Mechanosynthesis of the ferroelectric materials Ba2ANb5O15 (A=K, Na, Li)

Mechanochemistry: opportunities for new and cleaner synthesis

“…They have been used to synthesise several potentially important materials for applications. The carbonate method has been used to synthesize Ba 2 ANb 5 O 15 (A=K, Na, Li), 96 while simple combination of oxides allowed the synthesis of Bi 4 Ti 3 O 12 , 97 both of which are ferroelectric compounds, with potential use in memory devices. Mechanochemical methods have been used to synthesis solid state electrolytes (silver niobium oxyfluoride and silver molybdenum oxyfluoride), 98 fast ion conductors (RbAg 4 I 5 and KAg 4 I 5 Á) 99 and a lithium battery cathode material (Li 2 Mn 2 O 4 ).…”

The formation of a carbonato complex during the mechanochemical treatment of a Na2CO3–Nb2O5 mixture

“…A large number of complex compositions, prepared either directly by mechanochemical synthesis or by annealing mechanochemically activated powders, can be found in the literature [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. In most cases a starting mixture of oxides is used.…”

“…In most cases a starting mixture of oxides is used. However, it turns out that carbonates are also used at least as one of the starting compounds in the mechanochemical synthesis of many important ferroelectric and piezoelectric materials with the perovskite, tungsten bronze and Aurivillius-type structures, such us BaTiO 3 [6][7][8][9][10], (Ba x Sr 1−x )TiO 3 [11], (K x Na 1−x )NbO 3 [12], Ba 2 ANb 5-O 15 (A = K, Na, Li) [13], Bi 4 Sr n−3 Ti n O 3n+3 (n = 4.5) [14] and (Bi 2 SrNb 2 O 9 ) 1−x (Bi 3 TiNbO 9 ) x [15]. To the best of our knowledge, there has been no such study performed that could give us a better understanding of the mechanisms involved during mechanochemical synthesis in which carbonates and oxides are used as starting compounds.…”