Physical, FTIR, ultrasonic, and dielectric characteristics of calcium lead-borate glasses mixed by Nd_2O_3/Er_2O_3 rare earths: experimental study

摘要

Physical, FTIR, ultrasonic, and dielectric characteristics of calcium lead-borate glasses: 50B_2O_3-30CaO-20PbO-xEr_2O_3-yNd_2O_3:' (x,y) = (0,0; BCP), (0,1;1Nd), (1,0;1Er), and (1,1;1Nd-1Er) mol% have been examined. Nd~(3+) ions increased density up to 3857 kg/m3, meanwhile, molar volume barely changed. Er_2O_3 mol% decreased density down to 3641 kg/m~3, while molar volume increased up to 2.75 × 10~(-5) m~3. As well, Nd_2O_3 mol% + Er_2O_3 mol% decreased density down to 3556 kg/m~3, while molar volume increased up to 2.91 × 10~(-5) m~3. Er~(3+) and Nd~(3+) ions have different effects on the formation rate of BO~-_4 and BO_2O~-structural units. PbO in the glassy systems can be incorporated into the glass as network-forming Pb-O groups (PbO_4 and/or PbO_3). Introducing of Nd~(3+) ions induces changes in the local field on the lead ions giving rise to the formation of [PbO_4] units. The addition of Er~(3+) and/or Nd~(3+) to glass systems revealed that there was observed withdrawal of the area of PbO_(4-) absorption IR band and increasing both of longitudinal and shear velocity. The elastic moduli of the investigated glasses have a fingerprint of density behavior versus rare-earth content. Dielectric constant and ac conductivity were obviously enhanced by the insertion of Nd~(3+)/Er~(3+) ions separately or together into borate glass matrix referring to the creation of non-bridging oxygen.