Long-Term Hydrogen Detection Using a Hetero-Core Optical Fiber Structure Featuring Au/Ta2O5/Pd/Pt Multilayer Films

We introduce a Pt-coated, hetero-core, optical fiber-surface plasmon resonance (SPR) hydrogen sensor featuring layers of Au/Ta
₂
O
₅
/Pd for long-term hydrogen detection. Hydrogen sensing persisted after 1- and 2-month storage at room temperature in air conditioning. To test the effect of Pt coating, sensors coated with Au and Pd-only-based optical fiber hydrogen sensors were prepared. Sensors coated with a thin Pt film were superior to sensors coated with Au/Ta
₂
O
₅
/Pd or Au/Ta
₂
O
₅
/Pd/Au multilayer films with respect to the suppression of sensor sensitivity- and response time deterioration.