Fabrication and Characterization of Titanium Dioxide Based Pd/TiO₂/Si MOS Sensor for Hydrogen Gas

Room temperature high hydrogen gas response in Pd/TiO 2 /Si/Al capacitive sensor

“…However, the production, transportation and applications of H 2 are very risky due to its inflammable and explosive characteristics [4]. The explosive nature of H 2 gas increases with concentration and become highly inflammable and explosive for concentration of ≥4% [1, 5]. Therefore, an electronic sensor is commonly used to monitor the presence or concentration of H 2 [6].…”

“…Various types of hydrogen gas sensors have been reported in the literature [5, 7–9]. Most of the gas sensors use transition metal oxides as active sensing material in the device [4, 7, 10].…”

“…The MOS‐based sensors have a unique advantage over other sensors such as catalytic combustion type or chromatography‐based sensors. MOS sensors have high sensitivity, fast response and recovery times [5, 13]. Large‐area MOS sensors can be easily fabricated by using various deposition techniques such as the thermal evaporation, sputtering, electron beam evaporation, hydrothermal, chemical vapour deposition, sol–gel, etc.…”

“…Different oxide materials namely tin oxide (SnO 2 ), zinc oxide (ZnO), titanium oxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), bismuth oxide (Bi 2 O 3 ), cobalt oxide (CoO), gallium oxide (Ga 2 O 3 ), indium oxide (In 2 O 3 ), tungsten oxide (WO) and nickel oxide (NiO) are explored in the literature for possible applications in various gas sensors [16]. The response of most of the metal oxides based thin film sensors is poor at room temperature and hence they are required to be operated at high temperatures for better performance [5, 13, 17]. However, since the inflammability and explosive nature of the H 2 gas are increased with temperature, H 2 sensors are generally suggested to operate at room‐temperature [18].…”

“…However, since the inflammability and explosive nature of the H 2 gas are increased with temperature, H 2 sensors are generally suggested to operate at room‐temperature [18]. Among various metal oxides, TiO 2 is widely used for high performance room‐temperature H 2 gas detection applications [4, 5, 16].…”