Crystal structural refinement of corundum-structured A4M2O9 (A=Co and Mg, M=Nb and Ta) microwave dielectric ceramics by high-temperature X-ray powder diffraction

Large-scale synthesis of single-crystalline KNb3O8 nanobelts via a simple molten salt method

“…[1][2][3][4][5]. Among these complex oxides, potassium triniobate (KNb 3 O 8 ) with unique layered structures has excellent photochemical and semiconductor properties, which could have applications in photocatalyst and luminescence fields [6][7][8].…”

Improvements in the sintering behavior and microwave dielectric properties of Mg4Nb2O9 by adding Fe2O3

“…Several corundum-structured A 4 B 2 O 9 (A = Co and Mg, B = Nb and Ta) had been reported due to their excellent microwave dielectric properties [1,[9][10][11][12][13]. Among these materials, Mg 4 Nb 2 O 9 was investigated to possess a dielectric constant ε r of ∼12.4, a temperature coefficient of resonant frequency f of ∼−70 ppm/ • C and in particular, a high Q × f of ∼194,000 GHz [13].…”

Optoelectronic investigation of corundum Mg4Nb2O9 single crystal

“…The MgO 6 octahedron connected MgO 6 octahedron by sharing faces and edges with the other MgO 6 octahedron. The NbO 6 octahedron connected NbO 6 octahedron by sharing faces and connected MgO 6 octahedron by sharing edges [18,19]. The face-shared NbO 6 is the key contributor in the energy band structure and the refractive indices mainly relate to the 2p and 4d orbitals in O 2-and Nb 5+ , respectively [20,21].…”