and orthorhombic phase as minority phase. The crystal size decreases from 34.6 to 24.7 and 21.7 nm for (Sb2O3:WO3) and (Sb2O3:In2O3) thin films, respectively. The average roughness shows non-regular growth by increasing the concentration of both oxides. The optical energy band gap shows a red shift for both types of nanostructure thin films, which populate these composited thin films for solar cell applications.

Electrochemical Applications Reveal Enhanced Photocatalytic Performance of TiO2-Doped ZnS Nanocomposites.

The titanium dioxide (TiO2) nanoparticles were prepared by hydrothermal methods at ambient temperature. Based on XRD analysis, the average crystallite size of pure TiO2 nanoparticles and those doped with ZnS was calculated to be 58 and 54 nm, respectively. At an angle of 25.4°, the prominent peak observed at the (101) plane of TiO2 was confirmed. As can be seen from the collection of peaks, the TiO2 formed has an anatase-type tetragonal crystal structure. A strain of -6.4541 × 10-4 and a grain size of 33 nm can be seen in the W-H plot for TiO2 nanoparticles. For doped ZnS nanoparticles, on the other hand, the values are 1.9448 × 10-4 and 47 nm. In our study, we found that doped nanoparticles were average grain size 134 nm, while pure nanoparticles were average grain size 146 nm. Doping reduces the size of the nanomaterial, which means that the TiO2 molecules form nanoclusters on their surfaces, which can lead to a larger grain size for a pure nanoparticle than for a doped nanoparticle. A wide range of functional groups and their associated bonds were investigated using FTIR spectra in synthesized nanomaterials. TiOTi bonds are subjected to a strong stretching vibration, which is confirmed by the absorption peaks from 450 cm-1 to 800 cm-1. The PL spectra for pure TiO2- and ZnS-doped TiO2 containing nanocomposites of ZnS emit ultraviolet light at wavelengths of 362 and 379 nm in the UV region. Pure and doped samples with optical bandgap energies of ~3.04 and ~3.8 eV corresponding to anatase phases were near ~3.18 eV in Tauc plots. Since the TiO2-doped ZnS heterojunction migrates photoexcited holes toward the interface, while electrons migrate toward the bulk, this results in photoexcited holes migrating toward the interface. To calculate the specific capacitance of the synthesized materials, cyclic voltammetry with pure ZnS and those with ZnS-doped had specific capacitance values of 144.91 F/g and 120.11 F/g, respectively. The catalysts used were ZnS nanocomposite doped with TiO2 in addition to pure TiO2 nanoparticles. The degradation of dye within 80 min after sunlight exposure was monitored with a UV-Vis spectrophotometer at 20-min intervals. ZnS nanoparticles doped with TiO2 display 87.8% greater efficiency than pure nanoparticles. Doped TiO2 nanocomposite degrades at an 87.8% rate, whereas pure TiO2 degrades at ~54%, indicating that the dopants enhance photocatalysis.