“…In comparison with thermo-electric (TE) materials containing elements such as Cd, Tl, Se, Te, Sb, Bi, the TE-oxides of alkali, alkali earth, and transition elements are generally cheaper and more health and environmental friendly, and the abundance of their constituent elements on Earth's crust is orders of magnitude higher. Among them, strontium barium niobates, SrxBa1-xNb2O6 (SBN) are interesting because of their low thermal conductivity, which is related to structural features [1,2] Actually, SBNs have been investigated since long time not only as TE materials [4][5][6][7][8][9][10], but also for ferro-electricity [11][12][13][14][15][16][17][18][19] , dielectric properties [20][21][22][23], photocatalysis [24,25], and photorefractive, electro-optic, nonlinear optic, and fluorescence properties [26][27][28][29][30][31][32]. The structural aspects and their relation with the functional properties have been comprehensively discussed by Zhu et al [18] using a crystal-chemical model for the whole family of tetragonal bronzes.…”