Laser-induced time-resolved luminescence in analysis of rare earth elements in apatite and calcite

Sari Romppanen,Heikki Häkkänen,Saara Kaski

doi:10.1016/j.jlumin.2021.117929

Sari Romppanen, Heikki Häkkänen + Show 1 more

Open Access

https://doi.org/10.1016/j.jlumin.2021.117929

Copy DOI

Journal: Journal of Luminescence	Publication Date: Jan 29, 2021
Citations: 3	License type: cc-by

Affiliation: University of Jyväskylä

Abstract

Laser-induced time-resolved luminescence was used to study rare earth element (REE) containing natural apatite and calcite minerals. The luminescence from 400 nm to 700 nm in the minerals was analyzed with excitation ranges 210–340 nm and 405–535 nm. As an outcome, several useful excitation wavelengths to detect one or more REE from apatite and calcite are reported. The feasibility of selected excitations in e.g. avoiding the disturbance of intense Mn2+ luminescence band, results was demonstrated with a non-gated detector.

Highlights

Rare earth elements (REEs) are representing a group of elements consisting of lanthanoids (La–Lu), yttrium (Y), and scandium (Sc)
The chosen delay and gate times seem to be suitable for observing several narrow REE3+ luminescence peaks simultaneously
Intensities of the luminescence peaks and bands in calcite were lower than in apatite, which is most likely caused by the lower REE content in calcite in the Siilinjarvi [17]

Summary

Introduction

Rare earth elements (REEs) are representing a group of elements consisting of lanthanoids (La–Lu), yttrium (Y), and scandium (Sc). REEs can act as luminescence centres in host minerals and luminescence spectroscopy is efficient in detecting them. Natural minerals typically host several REEs simultaneously [2]. Luminescence emission of REEs is generally observed as relatively sharp lines and only some ions e.g. Ce3+ and Eu2+ have broad bands [3], in natural minerals, the luminescence spectrum can be rather complex with several overlapping bands. The crystal field of the host mineral lattice can split the energy levels of REE3+ ions [3] and as a consequence, more lumi nescence emission lines may appear. The intensity of lumi nescence emission is dependent on both the mineral’s crystallinity and on the surroundings of the luminescence centre, which may change the energy transfer, quenching, reabsorption and sensitizing processes [4,5,6]

Objectives

Methods

Results

Conclusion