Large permittivity, low loss and defect structure in (Nb, Zn) co-doped SnO2 ceramics studied through a combined experimental and DFT calculational method

作者：Tan, Yu; Wang, Heng^*; Wang, Yushi; Ren, Yaru; Wen, Jianfeng; Ma, Jiafeng; Ma, Yiping; Xu, Dinghui; Yue, Yuanfang; Wang, Bin

来源：Ceramics International, 2023, 49(13): 21402-21410.

DOI：10.1016/j.ceramint.2023.03.269

• SnO2
• Permittivity
• Oxygen vacancy
• Defect dipoles
• DFT calculation

Dielectric ceramics with high permittivity and low loss are widely used in electronic components and devices. In this study, (Nb, Zn) co-doped NbxZnySn(1-x-y)O(2) with different doping levels and Nb/Zn ratios was designed to tune the defect structure toward the optimal dielectric performance. The lattice parameters firstly increased from x = y = 0.01 to 0.03 and then decreased, while the oxygen vacancy concentration decreased with doping. The codoped sample with x = y = 0.02 exhibits stable permittivity up to 800 with an ultra-low loss tan delta similar to 0.03 at 40 Hz. DFT calculation showed that the oxygen vacancy was formed with single-Zn doping and co-doping at low doping level, while the hole was generated at higher doping level. The achieved large permittivity and low loss of the sample are related to both Electron-Pinned Defect Dipoles (EPDD) and Hole-Pinned Defect Dipoles (HPDD) effects in the lattice, which was determined by the relative positions of donor and acceptor dopants.

• 单位
  桂林理工大学