High-sensitivity and fast-response humidity sensor (Shinshu University Faculty of Engineering)

It is a capacitive humidity sensor that is 100 times faster than conventional commercial products!

This is a capacitive humidity sensor that combines polyimide, which has excellent heat resistance and chemical stability, with MWCNT (multi-walled carbon nanotubes) and SWCNT (single-walled carbon nanotubes), achieving a response time on the order of 10 ms, which is 100 times faster than conventional sensors. Carbon nanotubes (CNT) have a nanoscale mesh structure, making them gas-permeable electrodes. It is also important that the upper electrode does not hinder the movement of gas molecules; for example, in the case of a humidity sensor that permeates water vapor, high hydrophobicity can be expected to enable a fast response. This technology improves response speed, sensitivity, temperature change suppression, and durability compared to conventional humidity sensors by attaching CNT as the upper electrode to a thin film of polyimide, whose electrical properties change due to water vapor or gaseous chemicals.

Thermo-hygrometer