Two dimensional Zirconium diselenide based humidity sensor for flexible electronics

Transition metal dichalcogenides (TMDCs), a class of two-dimensional (2D) materials with layered structures, have recently gained a lot of attention for highly sensitive humidity sensing applications. Hence, for the first time, it proposes a highly sensitive and fast humidity sensor based on the 2D Zirconium Diselenide (ZrSe₂) material with unique humidity sensing performance via printed technologies. The spin coating technique was used to deposit the 2D ZrSe₂ flakes onto the inter-digital electrodes (IDEs). Herein, the bulk ZrSe₂ powder was exfoliated into the 2D flakes via wet grinding. The proposed sensor shows a high sensitivity of 68 kΩ / %RH (where RH is relative humidity) with a wide detection range of (15–80%) RH having good linearity and stability over 360 min. The sensor showed a transient response of 1 s and 2 s for impedance while 3 s and 6 s for capacitance. Hence, the fabricated sensor can be exhibited an ultra-high sensitivity and quick response in various applications: contactless humidity sensing, water spraying test, and skin humidity test. From these exceptional performances, the proposed sensor can be applied in multiple humidity sensing applications.