High sensitivity graphite-Pd (Pt) nanoparticles-InP Schottky diode hydrogen sensor

Hydrogen sensing characteristics of graphite-Pd(Pt)/InP Schottky diodes fabricated by electrophoretic deposition technique were investigated. The proposed hydrogen sensors showed relatively high sensitivity response of ~10
⁶
to 1000 ppm H
₂
in N
₂
. The barrier height reduction due to hydrogen exposure was 0.35 eV and 0.37 eV for Pd and Pt based Schottky diodes respectively. Temperature dependence of the sensitivity, the barrier height variation, the ideality factor and the barrier height itself were studied. Pt based Schottky diodes show better sensitivity and shorter recovery times compared to Pd ones.