Microstructure and polarization of La0.8Sr0.2MnO3 cathode deposited by alcohol solution precursor plasma spraying

Current Progress in Solution Precursor Plasma Spraying of Cermets: A Review

“…Unlike the aqueous solution, microstructures with mostly-crystallized perovskite phases were observed in LSM coatings when using ethanol as the solvent [29]. In another work, the production of zinc ferrite coatings using organic solvent exhibited an impurity phase (Fe 2 O 3 ) unlike using aqueous solution, as shown in Figure 4 [10].…”

“…The chemistry of solution precursors, their concentration and solvent used, determine the characteristics of the resulting coatings [10,[22][23][24][25][26][27][28][29]. The spraying process is accompanied by the decomposition of the precursor at the elevated temperature and high heat transfer of the plasma jet [10,[22][23][24][25].…”

“…Solutions having low-concentration precursors generally experience surface precipitation leading to the formation of shells, while a highly-concentrated solution experiences volumetric precipitation leading to fully-melted splat microstructures. In order to induce volumetric precipitation, solution concentration must be near the equilibrium saturation concentration [17,[27][28][29][30]. With these, high concentration solution precursors are used to deposit dense coatings.…”

“…The choice of solvent in the solution preparation is also important in the coating deposition as it relates to the ionic interactions at the molecular level due to macroscopic solvent properties, such as viscosity, surface tension, etc., and could modify the plasma jet's thermodynamic and transport properties which directly affect the splat formation (see Table 2) [10,24,[28][29][30]. Aqueous solution precursor feedstock is prone to produce larger droplet size due to its high surface tension affecting the droplet breakup.…”

“…On the contrary, when ethanol was employed as solvent, LSM cermets had a porous morphology with a large number of agglomerated small particles (0.2 to 2 µm) [29]. Unlike the aqueous solution, microstructures with mostly-crystallized perovskite phases were observed in LSM coatings when using ethanol as the solvent [29].…”