Structures and dielectric properties of (Nb, Zn) co-doped SrTiO3 ceramics at various sintering temperatures

Manipulating the carrier concentration and phase transition via Nb content in SrTiO3

“…It verifies our previous analyses form the XRD, rocking curve and RMS data: Nb doping introduce lattice distortion, lattice expansion, point defects and stacking faults which breaks the local symmetry of the single crystals. Moreover, another very weak scatter peak appeares around 871 cm −1 , which has been observed in other doped STO and is believed to result from the incorporation of impurity ions in B sites and the distortion of oxygen octahedron 24 , 48 . As the doping concentration of Nb element gets higher the intensity of second-order features gets weaker and sharp peaks at 144 and 444 cm −1 generates at 110 K, indicating the weaken of the cubic structure and the formation of the tetragonal structure.…”

Defect chemistry of A site nonstoichiometry and the resulting dielectric behaviors in SrxTi0.985(Nb2/3Zn1/3)0.015O3 ceramics

“…The anisotropic g factors of Ti 3+ ion and oxygen vacancy also indicate the changes in local structural symmetry of the ceramics. Besides, the peak at g = 2.003 is obviously broadened, underlying that the relaxation time of electron becomes longer due to the presence of defect cluster, 34 which can be further confirmed by TSDC technique. The depolarized current of x = 0.98 ceramics under different polarization electric fields are shown in Figure 6B.…”

“…Figure 4B features the fitting result of O 1 s peak. The peak around 529.3 eV is ascribed to lattice oxygen (O L ), and the shoulder peak around 531.1 eV can be attributed to non‐lattice oxygen (O N ), including oxygen vacancies, chemical adsorbed oxygen, surface H 2 O and hydroxyl 34 . The corresponding proportions between O N and O L are illustrated in the inset.…”

A unique octadecahedron SrTiO3 perovskite oxide with a nano step-shaped facet structure for enhanced photoredox and hydrogen evolution performance

“…18 In addition, the peak at g = 2.003 for Step-STO-SSR was distinctly broadened, indicating that the crystal defects lead to a longer electron relaxation time. 31 Consequently, the formation of O V –Ti 3+ pairs brings about an easier electron transfer behavior and enhanced the redox ability of strontium titanate. In addition, Zhu et al 32 found that annealing SrTiO 3 at 1100 °C with Sr 3 Ti 2 O 7 , that is, under the Sr-rich condition, the photoredox properties of some (110) facets can be changed from photooxidation to photoreduction, and the (110) facets become the bifunctional crystal facet.…”