Preparation of Potassium Tantalate Niobate by Sol–Gel Method

Perovskite potassium tantalate niobate (KTN) powders and thin films were synthesized from a metal alkoxide solution. Homogeneous KTN coating solutions were prepared from KOC 2 H 5 , Ta(OC 2 H 5 ) 5 , and Nb(OC 2 H 5 ) 5 in absolute ethanol. The precursor crystallized to pyrochlore at ∼ 650°C, and then to perovskite at ∼ 750°C, depending upon Ta:Nb ratio. H 2 O vapor during calcination was found to play a prominent role in the direct and predominant crystallization of perovskite films with preferred orientation. Highly oriented KTN films of perovskite structure were successfully prepared on MgO (100) substrates at 675°C.