A broadband photodetector has been developed on the basis of ZnO nanowires (NWs)/Rhodamine B (RhB) hybrid system. The device is fabricated by spraying NWs on to gold interdigital electrodes followed by modifying the NWs via an RhB solution-casting process. Measurements show that the as-fabricated device demonstrates photoresponsivity ranging from 300 nm to 700 nm with a bandwidth as large as 400 nm. The role of the dye sensitizer adsorbed on the surface of NWs is modeled to alter the transportation path of photo-generated carriers. The calculations based on the measurements reveal that the device exhibits a prominent responsivity in the interested band with maximum responsivity of 5.5 A/W for ultraviolet (UV) light and 3 A/W for visible (VIS) light under 8 V bias, respectively. The sensitization not only widens the response spectrum with external quantum efficiency leaping up to 771% at VIS but also improves UV responsivity with maximum 51% enhancement. From the time–dependent photo-current measurement, it is found that the response time (rise and decay times in total) of the device largely reduced from 17.5 s to 3.3 s after sensitization. A comparison of the obtained photodetector with other ZnO-based photodetectors is summarized from the view point of responsivity and bandwidth.

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The design of a novel eight-beam uniaxial shock accelerometer is presented. This new multi-beam structure has an advantage of high anti-disturbance capability. The designed measurement rang of the sensor is 150,000g and the sensitivity is 23.4µV/g, which is about 20 times higher than conventional sensors of same measurement rang due to the exploiting of the giant piezoresistance effect in silicon nanowires. This achievement opens up new developments in the area of shock experiments where the high overload capability and high sensitivity are both needed.

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