Fast hydrogen-induced optical and electrical transitions of Mg and Mg-Ni films with amorphous structure

Amorphous Mg and MgNix (x = 0.03–0.30) films were prepared and their optical and electrical transitions upon hydrogen loading/unloading at room temperature were investigated. The results show that amorphous films have faster optical and electrical transitions than corresponding crystalline ones. Amorphous structure greatly facilitates hydrogen diffusion, resulting in not only preventing the formation of blocking hydrides layers but also changing the rate-controlling step from hydrogen diffusion for crystalline film to the reaction between hydrogen and Mg and/or Mg-Ni phases. We envision that amorphization is generally applicable to improve hydrogen-induced response characteristics of switchable mirror thin films.

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