A Composite of Crosslinked and Quaternized Poly (4-vinylpyridine) and Polypyrrole as a Potential Candidate for the Detection of Low Humidity

1 Results Despite rapid progress in the development of resistive-type humidity sensors, the detection of low humidity is still a problem[1, 2]. In this study, poly(4-vinylpyridine) was crosslinked and quaternized with 1,4-bromobutane to form a polyelectrolyte humidity sensitive film on interdigitated gold electrodes, which was further coated with a layer of polypyrrole by a facile method of vapor phase polymerization process. The composite so prepared was characterized by UV-vis spectroscopy and scannin...

Flexible impedance sensor based on Ti_(3)C_(2)T_(x)MXene and graphitic carbon nitride nanohybrid for humidity-sensing application with ultrahigh response

This paper reported the impedance-type humidity sensor based on Ti_(3)C_(2)T_(x)/g-C_(3)N_(4)nanomaterials which was fabricated on a flexible polyethylene terephthalate(PET)substrate.The scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS)measurements were used to demonstrate the successful synthesis and combination of Ti_(3)C_(2)T_(x)and g-C_(3)N_(4)nanomaterials.The performance of the humidity sensor was tested at room temperature.The experimental results showed that the Ti_(3)C_(2)T_(x)nanosheets with g-C_(3)N_(4)nanosheets endowed the humidity sensor with an ultra-high response,rapid response/recovery time,and negligible hysteresis.The complex impedance spectroscopy(CIS)and bode diagrams were used to further analyze the sensing mechanism of the Ti_(3)C_(2)T_(x)/g-C_(3)N_(4)humidity sensor.The Ti_(3)C_(2)T_(x)/g-C_(3)N_(4)humidity sensor can monitor skin humidity and high-humidity alarm,which demonstrates great potential applications in various fields.

Experimental measurement of acoustically induced surface vibration with different soil conditions

Experimental measurement is performed to investigate the acoustically induced surface vibration with different soil conditions. Using the method of scanning detection and analyzing the three-dimensional （3D） char- acteristic diagram of surface vibration, the influence of soil properties, such as porosity and humidity, upon the signal of acoustically induced surface vibration is measured. The experimental results show that the surface vibration redu- ces with the decrease of soil porosity and reduces a little with the increase of soil humidity; and with a big plastic landmine buried, the surface vibration enhances signifi- cantly. It indicates that the signal of acoustically induced surface vibration mainly depends on soil porosity and mechanical effect of buried objects.