Anodization formation of through-hole nanoporous layers on TixNb1−x (x = 0.3–0.7) alloys in nitric acid electrolytes

Self-organized, through-hole, and ordered nanoporous array layers are obtained by anodizing TixNb1−x (x = 0.3–0.7) alloys in nitric acid electrolytes by a rapid, direct, and exothermal method. The TiNb oxide nanoporous films consist of straight and uniform pores of diameters 10–30 nm, and the back side has uniform pores of diameters 20–60 nm. The pore spacing increases with increasing Nb content and nitric acid concentration. The process is remarkably reliable and reproducible.