Ba2B5O8(OH)2(NO3)·3H2O: the design of an alkaline earth metal borate-nitrate optimized from a hydroxylic borate

The first alkaline earth metal borate-nitrate, namely, Ba2B5O8(OH)2(NO3)·3H2O (BBNOH), has been synthesized by the hydrothermal method. BBNOH crystallizes in the space group of P21/c and exhibits two-dimensional (2D) 2∞[B5O8(OH)2]3-borate anion...

Enhancement of Gamma-ray Shielding Properties in Cobalt-Doped Heavy Metal Borate Glasses: The Role of Lanthanum Oxide Reinforcement

The direct influence of La3+ ions on the gamma-ray shielding properties of cobalt-doped heavy metal borate glasses with the chemical formula 0.3CoO-(80-x)B2O3-19.7PbO-xLa2O3: x = 0, 0.5, 1, 1.5, and 2 mol% was examined herein. Several significant radiation shielding parameters were evaluated. The glass density was increased from 3.11 to 3.36 g/cm3 with increasing La3+ ion content from 0 to 2 mol%. The S5 glass sample, which contained the highest concentration of La3+ ions (2 mol%), had the maximum linear (μ) and mass (μm) attenuation coefficients for all photon energies entering, while the S1 glass sample free of La3+ ions possessed the minimum values of μ and μm. Both the half value layer (T1/2) and tenth value layer (TVL) of all investigated glasses showed a similar trend of (T1/2, TVL)S1 > (T1/2, TVL)S2 > (T1/2, TVL)S3 > (T1/2, TVL)S4 > (T1/2, TVL)S5. Our results revealed that the S5 sample had the highest effective atomic number (Zeff) values over the whole range of gamma-ray energy. S5 had the lowest exposure (EBF) and energy absorption (EABF) build-up factor values across the whole photon energy and penetration depth range. Our findings give a strong indication of the S5 sample’s superior gamma-ray shielding characteristics due to the highest contribution of lanthanum oxide.

Multiple Optical Features In Binary-Transition-Metal Borate Glasses

Glasses doped with transition metal (TM) ions exhibit rich optical transitions spanning the entire ultraviolet, visible, and infrared spectral regimes. Here we utilize the melt-quenching techniques to synthesis binary-TM-doped borate glasses of composition xCuO-(75-x)B2O3-24.7Li2O-0.3Cr2O3, with x = 0, 0.2, 1.0 and 2.0 mol %. We identify several optical transitions from Cr3+, Cr6+, and Cu2+ ions, the latter manifests at longer wavelengths and gains higher intensity with Cu additives. Despite Cr concentration being fixed, the Cr6+ peaks are quenched and Cr3+ signals are barely attenuated. This behavior rules out possible phase separation and suggests non-trivial interplay between the two TM ions and ligand, as supported by probing their oxidation states from electron spin resonance. The crystal field and Racah parameters followed an opposite behavior, while the optical band gap is reduced upon doping. These changes are correlated with structural modifications introduced by Cu additives, where we anticipate homogenous and preferential proximity of Cu-Cr ions within the network.

Characterization and Antibacterial Properties of Metal Borates Vectorized As Ceramic Glaze Additives

Metal borate nanoparticles Silver (Ag), copper (Cu) and Zinc (Zn) were produced for a novel boron containing antibacterial ceramic applications. Different concentration, temperature, time parameters were varied for obtaining hierarchical metal borate embedded formulations. Synthesized nanostructures showed interesting crystalline and optical properties since temperature and concentration adjustments provided correlated shape and surface properties. Chemical analysis and crystallinity of both copper and silver formulations were defined using XRD and confirmed that temperature plays a deep role on the production of nanostructures. XPS analysis together with TEM investigations comprehensively provided all atomic compositions with their corresponding energy values in survey and high resolution region. Morphology and atomic purity was analyzed using EDX and SEM measurements revealed the morphological orientation of the nanostructures without other impurities. FT-IR and UV-Vis spectroscopy provided optical information about the obtained metal borate nanoparticles. Finally metal borate nanoparticles were utilized for 1x1 cm ceramic glazing samples for antibacterial applications. Silver borate nanoparticles were found to be more active in low concentrations than copper and zinc borate structures after the antibacterial test results were unveiled against to gram positive and gram negative microorganisms.