Zirconium/silver alloy foil (~ 1wt% Ag, 0.1 mm thickness, HMW Hauner) before electrochemical anodization was ultrasonicated in acetone, ethanol, and deionized water for 10 min each and dried in N 2 . The anodization was done using a high-voltage potentiostat (Jaissle IMP 88 -200 PC) with an electrochemical cell consisting of a circular working area of 1 cm 2 and a platinum counter electrode in a typical two-electrode setup. The organic electrolyte used in this experiment is based on the previous work of Vakamulla et al. and contains 2 wt% NH 4 F (Sigma Aldrich), 1 wt% H 2 0, and 30 % formamide (Carl Roth) in glycerol (Carl Roth) . The Zr-Ag alloy was anodized for 1 h at 90 V, constant voltage after gradual ramping from OCP in 60 s. The current density and voltage during anodization were recorded and monitored by the ECM-Win software. The as-anodized ZrNT/Ag 2 O/AgNp nanotubes were rinsed with deionized water and soaked in ethanol for 10 mins to dissolve remains from the organic electrolyte and then dried in N 2 . The nonmodified ZrNT arrays were prepared using Zirconium foil with the same anodization steps.