Abstract:
Insertion of MoO3 oxide in the mixed borophosphate glass network has been analysed for the first time by advanced magnetic resonance spectroscopies. In a first time, the xMoO3-(100-x)(50PbO-10B2O3-40P2O5) composition line has been investigated by 1D (11B, 31P, 95Mo) and 2D-correlation NMR (11B DQ-SQ, 11B(31P) D-HMQC) at high magnetic field (18.8 T). The set of data allowed analyzing both local and medium range orders and identifying the modifications in the BOB and /or BOP mixing induced by the MoO3 insertion. In a second step, continuous wave EPR has been used to detect the presence of Mo5+ ions, resulting from partial reduction of Mo6+ during the melting stage and the chemical environment around Mo5+ species has been documented for the first time by pulsed EPR technique (HYSCORE). Altogether, the data contribute to a better understanding of the glass network modifications induced by the MoO3 insertion, including the non-linear evolution of the glass transition temperature that has been explained by a modification of the glass network nature.