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In this work, uniform hierarchical mesoporous 3D-urchin-like Bi2S3@2D-nanosheet g-C3N4was synthesized viaa superficial hydrothermal method. The prepared pristine Bi2S3, g-C3N4, and 3D-Bi2S3@2D-g-C3N4composite samples were extensively studied for their electrochemical performance and exhibited superior battery-type behaviors. The results highlight that the optimized 3D-Bi2S3@2D-g-C3N4composite sample exhibits a high areal capacity of 41.53 μA h/cm2at 1 mA/cm2and a good rate capability of 62.77% along with a remarkable capacity retention of 94.86% after 5000 cycles. The improved performance can be attributed to the good beneficial features of the synergistic effect, mesoporous structure, and lower dissolution. It offers a higher specific surface area, enriches electroactive sites, increases electronic/ionic conductivities, and reduces the interfacial resistance. Furthermore, the solid-state symmetric supercapacitors (SSCs) were assembled by two similar electrodes of 3D-Bi2S3@2D-g-C3N4sandwiched between the KOH and PVA gel electrolyte. The fabricated SSC device provides a high areal capacity of 25.40 μA h/cm2at 1 mA/cm2. Furthermore, the SSC delivers a maximum power density of 1495 μW/cm2and an energy density of 3.17 μW h/cm2with a good cyclic retention of 83.84% after 7500 cycles. This work also demonstrates the practical applicability of realizing red-light-emitting diodes by interconnecting two SSCs in series.

The creation of ternary composite materials with innovative structures is crucial for enhancing the energy density and stability of supercapacitor devices. In this study, Ni(OH)2-based ternary composites were successfully synthesized using a straightforward hydrothermal method. Comprehensive analyses of structure, morphology, surface area, and binding energy were conducted using powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron microscopy. The electrochemical performance of the Ni(OH)2/MWCNT/CNF electrode displayed a higher specific capacitance of 882 F g−1and lower resistance compared to pure Ni(OH)2electrodes. An asymmetric supercapacitor device, assembled with the chosen Ni(OH)2/MWCNT/CNF and activated carbon (AC), exhibited energy and power densities of 47.5 Wh kg−1and 750 W kg−1, along with 83.42 % capacitance retention after 5000 charge-discharge cycles. These outstanding results confirm the potential of this material as an exceptional electrode for future supercapacitor applications.

We investigated the structure and magnetic properties of Ce-doped NiO and Co3O4samples. The multiemission centers created in the nanostructures observed from PL spectra were obviously due to the formation of interstitials (Niiand Coi) and oxygen vacancies (VO) by the incorporation of Ce3+ions into the lattice site which affects the band gap structure of the material. Room-temperature magnetic study was demonstrated for Ce-doped NiO and Co3O4nanostructures using a vibrating sample magnetometer. The origin of magnetism in these samples was related to the finite size and importantly oxygen vacancies created by the Ce ion dopant, which was confirmed from the decrease of magnetization value at room temperature compared to undoped NiO and Co3O4samples.

According to a resourceful survey, bimetallic selenides with their hierarchical nanostructures have gained widespread attention despite their enhanced electrical conductivity. Consequently, the incorporated morphology, structure, and constituent modulation of the foremost electrode endows it with a privileged trial for the transportation and diffusion of ions. The structural and morphological study agrees with the configuration of mono- and bimetallic selenides analytically. Herein, cobalt (Co) ions in their composite heterostructures find a fundamental role in the configuration of the nanostructure having fine conducting nature. Therefore, a nanosphere is merged arbitrarily to form a conductive network, which might ease charge transfer. Furthermore, the heterostructured NiSe2@CoSe2electrode displayed an improved specific capacitance of 531 F g–1at a current density of 1 A g–1, and an outstanding long-term durability of 99.88% was achieved over 5000 charge–discharge cycles. The nanostructure morphology and structure of the fabricated electrode predominantly stimulate its application in energy-related attributes because of large active sites, improved surface-to-volume ratio, and limited transport length of the ions. In addition, an assembled full cell NiSe2@CoSe2//AC with a paramount operating voltage of 1.5 V using 1 M KOH achieved an increased energy density of 41 Wh kg–1at a power density of 738 W kg–1with a retention of 99.86% over 5000 cycles. The highly assembled asymmetric device lights up a blue light-emitting diode (LED), demonstrating a voltage of 1.63 V. The existing protocol entails an excellent reference for various metal selenides for efficient storage appliances.

The various copper sulphate concentrations prepared CdS thin films were coated on glass substrates by chemical bath deposition. The structural, optical, functional group and morphological properties were studied using X-ray diffraction (XRD), UV-Vis-NIR spectrophotometer and scanning electron microscopy, respectively. The deposited films are found to be polycrystalline in nature with hexagonal structure along a (100) preferential orientation plane. The microstructural properties of CdS thin films such as crystallite size, micro strain, texture coefficient and lattice constant were calculated from structural studies and results are compared with earlier reports. The optical properties of CdS thin films band gap were lying between 2.38 and 2.49 eV. The stoichiometric composition with uniform surface morphological properties of the film was obtained in optimized molar concentration. The morphological images revealed that size of the grains was found to be 50 to 75 nm and some place group of grains agglomerate to form larger grains.

Optical constants of ZnSe thin films for various deposition potentials were determined in the spectral range 400 nm to 1200 nm using the optical absorption and transmittance measurements. The Tauc's plot were drawn to determine the energy band gap values of the deposited films and are estimated to be in the range between 2.52 eV and 2.61 eV respectively. Their optical constants like refractive index (n), dielectric constants (e), optical conductivity (s), average excitation energy (E0), oscillator strength (Ed), effective mass (m*), plasma frequency (op), static dielectric constant (e[?]) and carrier concentration (N) were estimated and reported. The room temperature photo luminescence studies were also performed. The near band edge luminescence emission has been observed and reported.

SnSSe solid solution thin films were electrosynthesized from an aqueous solution by potentiostatic method. Films were deposited at different potentials in the range of -700 mV to -1000 mV vs SCE. XRD patterns revealed that the deposited films exhibited polycrystalline orthorhombic structure with preferred orientation along (111) crystallographic plane. The optical band gap value was calculated from transmittance and absorption data and the films were found to have direct band gap found to be 1.08 eV-1.25 eV. The refractive index, extinction coefficient, real and imaginary part of dielectric constants and optical conductivity of the SnSSe thin films has been calculated. The value for the refractive index lies between 2.5 and 3.1 and value of extinction coefficient lies between 0.035 and 0.052. Surface morphological studies revealed pellet shaped grains occupying the entire surface of the film distributed homogeneity.

Lifetimes of two-color nonvolatile holograms recorded in undoped or in slightly doped near-stoichiometric lithium niobate and tantalate crystals were measured and compared by extrapolation of the high-temperature data. A proton-compensation mechanism dominated the dark decay and yielded similar activation energies, of 1.05 and 1.10 eV, for near-stoichiometric lithium niobate and tantalate crystals, respectively. The lifetime of holograms in lithium tantalate was 1 order of magnitude longer than that in lithium niobate with the same proton concentration, which was consistent with our theoretical estimation. The projected lifetime of two-color holograms in lithium tantalate without observable OH^- absorption is longer than 50 years.

Photoelectrochemical water splitting symbolizes an eco-friendly sustainable way for renewable hydrogen and oxygen production. Increasing the photoelectrode stability and efficiency is one of the important tasks in PEC performances. In this present work, we have successfully synthesized pure ZnO and ZnSe1 – xOxnanorods by a chemical vapor deposition method. XRD measurements confirmed the formation of the wurtzite structure of ZnO and ZnSe1 – xOxnanorods. All the prepared samples confirmed the formation of the nanorod structure by employing SEM studies. Notably, in particular, the photoelectrochemical (PEC) activity was studied by linear sweep voltammetry (I–V) and photoconversion efficiency (η) analysis. The experimental results showed that the ZnO/0.2Se nanorods exhibit better PEC performance due to their strong visible light absorption. The selenium (Se) composite plays a vital role in boosting their PEC performance and photoelectrode efficiency. Furthermore, the optimized photoanode of ZnO/0.2Se exhibits high efficiency, which was 2.73 times greater than that of the pure ZnO. Therefore, the ZnSe1 – xOxnanorod is a promising alternative material for PEC applications.

Two-color holographic recording was performed in near-stoichiometric LiNbO3 crystals doped with 50-ppm Mn, where the crystals were thermally annealed in different oxidation/reduction atmospheres. Two-color recording properties including sensitivity, dynamic range, activity energy, and dark decay time were measured and compared, and the results were explained reasonably by measuring some characteristic material parameters.

The various copper sulphate concentrations prepared CdS thin films were coated on glass substrates by chemical bath deposition. The structural, optical, functional group and morphological properties were studied using X-ray diffraction (XRD), UV-Vis-NIR spectrophotometer and scanning electron microscopy, respectively. The deposited films are found to be polycrystalline in nature with hexagonal structure along a (100) preferential orientation plane. The microstructural properties of CdS thin films such as crystallite size, micro strain, texture coefficient and lattice constant were calculated from structural studies and results are compared with earlier reports. The optical properties of CdS thin films band gap were lying between 2.38 and 2.49 eV. The stoichiometric composition with uniform surface morphological properties of the film was obtained in optimized molar concentration. The morphological images revealed that size of the grains was found to be 50 to 75 nm and some place group of grains agglomerate to form larger grains.

Optical constants of ZnSe thin films for various deposition potentials were determined in the spectral range 400 nm to 1200 nm using the optical absorption and transmittance measurements. The Tauc's plot were drawn to determine the energy band gap values of the deposited films and are estimated to be in the range between 2.52 eV and 2.61 eV respectively. Their optical constants like refractive index (n), dielectric constants (ε), optical conductivity (σ), average excitation energy (E0), oscillator strength (Ed), effective mass (m*), plasma frequency (ωp), static dielectric constant (ε∞) and carrier concentration (N) were estimated and reported. The room temperature photo luminescence studies were also performed. The near band edge luminescence emission has been observed and reported.

SnSSe solid solution thin films were electrosynthesized from an aqueous solution by potentiostatic method. Films were deposited at different potentials in the range of -700 mV to -1000 mV vs SCE. XRD patterns revealed that the deposited films exhibited polycrystalline orthorhombic structure with preferred orientation along (111) crystallographic plane. The optical band gap value was calculated from transmittance and absorption data and the films were found to have direct band gap found to be 1.08 eV-1.25 eV. The refractive index, extinction coefficient, real and imaginary part of dielectric constants and optical conductivity of the SnSSe thin films has been calculated. The value for the refractive index lies between 2.5 and 3.1 and value of extinction coefficient lies between 0.035 and 0.052. Surface morphological studies revealed pellet shaped grains occupying the entire surface of the film distributed homogeneity.