Boron nitride nanotubes (BNNTs) decorated Pd-ternary alloy (Pd63·2Ni34·3Co2.5) for H2 sensing

The micro-electro-mechanical system (MEMS)-based field effect transistor (FET) sensor for hydrogen detection was fabricated by modifying the gate electrode with boron nitride nanotubes (BNNTs) decorated Pd-ternary alloy (Pd63·2Ni34·3Co2.5) as a hydrogen sensing layer Electro-thermal properties of the micro-heater embedded under sensor membrane were analyzed by a finite element method (FEM) simulation. The structural and morphological properties of the gate electrode were studied by Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FESEM). A variation in gate potential is observed due to the H2 atmosphere that leads to the variation in the depletion region, therefore, changing the current in the channel (BNNTs decorated Pd-ternary alloy). The BNNTs-decorated Pd ternary alloy displayed high sensing response, fast response and recovery time for H2 gas, low power consumption, long-term stability, and wide detection range from 1 to 5000 ppm H2. The drain current of the H2 FET sensor varied significantly at hydrogen gas exposure and increased with H2 concentration. As proposed H2 FET sensor can be utilized to the H2 leak detection system for safe applications.