Synthesis, crystal structure, and characterization of Na2SrV4O12: A low‐firing dielectric vanadate. Issue 6 (9th February 2023)

• Record Type: Journal Article
• Authors: Li, Chunchun; Meng, Yingzhi; Hou, Hongping; Zhang, Amei; Khaliq, Jibran; Liao, Na; Fu, Caixia; Liu, Laijun; Du, Hongliang
• Is Part Of: Journal of the American Ceramic Society. Volume 106:Issue 6(2023)
• Page Start: 3501
• Page End: 3508
• Publication Date: 2023-02-09
• Subjects: ceramics -- dielectric properties -- low‐temperature firing -- vanadate; Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.19019
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract: In this work, cyclotetravanadate Na2 SrV4 O12 was synthesized at a relatively low sintering temperature of ∼500°C using a solid‐state reaction method. X‐ray diffraction and a transmission electron microscope characterization featured a tetragonal structure that was built by a 3D frame of isolated tetracyclic (V4 O12 ) 4− . Dielectric measurements demonstrated strong dependence on frequency and temperature. A low relative permittivity of εr ∼ 8 ± 0.2 and a dielectric (loss tan δ ) ∼ 0.4 ± 0.01 was achieved at a frequency of 10 kHz and room temperature. ac impedance and conductivity analysis revealed a thermally activated migration behavior of charge carriers with a short‐range hopping feature. XPS analysis validated the existence of oxygen vacancy and reduction in vanadium (from V 5+ to V 4+ ), which gave rise to charged lattice defects. The migration or hopping of such charged defects was responsible for the observed electrical behaviors. Owing to the simple composition, inexpensive raw materials and low density (2.99 g/cm 3 ) make Na2 SrV4 O12 ceramic a potential candidate for lightweight devices and in photocatalytic degradation and all‐solid‐state ion batteries.