Synthesizing Metal Oxide Semiconductors on Doped Si/SiO <sub>2</sub> Flexible Fiber Substrates for Wearable Gas Sensing
Feng Niu, Fugong Zhou, Zhixun Wang, Lei Wei, Jie Hu, Lei Dong, Yifei Ma, Mei Wang, Suotang Jia, Xuyuan Chen, Zhaomin Tong
Abstract
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/SiO 2 flexible fibers by a thermal drawing method as substrates to fabricate MOS gas sensors. A methane (CH 4 ) 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 SiO 2 cladding was an insulating substrate. The gas sensor was integrated into a miner cloth as a wearable device, and the concentration change of CH 4 was monitored in real time through different colored light-emitting diodes. Our study demonstrated the feasibility of using doped Si/SiO 2 fibers as the substrates to fabricate wearable MOS gas sensors, where the sensors have substantial advantages over tradition sensors in flexibility, heat utilization, etc.