Radiolysis of quench-cooled pure and barium doped KNO3 in presence of oxides: Effect of particle size

Radiation decomposition studies of quenched pure KNO₃ and KNO₃ doped with Ba²⁺ ions in the presence of PbO or Al₂O₃ as a heterophase impurity showed that the yield of nitrite varied with the particle size of the nitrate. The G/NO₂^–/ values were also found to vary with the mol percent of PbO or Al₂O₃ in the mixture. Higher yields of nitrite were obtained in the presence of PbO, while in mixtures containing Al₂O₃, the yields of nitrite were lower in comparison with the G-values observed in the absence of oxide. These results are explained on the basis that a larger surface area results in an increased energy transfer at the interface between two neighbouring particles. The results can also be accounted for in terms of electron donor-acceptor properties of the added oxides.