Flame spray deposition of nanocrystalline dense Ce0.8Gd0.2O2 − δ thin films: Deposition mechanism and microstructural characterization

Nanocrystalline dense sub-micron thin films of Ce0.8Gd0.2O2 − δ have been successfully deposited by flame spray deposition. The deposition mechanism has been identified as droplet deposition. The deposition temperature of the substrate was as low as 200 °C and the deposition rate ∼ 30 nm/min. Under these conditions the droplets have a very limited residence time in the hot zone of the flame and are deposited as liquid, forming smooth films free of particles. They exhibited a dense and crack-free microstructure. Grain growth, lattice constant, crystallographic density and surface roughness have been investigated as a function of annealing temperature. The good quality of the films, in association with the high deposition rates at low deposition temperatures shows the preeminence of the flame spray method for depositing thin films for micro-solid oxide fuel cells.