Bismuth-Containing Glassy Reference Materials for Establishing the Content of Transition Elements Using Luminescent-Based Methods

Abstract

Modern express methods of analytical control are widely used for monitoring the quality of oxide materials. However, the possibilities of these methods are currently limited by the lack of versatile homogeneous reference materials (RMs). Such RMs can most effectively be produced by vitrification methods. In this connection, glassy RMs based on bismuth-borate systems are of great interest. In earlier research, bismuth-borate RMs were used for comparison purposes in determining the composition of complex oxide systems using the X-ray fluorescence method. In this work, we consider issues associated with the synthesis and application of bismuth-borate glassy RMs for determining the content of transition elements in oxide compounds and mixtures using luminescence analysis. Luminescence analysis was used as a research method due to its high selectivity and low detection limits with respect to elemental impurities in controlled objects (usually constituting 1 × 10⁻⁶–1 × 10⁻⁴ wt%). Bismuth-borate glassy RMs are shown to be capable of luminescence under UV radiation in the visible range at a temperature of 77 K. It is established that the introduction of the oxides of transition and rare earth elements (REE) into the RM composition leads to the quenching of the exciton emission band in the studied glasses at 77 K, as well as to the appearance of bands typical of REE ion radiation both at 77 and at 298 K. Glassy RMs doped with transition-element oxides are found to quench the luminescence of both bismuth and REE ions at a temperature of 77 K. On the basis of the results obtained, measurement procedures for determining the content of quenching elements in oxide materials have been developed. The metrological characteristics of these procedures have been evaluated.