Nd3+ dopant influence on the structural and spectroscopic properties of microcrystalline La2Mo2O9 molybdate

• Dopant influence on structural and spectroscopic properties of Nd3+-doped La2Mo2O9.
• Comparative study for two possible types of polymorphs (monoclinic and cubic).
• Nd3+-doped monoclinic phase – potential phosphor and short pulses laser material.
• Nd3+-doped cubic phase – potential transparent ceramic for laser applications.

In this paper we report the detailed analysis of both structural characterization by XRD, DSC, Raman, SEM techniques and high resolution spectroscopic properties of microcrystalline Nd3+-doped La2Mo2O9 (LAMOX) dilanthanum dimolybdate obtained by the conventional solid state reaction. Basing on the analysis of a series of compounds with a wide range of Nd3+ ion concentration we discovered that the amount of Nd3+ dopant substituting La3+ ions affects significantly on structural and spectroscopic properties. Pure Nd3+-doped phases with monoclinic structure (α-form, the space group P21) were observed for the concentration of optically active ion up to 15%. When the concentration of Nd3+ ions is higher a cubic structure (β-form, the space group P213) starts to form. However, up to concentration of 50 mol% of the Nd3+ ion a mixture of the monoclinic and cubic phases has been observed. Pure cubic phase was obtained when the Nd3+ contents had reached 50 mol%. The spectroscopic analysis has shown that the Nd3+-doped monoclinic phase might be useful for application in the future as phosphors and ultra-short pulses (pico, femto) laser materials. The cubic phase could be useful to fabricate transparent ceramics and might be an important challenge for laser applications.