Partially agglomerated metallic thin films deposited on ceramic substrates represent an important component of the electrode-electrolyte system in various solid-state electrochemistry applications, such as gas sensing or solid oxide fuel cells. In particular, the electrochemical reaction usually occurs at the triple lines where the metal contact, solid electrolyte and gas meet together. Therefore, the total length of these triple lines should be maximized for improving the electrochemical performance of the system.
In this study, we propose a novel method of manipulating the total length of the triple lines in partially agglomerated metal thin films deposited on ceramic substrates. First, the solid solution nanoparticles have been fabricated employing the dewetting phenomenon. Then, a pure metal layer was deposited on the particles followed by annealing at low homological temperature. During this annealing, the material of the film diffuses into the particles, which accelerates the grain boundary grooving and dewetting processes and results in high area density of holes in the film.
The mechanism of this alloy-accelerated dewetting that was studied employing scanning electron microscopy and a combination of focused ion beam with transmission electron microscopy.