We developed nanofols structures Al / NFSi / p-Si / Al with undecorated silicon nanowires and decorated for producing a hydrogen gas sensor.

The characteristic I (V) of the reference structure Al / NFSi / p-Si / Al does not exhibit significant variation with respect to various concentrations of H2 gas.

 It was also observed that the characteristics I (V) Pd and Au decorated structures are similar to those of the ohmic structures unlike decoration Ag and Pt which have schotky structures.

However, we found that the reference sample, ie undecorated structure and decorated structures respectively by Ag and Pt have a rectifier nature, changes in the reverse current is relatively low compared to any variations to the current Direct.

  The biggest change compared to the pressure of H2 gas is observed for decoration with the Pt. However, this change is not significant for the reverse current, which decreases as the concentration of H2 increases.

The response time required for I (t) of the sensor to reach 67% of the variation in current from the opening of the throttle, and the  recovery time to reach 67% of the variation in current from the closing the gas.

The lowest response time 46.01s and 56.11 s and 76.28 s recovery time of 56.38 s and were observed for the decorated structure for H2 at respective concentrations of 15 ppm and 85 ppm.

 The lowest response time of 54.3 s and 40.79 s recovery time was obtained for the structure Ag decorated to the highest concentration of H 2 (174 ppm), however, the time and answers highest recovery were recorded for the decorated structure Pt and this for all the H2 concentrations.

  The response and recovery time relatively short decorated Au and Ag structures can be attributed respectively to the high rate of adsorption and desorption of H2 gas.