Synthesis, Spectroscopic, and Antibacterial Characterizations of Cadmium-Based Nanoparticles.

In the current study, the co-precipitation technique was employed for the synthesis of Cadmium oxide (CdO) and Copper‒doped Cadmium oxide (Cu‒CdO) nanoparticles. The synthesized samples were subjected to powder X-Ray diffraction (P-XRD), Field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray (EDX), Fourier transforms Infrared (FT-IR), UV-Vis spectroscopy, photoluminescence (PL), laser-induced fluorescence spectroscopy and antibacterial investigations. According to the P-XRD analysis, both the samples were simple cubic in structure and have average grain sizes of 54 and 28 nm, respectively. FE-SEM was deployed to explore the surface textures of the samples. EDX technique was used to look at the elemental compositions of the samples. The technique of FT-IR was employed to identify the vibrational modes. UV-Vis spectra in diffuse reflectance mode were obtained and the optical bandgaps of the CdO and Cu‒CdO samples were obtained as 4.52 eV and 2.83 eV, respectively. The photoluminescence studies were conducted at an excitation wavelength of 300 nm and emission peaks were red-shifted in both samples. Fluorescence spectroscopy was applied to explore the lifetimes of synthesized nanoparticles. The technique of Agar-well diffusion was applied to assess the antibacterial performance of the generated nanoparticles against Micrococcus Luteus (gram-positive) and Escherichia coli (gram-negative) bacterium at variable concentrations. Both samples in the current study are significantly effective against both bacterial strains.

Synthesis, Structural, Spectroscopic, Fluorescence, and Dielectric Studies of Bis-(4-Aminopyridine)-Zinc(II) Acetate: A Metal-Organic Crystal.

The advancement of crystalline growth and characterization tools allows us to investigate novel nonlinear optical substances suitable for photonic applications. Bis-(4-aminopyridine)-zinc(II) acetate (B4AZA), a metal-organic crystal was produced in this study using the slow evaporation procedure at room temperature. Analytical studies such as X-ray crystallography, Fourier transform infrared (FT-IR), UV-visible (UV-Vis), fluorescence, second harmonic generation (SHG), and dielectric tests were used to characterize the as-grown B4AZA crystals. According to the solubility data, the sample has a positive temperature coefficient of solubility. The crystallographic findings show that the B4AZA crystallized in a monoclinic structure with the P21/n space group. Molecular vibrations and functional groups in the substance were determined using the FT-IR technique. The UV-Vis absorbance and transmittance spectra have shown the wide transparency and minimum absorbance of the B4AZA in the near UV and entire visible regions of the electromagnetic spectrum. The bandgap of the B4AZA has been calculated using the Tauc relation and found to be 4.32 eV. The fluorescence spectra have shown a prominent emission peak at 584 nm with an excitation wavelength of 280 nm. The larger Stokes shift found in the fluorescence spectra is advantageous for practical applications. The SHG study revealed that the powdered B4AZA samples generated a second harmonic output. The dielectric test revealed frequency-dependent changes in the dielectric constant and loss factor. Both the dielectric constant and the loss factor decrease exponentially as frequency increases, reaching low values at higher frequencies. The experimental results illustrate the suitability of the B4AZA crystals for photonic applications.

Synthesis, Spectroscopic, Optical, and Thermal Characterizations of Zinc (Tris)-Thiourea Sulfate: A Metal-Organic Crystal.

In the current research, Zinc (tris)-thiourea sulfate (ZTTS), a metal-organic crystal, has been synthesized using the slow solvent evaporation technique. Powder-X-ray diffraction (PXRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, UV-Vis spectroscopy, photoluminescence (PL) spectroscopy, and thermal, and second harmonic generation measurements have all been applied to describe the as-synthesized ZTTS crystals. The synthesized samples crystallized in an orthorhombic structure, based on XRD analysis. The functional groups of ZTTS samples were validated by FT-IR analysis. The extensive transparency of ZTTS over the UV-visible spectral region has been confirmed by UV-Vis analysis and the band gap has been estimated as 4.43 eV. The photoluminescence spectra exhibit a prominent emission peak around the wavelength of 484 nm and significant emission peaks at 444 and 513 nm with an excitation wavelength of 250 nm. The SHG test illustrates the creation of second harmonic signals from the ZTTS samples. The thermal response of the as-synthesized ZTTS was shown by the TG/DTA measurements. The results suggest that as-synthesized ZTTS crystals could be used as a possible nonlinear optical substance.