Molybdenum Disulphide and Titanium Dioxide Nanocomposite Based fast Humidity Sensor with Linear Response over wide Humidity Range

A humidity sensor based on MoS 2 /TiO 2 nanocomposite prepared by solid state reaction method is presented in this work. X-ray diffraction (XRD) confirms the formation of nanocomposite consisting of irregular shaped nanoparticles of different sizes (60 –200 nm). Energy Dispersive Spectroscopy (EDS) confirms the presence of Titanium, Molybdenum, Sulphur, and Oxygen in the nanocomposite. Humidity sensing characteristic of MoS 2 /TiO 2 nanocomposite are studied at room temperature from 11 to 97% relative humidity (RH) using AC impedance spectroscopy. The response and sensitivity of MoS 2 /TiO 2 nanocomposite sensor are calculated from AC impedance data. The values of response and sensitivity turn out to be 86% and ∼ 13 kΩ/ , respectively at 100 Hz. The nanocomposite sensor shows response and recovery time of ∼ 38s and ∼ 7s respectively with good repeatability. The sensor response remains stable for 30 days. Moreover, RH effect on AC conductivity and complex electric modulus of MoS 2 /TiO 2 nanocomposite are also investigated. Graphical Abstract Highlights Solid state reaction method is employed to prepare MoS 2 /TiO 2 nanocomposite. Nanoparticle of irregular size ∼ (60 –200 nm) confirmed by XRD. EDS analysis confirms the presence of Molybdenum, Titanium, Sulphur and Oxygen in nanocomposite. AC impedance spectroscopy is studies from 11 to 97% RH for characterization at room temperature. Response (86%), sensitivity (∼ 13kΩ)/%RH is achieved at 100 Hz. We found response time ∼ 38s and recovery time ∼ 7s with overall good repeatability and stability. Impact of RH on AC conductivity and complex electric modulus is explored.