Visible Region Research Articles

Structural Properties of Al-Li-Zn Borate Glass Activated with Dysprosium (Dy3+) for Radiation Dosimeter

This study explores the properties of Al-Li-Zn glass doped with dysprosium ions as a potential radiation dosimeter. The glass was prepared using the novel quenching technique, and various characterisations were performed to evaluate its properties. X-ray diffraction (XRD) analysis confirmed the amorphous phases in the glass. UV-vis spectroscopy revealed a noticeable absorption peak in the visible region, characteristic of the dysprosium ions. PL spectra luminous peaks at 348 nm (yellow), 529 nm (green), and 625 nm (orange hue), which corresponded to the 4H15/2 → 6P7/2, 4F9/2 → 6H15/2, 4F9/2 → 6H15/2, and 4F9/2 → 6H13/2 transitions in 1.5 and 2.5 dysprosium ions respectively. Significant decrease in Tg from 257°C in the undoped sample to 101°C in the doped sample, Tm of the doped sample dropped from 862°C to 815°C and Tc of the doped sample dropped from 756°C to 444°C, suggesting a reduced crystallisation threshold. FTIR analysis demonstrated that OH groups displayed peaks within the 2200 to 4000 cm range. Stretching vibrations of BO3 units occurred between 1200 and 1600. Stretching vibrations of BO4 units were observed between 800 and 1200; these show that the presence of Dy3+ and zinc oxide altered the arrangement of the glass structure, causing a transformation from B03 groups to B04 groups. This transformation leads to defects in a stable trap environment suitable for thermoluminescence phenomena. Considering its properties and optical characteristics, the samples with 1.5 and 2.5 mol % of Dy3+ showed remarkable thermoluminescence properties, suggesting its suitable use as a dosimeter to gauge radiation exposure. The glass demonstrates stability and absorption capability, making it worth considering for radiation detection applications.

Biosynthesis of Iron Oxide Nanoparticles by Fungi Beauveria Bassiania and Study of their Structural and Optical Properties

Iron oxide nanoparticles were synthesized using a biological approach using the Beauveria bassiana fungus. The synthesized nanoparticles were characterized using X-ray diffraction (XRD), scanning analysis (SEM), and atomic energy microscope (AFM). The iron nanoparticles in an average grain size of ~ 39 nm. The topography and features of the surface show that there are ripples distributed regularly and homogeneously on the surface and that the deposited film is regular. The optical properties of iron oxide were studied using UV/Vis spectroscopy, and it was found that the absorbance gradually decreases as we approach the visible light region, starting from its peak at short wavelengths, where the surface plasmon resonance was recorded, which showed the absorbance at the UV wavelength at (282 nm), and the absorbance is at its maximum at high energies (short wavelengths), then decreases with increasing wavelength to reach its lowest value in the visible region of the spectrum, and for this reason the absorbance decreases with increasing wavelength, where the energy gap value is (2.5 electron volts). The FTIR spectrum showed functional groups have been recorded in a range These results confirm the presence of the fungal extract belonging to the fungus Beauveria bassiana. The vibrations in the phenolic compounds are responsible for the interaction process with the salts of the basic materials used in the preparation

Optical Study on Co-Sensitization of Betanin Dye with Cadmium Sulfide to Fabricate Dye Sensitized Solar Cell

Natural dyes are low-cost, eco-friendly, readily available and have optical characteristics which render them useful in energy research. The titanium tetra isopropoxide precursor can be employed using sol-gel synthesis to get titanium dioxide nanoparticles (TiO2 NPs). The FESEM analysis confirmed the deposition of TiO2 NPs on Indium Tin Oxide (ITO) substrate, which is necessary for the photo-conversion mechanism to produce electricity. One of the natural dyes that is extracted from red beets is known as betanin dye (Bd). Due to their aligned energy levels, Bd and cadmium sulfide (CdS) are used together to provide effective optical characteristics, making them suitable as dye sensitizers. The presence of Cd-S, C-N and hydroxyl groups assigned to 500, 1633, and 3300 cm-1 respectively, was demonstrated by the FTIR analysis. The energy gap of 2.16, 2.13 and 2.2 eV for Bd, CdS and Bd-CdS composite was estimated using Tauc's plot and UV-visible spectra demonstrated maximum absorbance at 485, 510 and 528 nm, respectively. The Bd absorbs broad light in visible region due to the addition of CdS. The major charge-transport phenomenon in dye-sensitized solar cells (DSSC) involves an increase in photo-current density, due to its luminous nature. However, the recombination of charge carriers prevents the overall performance of the DSSCs. The power conversion efficiency of the DSSC constructed from Bd dye and Bd-CdS composite was 0.234% and 0.367%, respectively. This optical investigation suggests co-sensitization as a sure-fire method to improve the efficiency of DSSCs extracted from natural dyes, making them reliable for future indoor applications.

Ratiometric optical temperature sensing properties based on up-conversion luminescence of novel NaLaTi2O6:Yb3+,Er3+/Ho3+ phosphors

To satisfy the increasing necessity of contactless optical thermometry, utilizing both thermally coupled (TCLs) or non-thermally-coupled (NTCLs) energy levels of rare earth ions in novel phosphors has significant potential for devising the optical thermometers with high temperature sensitivity. Herein, a sequence of novel Yb3+,Er3+/Ho3+ doped NaLaTi2O6 (NLTO) phosphors were sintered using a high-temperature solid-state reaction approach. Structure, phase component and luminescence performance were identified in detail. Upon 980 nm near-infrared (NIR) excitation, the obtained materials presented typical Er3+/Ho3+ characteristic emission wavelengths in visible region, which include two green emission bands around 522 and 543 nm, as well as a weaker red band around 661 nm for Er3+ doped NLTO, a green emission band around 545 nm and a red band around 657 nm for Ho3+ doped NLTO. Besides, a unusual emission band around 757 nm of Ho3+ in visible edge region was also clearly found. The temperature sensing properties of representative NLTO:Yb3+,Er3+/Ho3+ samples were assessed based on the fluorescence intensity ratio (FIR) technique of TCLs or NTCLs energy levels. The maximal absolute sensitivity (Sa) and relative sensitivity (Sr) were determined to be 0.0374 K-1 (293 K) and 0.970% K-1 (293 K) by taking the FIR of NTCLs 2H11/2→4I15/2 and 4F9/2→4I15/2 transitions in NLTO:Yb3+,Er3+. Simultaneously, the maximal Sa and Sr were 0.0306 K-1 (573 K) and 0.776% K-1 (373 K) using the FIR of NTCLs 5F5→5I8 and 5F4,5S2→5I7 transitions in NLTO:Yb3+,Ho3+. Consequently, the temperature sensitivities above can be compared to reported results, which indicate that as-prepared materials have a promising application in optical temperature sensors field.

Ultraviolet-cured polyurea-polyurethane acrylate/polysiloxane hybrid anti-fouling coatings with superior mechanical properties, transparency, and durability

The demand for rapidly preparing omniphobic liquid-like anti-fouling coatings has become increasingly important across a wide range of applications. However, achieving a rapid fabrication process that results in coatings with effective anti-fouling properties, alongside the comprehensive performance of the coatings such as hardness, flexibility, transparency, and abrasion resistance, remains a significant challenge. Herein, this paper proposes a synergistic strategy combining ultraviolet (UV) curing and organic/inorganic hybridization, which involves the rapid cross-linking of hyperbranched methacryloxypropyl polysiloxanes (HMO), polyurea-polyurethanes acrylate (SPUA) and bis-vinyl terminated polydimethylsiloxanes (PDMS-bvt) containing multiple double bonds under UV curing for just 60 s. Notably, HMO imparts excellent hardness (7H) and abrasion resistance, while SPUA enhances the coating's flexibility (2 mm bending diameter) and adhesion (5B). The anti-fouling properties of the coating are attributed to PDMS-bvt, which provides self-cleaning, anti-graffiti, and anti-fingerprint capabilities. Additionally, the coating's hydrophobicity and smooth surface significantly reduce ice adhesion strength (21.13 ± 6.9 kPa), offering a passive anti-icing effect. Furthermore, the coating exhibits excellent transparency, with a transmittance of >92 % in the visible region. The coating exhibits remarkable durability, maintaining its anti-fouling performance after exposure to mechanical abrasion (500 abrasion cycles and 1000 bending/release cycles), chemical corrosion (24 h of immersion in organic solutions), and UV aging (168 h). This strategy presents a fast and effective method for preparing multifunctional anti-fouling coatings, with potential applications on foldable screens, high-rise building glazing, and curved surfaces.

Exploring the potential of α-Ge(1 1 1) monolayer in photocatalytic water splitting for hydrogen production

In this study, the structural, electronic, and optical properties of 2D α-Ge(1 1 1) are investigated using Density Functional Theory (DFT) calculations, complemented by many-body perturbation theory calculations based on the GW/BSE approach. The thermodynamic stability of this material is assessed through ab initio molecular dynamics simulations (AIMD), and their dynamic stability is confirmed via phonon dispersion calculations. The analysis of the optical properties reveals significant absorption peaks in both visible and ultraviolet regions, with an absorption edge at 47 eV (1.87 eV without excitonic effects). The band edges are well-aligned with water redox potentials at neutral pH, making them suitable for water-splitting applications. For other pH levels, we find the process may be feasible through the participation of different excited states populated by light absorption. Remarkably, the α-Ge(1 1 1) monolayer demonstrates a predicted solar-to-hydrogen conversion efficiency of 34.80 %, outperforming many other two-dimensional materials. These findings position the α-Ge(1 1 1) monolayer as a promising candidate for developing efficient photocatalytic materials for hydrogen generation via overall water splitting.

Composite photocatalysts g-C<SUB>3</SUB>N<SUB>4</SUB>/TiO<SUB>2</SUB> for hydrogen production and dye decomposition

The photocatalytic activity of the g-C3N4 /TiO2 composite samples in the processes of dye (methylene blue) decomposition and hydrogen evolution from an aqueous ethanol solution under the action of visible radiation (400 nm) has been studied. A new original method for the synthesis of the g-C3N4 /TiO2 composite by depositing g-C3N4 /TiO2 to TiO2 nanoparticles during sol-gel synthesis is proposed. The synthesized photocatalysts were characterized by X-ray diffraction, low-temperature gas adsorption, X-ray photoelectron spectroscopy, high-resolution transmission microscopy, and diffuse reflectance spectroscopy in the UV and visible regions. The maximum activity in the hydrogen evolution reaction was 1.3 mmol h–1, which exceeds the rate of hydrogen evolution on the unmodified g-C3N4 and TiO2 samples.

Comparative study of natural dyes extracted from dark red and yellow Frangipani flowers (Plumeria rubra L.) as DSSC sensitizer

Dye-sensitized solar cells (DSSC) provide credible alternative for the inorganic solid-state photovoltaic devices. In this work, natural sensitizer extracted from Plumeria rubra L. flower (Frangipani) in ethanol has been used as the sensitizer dye. Dark red and yellow species of Frangipani flower petals extracted natural dyes have been studied for their comparative performance as sensitizer dye. FTIR revealed the presence of hydroxyl and carbonyl group in the sensitizer dye, which helped in binding with TiO2. UV-Visible analysis revealed absorption in visible region, which got broadened for dye loaded TiO2. Mass spectrometry confirmed major chemical constituents present in Plumeria rubra L. flower. For the HOMO and LUMO levels of dark red and yellow Frangipani flowers, the density functional theory (DFT) calculation was performed. Light-to-electricity conversion efficiency (ɳ%) of dark red Frangipani flowers was achieved 0.148 % with Voc 0.27 V, Jsc 0.88 mA/cm2 and FF 0.62, which was comparatively higher than yellow Frangipani flowers-based cell having ɳ% 0.128 % with Voc 0.54 V, Jsc 0.37 mA/cm2 and FF 0.64, respectively. For analyzing the charge transfer characteristics, electrochemical impedance spectroscopy (EIS) studies were carried out. The dark red species of Frangipani flower showed better result as sensitizer dye compared to the yellow species.

Investigation of methylene blue dye degradation using green synthesized mesoporous silver-titanium

In this study, we synthesized mesoporous silver-titanium (Ag/TiO2) through green synthesis approach using mangosteen pericarp extract, which subsequently can act as both adsorbent and photocatalyst materials. Additionally, we investigated and compared the degradation of methylene blue (MB) using mesoporous Ag/TiO2 under dark conditions, visible light irradiation, and both dark-light conditions to analyze the adsorption-photocatalysis activity. The achieved mesoporous structure in this study offers distinct advantages as an adsorbent. Moreover, the addition of silver (Ag) to titanium dioxide (TiO2) shows promise in enhancing photocatalytic activity in MB degradation, which enhances photocatalytic activity in the visible light region due to its localized surface plasmon resonance (LSPR), which excites more electrons, resulting in increased MB degradation. The highest degradation percentage of 97.08 % was obtained using a dark-light degradation mechanism, demonstrating that the synthesized mesoporous Ag/TiO2 has potential as an effective integrated adsorbent-photocatalyst material for MB dye degradation.

Critical current density of high-temperature superconducting ceramics BSCCO Bi-2223

In the paper the results of the study on the synthesis of high-temperature superconducting ceramics of nomi- nal composition Bi1.6Pb0.4Sr2Ca2Cu3Oy by various methods were presented based on amorphous phases using glass-ceramic technology and solid-phase method. For comparison, amorphous phases were obtained in two ways. In the first case, a heating furnace of a special design was developed to obtain an amorphous phase, which provides melting without using a crucible. The heating of the initial samples for melting is carried out due to the combined effect of the convection heat flux and the radiation of heating elements, which consists of the IR region of the spectrum at a melting temperature in the spectral range of 1300–1350 nm. In the se- cond case, melting is carried out under the influence of broadband optical radiation, including UV, visible and IR spectral regions. The production of glassy precursors is carried out by draining the melt onto a quenching device in the form of a propeller made of stainless steel. Studies of the formation rate of the superconducting high-temperature phase Bi-2223 were carried out in the same temperature conditions at 848–850 °C with in- termediate grinding every 24 hours and the study of the phase composition by X-ray diffraction method. Studies showed that the glass phase-based method ensures the completeness of the formation of the high- temperature phase Bi-2223 and the rate of its formation is significantly higher than by the solid-phase method (2.5–3 times). Studies of the critical density of the transport current have shown that the current value is 7.05×103 mA/cm2, (measured by the criterion of 1 µV/cm), which is significantly higher compared to other methods.

First principles calculations of double perovskite RbX2Y3O10 (X = Ca, Ba: Y[dbnd]Cd, Ta) materials for photocatalytic applications

Production of oxygen and hydrogen energy through suited photocatalysts by water splitting is the main issue in the modern age. In this regard, the double perovskite Dion-Jacobson materials RbX2Y3O10 (X = Ca, Ba: YCd, Ta) for photocatalytic activity are investigated by using the CASTEP package. The plane-wave (PW) pseudo-potential in the context of the generalized gradient approximation (GGA)-Perdew Burke Ernzerhof (PBE) and local density approximation (LDA) exchange-correlation functional technique is used to investigate the compounds. According to the results, compounds have a tetragonal (a = b≠c) structure with space group 123 (p4/mmm). Compounds Mullikan bond populations were estimated in order to comprehend the bonding characteristics that found a mixed ionic and covalent bonding. According to electronic characteristics, RbBa2Ta3O10, RbBa2Cd3O10, and RbCa2Cd3O10 have semiconductor behavior with indirect bandgap of 2.11 eV, 2.27 eV, and 1.51 eV, respectively, and respond under visible region light. DOS and PDOS are studied to inspect the distinct atom's contribution to electronic band structure. The compounds are mechanically brittle (1.55, 1.39), ductile (1.97), and stable in their natural form, according to elastic constant values. The optical characteristics simulation indicates that compounds have the potential to decompose or oxidize organic contaminants. According to the results, these compounds are suitable for the water-splitting photocatalytic process to produce oxygen and hydrogen.

Ab initio study of iron-doped zinc oxide for efficient dye degradation

First principle calculations were performed on iron doped zinc oxide (Fe-ZO) to reduce its bandgap to optimize its visible light absorption. The doping of iron in the ZO is done via supercells of Zn1-xFexO. The doped systems are analyzed using generalized gradient approximation plane wave pseudopotential on density functional theory, or local density approximation and LDA + U with PBE. The computational analysis reveals that the bandgap reduced with increasing dopant concentration. Furthermore, a robust absorption is observed toward the visible region of the spectrum. This enhances its ability as a photochemical material to increase degradation rates of industrial grade dyes.

Ab-initio investigation of structural, electronic, thermoelectric and optical properties of Full-Heusler X2MnB (X = Ti, Zr) for energy harvesting applications

In this manuscript comprehensive first-principles calculations have been presented for Full-Heusler X2MnB (X = Ti, Zr) compounds. This work includes detailed observations of the structural stability, origin of the transport phenomenon, optical properties, and electronic response. Structural parameters support the previous findings by confirming structural stability in the non-magnetic phase. Ti2MnB (Zr2MnB) valence band maxima and conduction band minima have bandgaps of 0.217 (0.301) eV and 0.181 (0.209) eV for PBE-GGA (mBJ) approximations which lie between L-L symmetry points. Due to the comparative measurements of the two states, the DOS results show that the Ti1/Zr1, Ti2/Zr2 Mn eg, and t2g states mainly contribute to the valence band region for Ti2MnB and Zr2MnB alloys, confirming their ionic nature. The computation of the overall electronic parameters’ reveals semiconducting nature. Thermoelectric properties have been calculated as a function of temperature in the 100–1200 K range. The positive values of Seebeck coefficients specify p-type character of X2MnB While at 300 K, Zr2MnB and Ti2MnB showed the highest Seebeck coefficients, measuring roughly values of 268 (µK/V) and 243 (µK/V), respectively. These values suggest that the material exhibits high thermoelectric performance. Though high optical absorption coefficient and low reflectivity in the visible and ultra violet regions, confirms use of these materials in solar cell applications. These findings suggest that material holds great potential for use in thermoelectrical applications which can support in upcoming experimental considerations.

Spray pyrolysis grown Cu and Ni co-doped ZnO thin films: a study of their structural, optical, wettability, and photocatalytic performance

This study explores the impact of Cu and Ni doping on the structural, wettability, optical, and photocatalytic properties of ZnO thin films. The co-doped thin films, with varying Ni concentrations, were deposited using a spray pyrolysis method onto pre-heated soda lime glass substrates. X-ray diffraction analysis confirmed the hexagonal wurtzite structure with preferred orientation primarily along the (002) plane, while crystallinity decreased with higher Ni concentrations. Scanning electron microscopy reveals a compact, adherent structure in all films, with Ni incorporation altering the surface morphology. Fourier transform infrared spectroscopy identified characteristic absorption bands for metal-oxygen bonds. Optical analysis indicated that all thin films exhibited over 88% average transmittance in the visible region, accompanied by a red shift in the optical bandgap. Photoluminescence spectra exhibited a broad emission band in the visible region, indicating intrinsic and extrinsic defects induced by doping. Co-doping transforms the wettability character of ZnO thin films from hydrophilic to hydrophobic. Finally, the photodegradation efficiency of the thin films against methylene blue under sunlight significantly increases from 72% to 92% with an increase in Ni concentration.

Towards Efficient White-light Emission in Sulfur Dots through Surface Charge Engineering.

Sulfur dots (SDs) have emerged as promising photoluminescence (PL) materials owing to their intrinsic merits such as abundant electronic effects, outstanding biocompatibility and available photocatalytic activity. Typically based on quantum confinement effects, SDs are reported usually confined emission in blue-to-green region. However, it is challenging to achieve their broad emission tunability in the visible region, restricted by inherent band gap of bulk sulfur (ca. 2.79 eV). Herein, we present white-light-emitting SDs achieved by surface charge engineering that hybridizes the surface of SDs with oleylamine. The resulting SDs exhibit broadband emissions (full width at half maximum of 187 nm) with PL quantum yields of up to 12.1% and Commission International de I'Eclairage color coordinates of (0.27, 0.32). Detailed experimental and calculation results reveal that the strong orbital coupling between oleylamine and sulfur on the hybrid surfaces of the SDs causes electron delocalization, leading to the generation of low-energy charge transfer (CT) states. These CT states are highly sensitive to sulfur-oleylamine hybrid structures, which complicate the transition dynamics and promote multi-energy emission, accounting for efficient white-light emission. The demonstration of white-light SDs based on surface charge engineering is an important step towards the development of sulfur-based PL materials.

Enhanced photocatalytic oxidation of gaseous acetaldehyde using Fe-grafted ZnO nanocomposites in a continuous flow reactor

The purification of indoor air is a crucial application of photocatalysis, emphasizing the urgent need for more efficient photocatalytic systems. While photocatalytic oxidation of volatile organic compounds (VOCs) has been extensively studied in the liquid phase, effective removal of VOCs in the gaseous state in indoor air remains a significant challenge. This study focuses on the continuous gas-phase oxidation of gaseous acetaldehyde using ZnO and different weight percentage of Fe-grafted ZnO catalysts under light irradiation. The surface analysis using XPS and HR-TEM confirmed the presence of Fe(III) species, and UV–Vis-DRS analysis demonstrated a shift in the absorption edge towards the visible region. Real-time gas FTIR monitoring of acetaldehyde oxidation revealed that the 0.7% Fe(III)-grafted ZnO composite catalyst achieved a higher removal efficiency (74%) compared to bare ZnO and other Fe(III)-grafted ZnO ratios. The enhanced photocatalytic efficiency of acetaldehyde by Fe(III)-grafted ZnO supports indicated direct interfacial charge transfer (IFCT) from ZnO to Fe(III) species. Additionally, the Fe(III) cluster effectively improved the separation of electrons and holes, preventing their recombination and accelerating O₂ activation to generate O₂•⁻ radicals, which lead to high photocatalytic performance. The 0.7% Fe(III)-grafted ZnO also maintained its performance over a prolonged period of 360 min, showing excellent structural stability and durability across multiple cycles. This study highlights the possible synergistic effect of the ZnO and Fe systems, offering a new perspective on the photocatalytic decomposition of gaseous acetaldehyde in indoor environments.

Tunable electronic and optical properties of a type-II GaP/SiH van der Waals heterostructure as photocatalyst: A first-principles study

In this study, a novel GaP/SiH heterostructure was successfully predicted and constructed. Subsequently, an in-depth and systematic investigation was conducted to explore its structural, electronic, transport and optical properties. The calculated structural performance results revealed that the GaP/SiH heterostructure was a typical type-II van der Waals heterostructure, exhibiting excellent energy stability, mechanical stability and thermodynamic stability. In particular, the formation of the GaP/SiH heterostructure significantly reduced the bandgap of the materials to 2.24eV, and the type-II energy band arrangement effectively suppressed the recombination of photogenerated carriers. Furthermore, the biaxial and vertical strains could finely modulate the electronic structure of the GaP/SiH heterojunction. The electron mobility of the GaP/SiH heterostructure was measured to be 1573.91 cm2 V⁻1 s⁻1, indicating its superior charge carrier transport capabilities. Meanwhile, the GaP/SiH heterostructure also exhibited excellent optical absorption performance in the visible and UV region up to 2.34 × 106 cm−1. Thus, the GaP/SiH heterostructure will be a strong candidate for photocatalytic applications due to its excellent light absorption properties, electrical properties, and stability.

Visible LED-light driven photocatalytic activity by a novel magnetically separable CoFe2O4/Mn3O4 nanocomposite

A novel magnetic separable CoFe2O4/Mn3O4 semiconductor catalyst was synthesized by sol-gel-cum-hydrothermal method, successfully. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman, and Fourier transformed infra-red spectrometers were used to characterize the prepared samples. Mn3O4 and CoFe2O4 exhibit in tetragonal and cubic phases, respectively. The obtained direct optical band gap of the samples belongs to the visible region. These catalysts were employed in photo-degradation of methylene blue (MB) dye under an LED visible light. Coupling of CoFe2O4 with Mn3O4, which formed type-II heterojunction, enhances the photocatalytic efficiency, provides magnetic separable features, and prevents the charge carriers’ recombination. Synthesized CoFe2O4/Mn3O4 nanocomposites show excellent photocatalytic activity with a high value of rate constant ∼ 0.03889 minute−1. The scavenging test reveals that the holes and superoxide radicals were dominant reactive species in the degradation of dye. Magnetic separable feature of nanocomposite helps to recover the catalysts from degraded MB dye solution for the next photo-degradation cycles.

Effect mechanism of Cd on band structure and photocatalytic hydrogen production performance of ZnS

ZnS is widely used in the photocatalytic decomposition of water to produce hydrogen due to its fast electron-hole pair generation and high negative potential. However, its absorption in the visible region is poor due to its wide band gap, and it has serious photogenerated carrier recombination problems. Herein, a shallow impurity energy level was introduced by doping the ZnS lattice with Cd. Due to its presence, electrons trying to return to the valence band are trapped and excited twice, suppressing the recombination of photogenerated carriers and greatly improving electron utilization. The Cd1.5-ZnS possesses a hydrogen production rate as high as 85722.20 μmol/g, which is 17 times higher than pure ZnS. Meanwhile, Cd1.5-ZnS has a narrower forbidden band and superior visible light absorption, and the serious photocorrosion problem of ZnS has been suppressed. This study provides a viable approach for the synthesis of photocatalysts with adjustable band gaps and enhanced hydrogen precipitation efficiency.

Sol-gel synthesis of LaFeO3 perovskite oxide for distinct ridges detection of level II and III latent fingerprints

Latent fingerprints are considered a primary source of best reference for personal identification in criminal investigations. However, poor resolution, less background hindrance, and sensitivity over fingerprint ridges are often problems in fingerprint development. To address these issues, special care is required by developing new fluorescence materials. As a result, this effort was made to synthesize lanthanum ferrite (LaFeO3) fluorescent nano perovskite oxide by the sol–gel method using glycine as fuel, to detect three (I, II, and III) levels of fingerprints. In addition, the absorption spectrum was recorded in a dispersed medium, and dual peaks at 329 and 406 nm in visible regions were obtained, followed by the photoluminescence spectra that showed a broad peak at 527 nm with chromaticity coordinates. Powder X-ray diffraction confirms the synthesized LaFeO3 orthorhombic phase with a crystallite size of 54 nm, and the morphology of LaFeO3 was found to be highly monodisperse. X-ray photoelectron spectroscopy confirmed that La has + 3 with Fe + 3 oxidation states, and Infrared spectroscopic techniques revealed all functional groups were present uniformly. The powder dusting method was applied on various porous and non-porous surfaces, revealing distinct ridges of fingerprints without background hindrance and with precise sensitivity; this proves LaFeO3 is suitable for forensic science.