Prospecting of structural, optical and magnetic traits of high-performance SrO-doped cobalt borate glass

Abstract

SrO-doped glass is high-performance materials for scientific research, recent technology and industry. This work introduces SrO-doped cobalt borate glass fabricated by melting and quenching method, and scrutinized by various techniques like X-ray diffraction, energy dispersive X-ray, density, infrared, optical and spin resonance of electron spectroscopies. Further, the non-linear optical properties were determined considering SrO addition. The disordered nature and the chemical formula of glasses were confirmed. The increased density from 2.77 gc m − 3 to 3.21 gc m − 3 and the decreased molar volume from 31.00 c m 3 / mol reaching 28.87 c m 3 / mol confirm the network crosslinking with a degree of compactness. Infrared spectra confirmed the structural transformation (i.e., B O 4 to B O 3 conversion from 42.41% to 51.32%), with significant decrease in non-bridging oxygen bonds from 9.82% to 1.86%. On optical properties, the optronic transitions of cobalt ions at specific wavelengths give the glasses their optical traits, indicating the domination of C o 2 + over C o 3 + ions. The transitions at ∼ 575 nm (ν 3 ) and ∼ 1497 nm (ν 2 ​) are assigned to C o 2 + in tetrahedral symmetry and used to determine the ligand field parameters. 10Dq increased from 3174 c m − 1 to 3218 c m − 1 , while Racah parameter B decreased from 970 c m − 1 to 943 c m − 1 , reflecting the high electron’s delocalization on C o 2 + cations, and enhancing the covalent bonding character of bonds between C o 2 + ions and ligands. The optical band gaps decreased from 3.81 to 3.23 eV, owing to the electronic structure of strontium, while Urbach energy increased from 0.30 to 0.21 eV due to the enhanced amorphousness. Further, the SrO additions boosted the enhancement in the non-linear optical properties of glass. The signals of electron spin resonance at g ≈ 4.058 and 2.19 revealed the presence of C o 2 + ions in octahedral (Oh) and tetrahedral (Td) symmetries, respectively. Some signals’ intensity variations revealed the domination of octahedral coordination. Here, the current investigations reveal a high-performance SrO-borate glass, offering correlated structure with magnetic and optical traits for some optoelectronic applications.