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

The direct influence of La 3+ ions on the gamma-ray shielding properties of cobalt-doped heavy metal borate glasses with the chemical formula 0.3CoO-(80-x)B 2 O 3 -19.7PbO-xLa 2 O 3 : 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/cm 3 with increasing La 3+ ion content from 0 to 2 mol%. The S5 glass sample, which contained the highest concentration of La 3+ ions (2 mol%), had the maximum linear (μ) and mass (μ m ) attenuation coefficients for all photon energies entering, while the S1 glass sample free of La 3+ ions possessed the minimum values of μ and μ m . Both the half value layer (T 1/2 ) and tenth value layer (TVL) of all investigated glasses showed a similar trend of (T 1/2 , TVL) S1 > (T 1/2 , TVL) S2 > (T 1/2 , TVL) S3 > (T 1/2 , TVL) S4 > (T 1/2 , TVL) S5 . Our results revealed that the S5 sample had the highest effective atomic number (Z eff ) 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.