Elaboration of lead-free Na 0.5 Bi 0.5 TiO 3 –BaTiO 3 (NBT-BT) thick films by aerosol deposition method (ADM)

Abstract

a b s t r a c tThick and dense ceramic films of lead-free 0.94Na 0.5 Bi 0.5 TiO 3 -0.06 BaTiO 3 (NBT-BT) composition were elaborated by aerosol deposition method (ADM) at room temperature. A powder of suitable grain size was elaborated by solid state reaction. Using this powder, two samples were elaborated by ADM respectively on glass and metallic substrates, in order to check for microstructure and electrical properties. This process allowed obtaining a thick film (3.2 mm) with dense microstructure. Measurement of electrical properties revealed a lossy dielectric behavior indicating interfacial phenomena at the electrodefilm interface. The measurement of the ferroelectric hysteresis cycle does not show any characteristics of a ferroelectric behavior, but corresponds well to the one of a lossy non-linear dielectric. The absence of ferroelectricity is probably due to the low grain size of the obtained thick film (130 nm). Further experiments are in progress in order to try to obtain ferroelectric properties.

Temperature‐induced changes of the electrical and mechanical properties of aerosol‐deposited BaTiO3 thick films for energy storage applications

“…In contrast to cold spraying, the AD process is based on deposition in vacuum conditions, significantly enhancing the applicability of ceramic starting powders 11,17,18 . In terms of polar dielectric ceramics, the AD method has been successfully employed to fabricate ferroelectric thick films, for example, lead‐free BaTiO 3 (BT), 2 (K 0.5 Na 0.5 )NbO 3 (KNN), 19,20 and 0.94Na 0.5 Bi 0.5 TiO 3 –0.06BaTiO 3 (NBT–6BT), 21 as well as lead‐based Pb(Zr,Ti)O 3 (PZT) 22,23 and Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 (PMN–PT) 24 on different substrates, such as ceramic, glass, and metal. Compared to bulk ceramics, dielectric permittivity and resistivity are significantly reduced in as‐processed AD films.…”

Dielectric, ferroelectric and optical properties of Na and Nb co-doped (Bi0.5Na0.5)0.94Ba0.06TiO3

“…Their resulting solid solution shows high and stable permittivity, low conduction losses or dielectric losses under a very high temperature range [12]. Temperature dependent electrical properties of lead-free 0.94(Bi0.5Na0.5TiO3)-0.06BaTiO3 ceramics have been investigated [13]. At temperature below 100 °C, a transition from rhombohedral to tetragonal phase shows dominant FE order and as temperature reaches to 100 °C, the antiferroelectric (AFE) order prevails.…”