Inverse surface plasmon resonance based effective hydrogen sensing using nanoscale palladium films

摘要

We demonstrate a nanoscale palladium (Pd) based inverse surface plasmon resonance (ISPR) setup for sensing highly inflammable hydrogen (H_2) gas. The ISPR setup was employed in Kretschmann configuration to assess the sensitivity of the Pd-films when subjected to H_2 gas exposure. With an adequate broadening of the SPR peak maxima, the SPR angle was found to shift from a value of 46.57° to 50.97°, when the concentration of H_2 was varied between 0% and 0.9%. The shifting can be attributed to the transient development of isolated PdH_x (x ＜ 1) clusters within Pd lattices, resulting in an appreciable change of refractive index locally. The dynamical behaviour of switching on/off states exhibited by a ～20 nm Pd-film and exposed to 0.1% H_2 gas was monitored over several cycles repetitively. The ISPR based H_2 sensor, as demonstrated in ambient environment, would find scope to detect low level H_2 in industrial and other hazardous areas.