Hong Hoang Si, Hoang Tran Vinh
School of Electrical Engineering, Hanoi University of Science and Technology, Hanoi, 100000, Vietnam.
School of Chemical Engineering, Hanoi University of Science and Technology, Hanoi, 100000, Vietnam.
J Nanosci Nanotechnol. 2021 Apr 1;21(4):2495-2499. doi: 10.1166/jnn.2021.19118.
We developed a novel sensor structure by synthesizing Pd nanocubes (NCs) decorated on ZnO nanostructures (NSs) applied to resistive-type H₂ gas sensor with micro-length in sensing channel. The ZnO NSs were selectively grown between micro-size finger-like interdigital electrodes through microelectromechanical technology. The novel H₂ sensor structure with the sensing channel was reduced to micro-size by this proposed method to obtain a sensor with fast response/recovery time. The as-prepared structure exhibited robust sensing performance with a response of 11% at optimal temperature of 150 °C, good linearity, and fast response/recovery time within 10 s. The speed of chemisorption through the diffusion pathway in Pd NCs combined with micro-length in sensing channel in sensor showed fast response and recovery times of 9 and 15 s, respectively, toward 10,000 ppm (1%) H₂ at 150 °C. The result showed approximate linearity response in H₂ concentration range of 5÷10,000 ppm and a large operating temperature range from room temperature to 200 °C.
