Color-neutral switchable mirrors based on magnesium-titanium thin films

In an investigation of smart-window applications of switchable mirror thin films, Pd-capped magnesium-titanium thin films were prepared by dc magnetron sputtering. Their optical properties, switching durability and crystalline structures have been investigated. We show that Pd/Mg-Ti thin films with specific thicknesses are completely color-neutral in the transparent state and their optical switching properties are suitable for building and automobile window glass applications. The ternary hydrides of Mg_(1-x)Ti_x thin films with Pd overlayers are identified by in situ X-ray diffraction measurements during a hydrogen gas loading of 4%. Pd/Mg_(1-x)Ti_x thin film switchable mirrors show fast hydriding and dehydriding kinetics as compared to a Pd-capped pure Mg thin film due to the catalytic role of doped metallic Ti. PACS 75.20.En; 78.20.-e; 78.70.Ck; 42.70.-a