The relationship between enhanced dielectric property and structural distortion in Ca doped Ba2NaNb5O15 tungsten bronze ceramics

Relaxor Nature and Energy Storage Properties of Sr2–xMxNaNb5–xTixO15 (M = La3+ and Ho3+) Tungsten Bronze Ceramics

“…When C-sites are completely empty, if the A-sites are partially occupied, it can be described as unfilled, such as Sr 1−x Ba x Nb 2 O 6 ; 15 otherwise, it is described as filled, such as Ba 2 NaNb 5 O 15. 16 The situation where the A-site and the C-site are all occupied is described as fully filled, which is rarely the case because the small size of the C-site allows only limited ions to enter. 17,18 The unequal substitution of A and B positions provides a broad free degree for the composition design and performance improvement of TTB.…”

“…21,22 Sun et al prepared Ca-doped Ba 2 NaNb 5 O 15 ceramics and obtained an energy storage density of 0.83 J/cm 3 and an efficiency of about 75%. 16 Yang et al achieved a density of 0.11 J/cm 3 and an efficiency of 63.8% in (Ca 0.28 Ba 0.72 ) 2.1 Na 0.8 Nb 5 O 15 -based ceramics through B-site substitution. 23 poor relaxation, it is difficult for TTB to achieve high energy storage density and efficiency at the same time.…”

“…When C-sites are completely empty, if the A-sites are partially occupied, it can be described as unfilled, such as Sr 1– x Ba x Nb 2 O 6 ; otherwise, it is described as filled, such as Ba 2 NaNb 5 O 15. The situation where the A-site and the C-site are all occupied is described as fully filled, which is rarely the case because the small size of the C-site allows only limited ions to enter. , The unequal substitution of A and B positions provides a broad free degree for the composition design and performance improvement of TTB. The electrical properties of TTB, such as piezoelectric and second harmonic, have been widely studied. , As an energy storage dielectric, TTB has seen relatively little research. , Sun et al prepared Ca-doped Ba 2 NaNb 5 O 15 ceramics and obtained an energy storage density of 0.83 J/cm 3 and an efficiency of about 75% .…”

“… The situation where the A-site and the C-site are all occupied is described as fully filled, which is rarely the case because the small size of the C-site allows only limited ions to enter. , The unequal substitution of A and B positions provides a broad free degree for the composition design and performance improvement of TTB. The electrical properties of TTB, such as piezoelectric and second harmonic, have been widely studied. , As an energy storage dielectric, TTB has seen relatively little research. , Sun et al prepared Ca-doped Ba 2 NaNb 5 O 15 ceramics and obtained an energy storage density of 0.83 J/cm 3 and an efficiency of about 75% . Yang et al achieved a density of 0.11 J/cm 3 and an efficiency of 63.8% in (Ca 0.28 Ba 0.72 ) 2.1 Na 0.8 Nb 5 O 15 -based ceramics through B-site substitution .…”

Achieving ultrahigh discharge energy and power density in niobate-based glass ceramics via A-site substitution modulation during crystallization

“…26,27 When the cation with a smaller radius was introduced at the A-site, the polarizability of the A-site cation can be improved and the unit cell will shrink at the same time, which is helpful to enhance dielectric and ferroelectric properties. 28–30 Meanwhile, considering the effectiveness of defect modulation combined with the polar nano-domain engineering strategy for optimizing energy storage performance of ceramics, it is reasonable for glass ceramics with tungsten bronze structure nano-crystals that A-site defect modulation via introducing ions with a smaller radius into precipitated nano-crystals will also play an important role in improving energy storage performance based on the appropriate parent glass composition and fine modification of the crystallization process.…”