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Download as PDFThe Role of Hierarchical Morphologies in the High- performance Gas Sensing of CuO-Based Chemiresistors
Gas sensors are essential in the monitoring, control, and reduction of harmful emissions in the environment [1] . Conductometric gas sensors based on semiconducting metal oxides are advantageous in many applications due to high sensitivity, manufacturability, and small size. However, there are a number of drawbacks, including difficulty in control over the semiconductor/substrate interface, high power consumption, and reduced selectivity at high temperatures (300-400˚C) required for operation [2] [3] . The development of gas sensors with innovative designs and advanced functional materials has attracted considerable scientific interest due to their great technological potential [4] . This work presents new insight towards the development of high-performance p-type semiconductor gas sensors. Gas sensor test devices, based on copper (II) oxide (CuO) with innovative and unique urchin-like structures, were prepared by a microwave-assisted synthesis method. An assembly of urchin-like structures was found to be most effective for hydrogen detection in the range of parts-per-billion (300 ppb) at low temperatures (200˚C). These results show that morphology plays an important role in the gas sensing performance of p-type semiconducting CuO gas sensors.
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- Figure 1: SEM image of urchin-like morphology.
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- Figure 2: Sensor response to hydrogen gas.
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