Synthesizing metal oxide semiconductors on doped Si/SiO₂ flexible fiber substrates for wearable gas sensing

• Main Authors: Niu, Feng, Zhou, Fugong, Wang, Zhixun, Wei, Lei, Hu, Jie, Dong, Lei, Ma, Yifei, Wang, Mei, Jia, Suotang, Chen, Xuyuan, Tong, Zhaomin
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Electrical and electronic engineering; Flexible Fibers; Gas Sensing
• Online Access: https://hdl.handle.net/10356/169246
• Institution: Nanyang Technological University

Traditional metal oxide semiconductor (MOS) gas sensors have limited applications in wearable devices owing to their inflexibility and high-power consumption by substantial heat loss. To overcome these limitations, we prepared doped Si/SiO2 flexible fibers by a thermal drawing method as substrates to fabricate MOS gas sensors. A methane (CH4) gas sensor was demonstrated by subsequently in situ synthesizing Co-doped ZnO nanorods on the fiber surface. The doped Si core acted as the heating source through Joule heating, which conducted heat to the sensing material with reduced heat loss; the SiO2 cladding was an insulating substrate. The gas sensor was integrated into a miner cloth as a wearable device, and the concentration change of CH4 was monitored in real time through different colored light-emitting diodes. Our study demonstrated the feasibility of using doped Si/SiO2 fibers as the substrates to fabricate wearable MOS gas sensors, where the sensors have substantial advantages over tradition sensors in flexibility, heat utilization, etc.