Luminescent properties of K2SbF5: Ln (Ln = Eu3+, Tb3+, Er3+) obtained by a facile room temperature mechanochemical synthesis

Mechanochemical synthesis of K2SbF5 by the successive grinding reactions of antimony (III) acetate with ammonium fluoride and potassium fluoride has been carried out. Powder X-ray diffraction pattern of K2SbF5 was refined successfully in orthorhombic space group (Cmcm) with a = 6.3214 (29) angstrom, b = 13.9380 (60) angstrom and c = 6.5817 (28) angstrom. Finger print vibrations of SbF52- units in the sample have also been confirmed from FT-IR and Raman spectra. 5 mol% of Eu, Tb and Er doped K2SbF5 have been synthesized by the same method and their optical properties have been analyzed. The Judd-Ofelt (J-O) parameter (Omega(J)) analyses of Eu doped samples have been carried out. On irradiating Er3+ doped sample with 980 nm laser, a bright green emission visible to the naked eye was evident. The decay times of these emissions have been estimated. Following a similar procedure, Rb2SbF5 has been synthesized for the first time.