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. Graphical abstract