Niobium-oxygen octahedra and oxygen interstitial defect emissions in calcium niobate matrix and its color manipulation via doping Pr3+

Abstract

The luminescent properties of Ca2Nb2O7 matrix and Ca2Nb2O7: Pr3+ were studied in this work. In addition to the emission band from NbO6 octahedra, the orange-red emission aroused by oxygen interstitial defects was observed in Ca2Nb2O7. When Pr3+ was introduced, both of the matrix emission and the characteristic Pr3+ luminescence could appear simultaneously under suitable excitation wavelength. By further adjusting the doping concentration, color manipulation from blue-green to pink and red could be realized in Ca2Nb2O7: Pr3+. In particular, a warm white light could be achieved when doping 0.1% Pr3+. Based on the luminescent results, the underlying mechanisms were discussed and proposed. The color manipulation results suggest that Ca2Nb2O7: Pr3+ is promising for various fields related to lighting, displaying, and imaging.

Creating dual-mode luminescence in piezoelectric calcium niobates through lanthanide-doped for anti-counterfeiting and temperature sensing

“…These absorption bands can be assigned to the transitions of Pr 3+ : 3 P2,1,0, 1 D2→ 3 H4 and Er 3+ : 2 H11/2→ 4 I15/2 [31]. The results indicate that the doped praseodymium ions produced local energy levels within the bandgap of calcium niobate matrix [32]. According to the measured reflection spectra, the band gap width of these specimens was calculated and shown in Fig.…”

Phase states, microstructure and dielectric characteristics of solid solutions (1 – x)NaNbO3 – xCa2Nb2O7 and (1 – x)NaNbO3 – xSr2Nb2O7

“…Ferroelectrics Ca 2 Nb 2 O 7 (CN) and Sr 2 Nb 2 O 7 (SN) are representatives of this class of materials and currently being considered as the basis for many applications. CN is considered as a promising compound for non-linear optics [3], laser technology [4], highly active photocatalyst for water splitting [5,6], design a multifunctional optical storage device [7,8]. Both the CN and SN demonstrate mild piezoelectric properties (d 33 < 10 pC/N) with extremely high Curie temperatures (~1800 K and 1600 K, respectively) [9,10].…”

“…This suggests that CN and SN can found broad application in the aerospace, automotive, and power generating industries [1,10]. In the past years, appreciable attention has been given to enhance properties of the PLS ferroelectrics by modification [4,13,14,15] and creating new solid solutions [16,17,18]. In this work samples of the binary systems solid solutions (1x)NaNbO 3 -xCa 2 Nb 2 O 7 (NCN) and (1x)NaNbO 3 -xSr 2 Nb 2 O 7 (NSN) were the objects of study.…”

Intercalation of water molecules from the air into perovskite and layered structures formed in the system of NaNbO3–Ca2Nb2O7

“…Calcium pyroniobate is a ferroelectric with a Curie temperature above 1800 K [2]. It is considered as a promising compound for non-linear optics [3] and laser technology [4]. In addition, Ca 2 Nb 2 O 7 is a highly active photocatalyst for water splitting under UV light irradiation [5, 6].…”