Optical pressure nano-sensor based on lanthanide doped SrB2O4:Sm2+ luminescence – Novel high-pressure nanomanometer

A new, non-contact optical sensor of pressure based on the SrB2O4:Sm2+ nanoparticles has been successfully synthesized via a simple and low-cost Pechini method. The obtained nanomaterial was thoroughly characterized using powder X-ray diffraction, transmission electron microscopy, and Raman and luminescence spectroscopies, including high-pressure and high-temperature extreme conditions measurements. Compression of the material leads to a significant red-shift of the intraconfigurational 5D0→7FJ (J = 0−3) emission bands, and to an increase of the Raman mode energies, whose shift rates as a function of pressure were determined. The shift of the extremely sharp and the most intense 5D0→7F0 emission band (Δλ ≈0.24 nm/GPa; Γ (FHWM) ≈0.15 nm) has been used for the determination of the pressure calibration curve. The high-temperature luminescence measurements revealed a desirably weak temperature dependence of the peak spectral position, which was included in the determined pressure calibration curve. The SrB2O4:Sm2+ nanomaterial studied exhibits a negligible temperature-induced emission lines broadening, and relative low thermal quenching of luminescence. The use of such Sm2+-based contactless pressure nano-sensor allows a very accurate pressure sensing ( ± 0.01 GPa), in the sub-micro sized regions, both at low and high temperature conditions.