Integration of SnO2 Nanoparticles with Micro-hotplatform for Low-power-consumption Gas Sensors

Abstract

A gas sensor with low power consumption was manufactured using a suspended microhotplatform (MHP) fabricated by MEMS technology. Tin oxide nanoparticles, synthesized by the hydrothermal method, were deposited on the MHP by dip coating in the form of slurry. The obtained SEM images indicated that nanoparticles were well connected and uniform in size. The gas sensing performance was also investigated in both dynamic and static test systems. In the dynamic test system, the response (R air /R gas) of the sensor exhibited a representative linear relationship with hydrogen at a power of 14.42 mW and changed from 1.17 to 4.51 at 5 to 100 ppm hydrogen. In the static test system, the sensor demonstrated an obvious response to ethanol, ammonia, and glycol; the response to the target gas of ammonia at a concentration of 120 ppm reached up to 23.94. The power consumption of the sensor was only 16 mW with a platinum (Pt) heating resistor at 255 ℃.

Low-Concentration Ammonia Gas Sensors Manufactured Using the CMOS–MEMS Technique

“…The sensing film was PPy/RGO, which was synthesized using the oxidation-reduction method. Most ammonia gas sensors use a micro-heater [9][10][11][12][13] to generate an appropriate WT of 225-330 • C for the sensing film, so the power consumption is quite high. This study details the production of an AGS without a micro-heater, which operates at room temperature, so it is very efficient in terms of power consumption.…”

“…Table 1 lists the process method, sensing material, and working temperature of various ammonia gas sensors. Peng [9] used the MEMS process to produce an ammonia gas sensor (AGS) with a micro-hotplate that consumed less power. The AGS used nanoparticulate tin dioxide as the gas sensing material, which was prepared using the hydrothermal method.…”

“…The oxidation-reduction method is used to synthesize the sensing film, which consists of PPy/RGO. Most gas sensors [6][7][8][9][10][11][12] have a heater to generate the WT for the sensitive film, but this study produced an AGS without a micro-heater. This AGS operates at room temperature, so it is more efficient in terms of power consumption.…”

Development of an Approach to Increase Hydrogen Measurement Selectivity

“…Available hydrogen leak detectors can be classified according to the type of transducer they use. The main transducers used in instruments for gas analysis include electrochemical, (4) semiconductor, (5) and catalytic sensors. (6,7) Each type of sensor has its own advantages and disadvantages, which determine their fields of application.…”