Synthesizing Metal Oxide Semiconductors on Doped Si/SiO(2) Flexible Fiber Substrates for Wearable Gas Sensing

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.