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L-proline tartrate (LPT), 1 and 2 mol% of lanthanum chloride- (LaCl3-) doped LPT single crystals have been synthesized and grown using a slow evaporation solution method at room temperature. The crystals have undergone different characterization studies to test their suitability for device fabrication. The single crystal X-ray diffraction studies have revealed that both 1 and 2 mol% of LaCl3-doped LPT single crystals have been crystalized monoclinic crystal structure and space group P21. The UV-Vis-NIR spectrum analysis has shown that pure, 1, and 2 mol% of LaCl3-doped LPT single crystals have good optical transparency in the entire visible and near IR region. The optical band gap energy for pure, 1 and 2 mol% of LaCl3-doped LPT single crystals to be 4.9, 5, and 5.1 eV, respectively. The energy dispersive X-ray analysis confirmed that LaCl3 has been incorporated into LPT crystal. The second harmonic generation (SHG) efficiency for 1 and 2 mol% of LaCl3-doped LPT single crystals has been tested and found to be 1.27 and 1.6 times greater than that of the reference KDP crystal, respectively.

Triglycine sulphate (TGS) and 1 and 2 mol% of magnesium chloride-doped TGS single crystals have been grown by using the slow evaporation solution method at room temperature. Pure and magnesium chloride-doped triglycine sulphate single crystals in a dimension of 12 × 12 × 5 cm3 have been grown at room temperature. The grown samples have been investigated by various characterization techniques such as single crystal X-ray diffraction, UV-VIS/NIR spectroscopy, dielectric studies, and energy dispersive X-ray analysis (EDAX). The single crystal X-ray diffraction studies revealed that both 1 and 2 mol% of MgCl2-doped TGS single crystals have been crystallized in monoclinic crystal structure with space group P21/m. The UV-VI/NIR spectra analysis confirmed that both pure and 1 and 2 mol% of MgCl2-doped TGS single crystals have wide optical transparency in the wavelength range of 236–1100 nm. The bandgap energy of both samples has been found to be 5.25 eV. The dielectric properties of the grown samples were recorded by measuring the dielectric constant as a function of temperature from 45 to 55°C with various frequencies (100 Hz – 1 MHz). The dielectric studies revealed that the dielectric constants of 1 and 2 mol% of MgCl2-doped TGS single crystals were increased with decreasing frequency and that the transition temperature was found to be 51°C. The EDAX spectrum confirmed the incorporation of MgCl2 into TGS single crystals.

Fe:TiO2 nano particles were deposited through sol-gel techniques, and the influence of pH values on structural, morphological, optical, and photoluminescence spectral behaviors was studied. Iron doped titanium dioxide nanopowders were analyzed using XRD, SEM, UV–ViS, and PL. Nano crystallized samples of titanium dioxide (72 nm, 77 nm, 78 nm, and 83 nm) were gained from X-Ray diffraction data and showed that there was the creation of unalloyed anatase and ructile segment with tetragonal configuration. The average crystal size was 77.5 nm. pH values provide the alteration of segments from anatase to ructile. The crystal size of prepared iron doped titanium dioxide nanoparticles was greater than before as pH value rises from 2 to 6 while FWHM and scrap sizes declined. Homogeneously disseminated cylindrical forms of iron doped titanium dioxide nanoparticles were perceived from scanning electron microscope graphics and rises in size with growing pH values from 2 to 6 in an acidic medium. Extremely translucent nanopowders are witnessed in the observable region by visible and redshifts near advanced wavelengths with rising pH values because of an increase in the size of particles from XRD data and SEM micrographs. The band gap of energy produced by nano concentrates was reduced with growing pH values that resemble the redshift of optical absorption superiority. The structural behaviors of deposited nanoparticles were also analyzed by Raman spectra and disclosed the existence of tetragonal anatase and ructile segments. EDS results confirmed that the dopant of pH values of the solutions might affect the size distributions of the Fe: TiO2 nanoparticles. The general decrement intensity was witnessed from photoluminescence outcomes.

Cobalt sulfide thin films were synthesized from acidic chemical baths by varying the deposition time. The powder X-ray diffraction studies indicated that there are hexagonal CoS, face-centered cubic Co3S4, and cubic Co9S8 phases of cobalt sulfide. The crystallite size of the hexagonal CoS phase decreased from 52.8 nm to 22.5 nm and that of the cubic Co9S8 phase increased from 11 nm to 60 nm as the deposition time increased from 2 hrs to 3.5 hrs. The scanning electron microscopic images revealed crack and pinhole free thin films with uniform and smooth background and few large polygonal grains on the surface. The band gap of the cobalt sulfide thin films decreased from 1.75 eV to 1.3 eV as the deposition time increased from 2 hrs to 3.5 hrs. The photoluminescence (PL) spectra of the films confirmed the emission of ultraviolet, violet, and blue lights. The intense PL emission of violet light at 384 nm had red shifted with increasing deposition time that could be resulted from the increase in the average crystallite size. The FTIR spectra of the films indicated the presence of OH, C-O-H, C-O, double sulfide, and Co-S groups. As the deposition time increased, the electrical resistivity of the cobalt sulfide thin films decreased due to the increase in both the crystallite size and the films’ thickness.

ZnS/glass and CdS/glass single layers and ZnS/CdS and CdS/ZnS heterojunction thin films were deposited by the chemical bath deposition method using zinc acetate and cadmium acetate as the metal ion sources and thioacetamide as a nonmetallic ion source in acidic medium. Na2EDTA was used as a complexing agent to control the free cation concentration. The single layer and heterojunction thin films were characterized with X-ray diffraction (XRD), a scanning electron microscope (SEM), energy dispersive X-ray (EDX), and a UV-VIS spectrometer. The XRD patterns of the CdS/glass thin film deposited on the soda lime glass substrate crystalized in the cubic structure with a single peak along the (111) plane. The ZnS/CdS heterojunction and ZnS/glass single layer thin films were crystalized in the hexagonal ZnS structure. The CdS/ZnS heterojunction thin film is nearly amorphous. The optical analysis results confirmed single band gap values of 2.75 eV and 2.5 eV for ZnS/CdS and CdS/ZnS heterojunction thin films, respectively. The CdS/glass and CdS/ZnS thin films have more imaginary dielectric components than the real part. The optical conductivity of the single layer and heterojunction films is in the order of 1015 1/s. The optical study also confirmed refractive index values between 2 and 2.7 for ZnS/glass, ZnS/CdS, and CdS/ZnS thin films for incident photon energies between 1.2 eV and 3.8 eV. The surface morphology studies revealed compacted spherical grains covering the substrate surfaces with few cracks on ZnS/glass, ZnS/CdS, and CdS/glass and voids on CdS/ZnS thin films. The EDX result confirmed nearly 1 : 1 metallic to nonmetallic ion ratio in the single-layered thin films and the dominance of Zn ion over Cd ion in both ZnS/CdS and CdS/ZnS heterojunction thin films.