Ceramic–electrode inter-diffusion of (K, Na)NbO3-based multilayer ceramics with Ag0.7Pd0.3 electrode

The (K, Na) NbO3 (KNN) based multilayer ceramics with Ag0.7Pd0.3 inner electrode were fabricated by tape casting and cofiring processes. The ceramic–electrode inter-diffusion was studied by an energy dispersive X-ray spectroscopy with a precise spacial resolution attached to a transmission electron microscope. The results showed that the inter-diffusion occurred with elements migration through an interface zone. The distinct lattice image of the ceramic–electrode interface was obtained by a high-resolution transmission electron microscope. The lattice of KNN ceramic and Ag/Pd alloy interlaced with each other along the interface with slight lattice distortion. The results showed that the ceramic–electrode interface was very sharp with a width of about 5 nm. The sharp interface is good for the KNN-based multilayer ceramics with Ag/Pd electrode to be applied as promising substitutes for lead-based multilayer ones.