Results and discussion
X-ray powder diffraction studies
Fig. 1. X-ray diffraction (XRD) patterns of Tb2(MoO4)3 phosphor samples obtained after annealing at different temperature for 2 h.Figure optionsDownload full-size imageDownload as PowerPoint slide
The crystallite size can be assessed by the Scherrer equation, D = Kλ/β cos θ, where D Amlodipine the average crystallite size, λ is the X-ray wavelength (1.5406 Å), β is the full width at half maximum (FWHM) and θ is the diffraction angle. The strongest diffraction peak is used to calculate the crystallite sizes of the prepared Tb2(MoO4)3 phosphor annealed at 900 °C, which yielded an average size of 35 nm.
Fig. 2. TEM and HRTEM images (a and b), SAED and EDS (c and d) pattern of Tb2(MoO4)3 nanophosphor.Figure optionsDownload full-size imageDownload as PowerPoint slide
Raman spectra analysis
Raman spectra of the orthorhombic Tb2(MoO4)3 is excretion shown in Fig. 3. Considering the whole unit cell of Tb2(MoO4)3, each vibration splits into 12 modes, with 3 Raman active (3A2) and 9 both Raman and IR active (3A1 + 3B1 + 3B2) modes . The three allowed Raman bands in the spectrum were identified at 903 cm−1 (A2), 850 cm−1 (A2) and 354 cm−1 (A2). The Raman and IR active bands are observed around 960 cm−1 (A1), 942 cm−1 (A1), 201 cm−1 (A1), 327 cm−1 (B1), 150 cm−1 (B1), 102 cm−1 (B1), 821 cm−1 (B2), 746 cm−1 (B2) and 388 cm−1 (B2) respectively.