A Method to Control Palladium Crystallographic Texture and Surface Morphology
Cube Textured Palladium Substrate Fabrication
The evolution of a material's surface morphology during anisotropic wet chemical etching is dependent on the starting material’s surface texture. Thus, single crystal materials are desired to achieve reproducible etch morphologies in order to study catalytic activities. However, the methods to produce single crystals are cost intensive. To overcome this issue, cold rolling has been investigated to produce quasi-single crystal material, the details of which are currently lacking for the fabrication of such Pd substrates. The factors that affect the the development of crystallographic texture are: grain size distribution, and rate of recrystallization. We developed a procedure that includes rolling, annealing, oxidation and etching to produce foils with desired crystallographic texture, surface morphology and strong grain boundary grooving, Finally, supplementary density functional theory (DFT) surface free energy calculations provide the explanation of the experimentally observed anisotropic etch results.