Molten chloride synthesis, structural characterisation and luminescence spectroscopy of ultrafine Eu3+-doped BaTiO3 and SrTiO3

Green and red upconversion luminescence in Er3+-doped and Er3+/Yb3+-codoped SrTiO3 ultrafine powders

“…SrTiO 3 (STO1), SrTiO 3 :Er (1%) (STO2) and SrTiO 3 :Er (1%) + Yb (1%) (STO3) powders were prepared in a molten NaCl flux [17]. Appropriate quantities of TiO 2 , SrCO 3 , Er 2 O 3 , Yb 2 O 3 and NaCl were mixed and heated in a crucible at 1000 • C for 3 h, and then cooled quickly to room temperature.…”

Photoluminescence investigations of Eu3+ doped BaTiO3 nanopowders fabricated using heterometallic tetranuclear alkoxide complexes

“…All spectra are dominated by the 5 D 0 → 7 F 2 electron transition, called the hypersensitive forced electric dipole emission, which is here much stronger than 5 D 0 → 7 F 1 magnetic-dipole emission. It must be mentioned that the emission of the synthesized final product via this technique in case of all samples was weaker than in material prepared using sol-gel method [14][15][16], prob- Table 1 Selected bond lengths (Å) and angles ( • ) for Ba 2 Ti 2 (thd) 4 (O n Pr) 8 ( n PrOH) 2 ably due to the lower crystallization degree (see XRD patterns) OH − content and higher concentration of defects induced by the charge compensation mechanism due to the addition of Eu 3+ [17,18]. One can note that the emission spectra differ with the temperature of annealing.…”

“…It has become clear at this moment that the control of stoichiometry, crystal structure and morphology for this particular phase represents a considerable challenge [3]. The further studies of the composition and structure of the applied sol-gel precursors revealed that solutions of homoleptic alkoxide complexes turned to contain precursors with compositions deviating from 1:1 (BaTi 4 (OR) 18 , Ba 2 Ti(OR) 8 (ROH) 4 , etc. [4]) or oxoalkoxide complexes demonstrating rather limited solution stability [5].…”

Catalytic combustion of soot particulates over rare-earth substituted Ln2Sn2O7 pyrochlores (Ln = La, Nd and Sm)

“…In general, the amount of oxygen vacancy is associated with the intensity of the emission spectrum. A lower luminous intensity is presumably due to the higher concentration of defects [26,37]. It can be seen from Fig.…”