• AKASH ROY

Articles written in Bulletin of Materials Science

• ZnO–TiO2 nanocomposite: Characterization and moisture sensing studies

This paper reports morphological and relative humidity sensing behaviour of ZnO–TiO2 nanocomposite powder pellets obtained through solid-state reaction route. Resistance of the pellets is observed to decrease with increase in relative humidity in the 10–90% range. Sensing element with 15 wt%of TiO2 in ZnO shows best results with a sensitivity of 9.08 M𝛺/%RH in 10–90% relative humidity range. This sensing element manifests crystallite size of 71 nm as measured from XRD and average grain size of 207 nm calculated from SEM micrograph. This sensing element manifests low hysteresis, less effect of ageing and good reproducibility. Response and recovery times of this sensing element are measured to be 84 s and 396 s, respectively.

• Electrical and optical properties of ZnO–WO$_3$ nanocomposite and its application as a solid-state humidity sensor

This study reports the humidity sensing characteristics of ZnO–WO$_3$ nanocomposite. Pellet samples of 0–5 weight% ZnO in WO$_3$ were sintered from 300 to 600$^{\circ}$C. When exposed to humidity, the resistance of the sensing samples was found to decrease with increase in relative humidity (RH). Five percent ZnO-doped WO$_3$ showed maximum sensitivity of 20.95 M$\Omega$/%RH in 15–95% RH range. Sensor parameters like reproducibility, aging, hysteresis, response and recovery times were also studied. Sensing mechanism is discussed in terms of sintering temperature, composition and crystallite size of the sensing element. It was observed that sensing mechanism is strongly based on annealing temperature and percentage of doping. The sensing samples have also been investigated by X-ray diffraction, scanning electron microscope (SEM) and Raman spectroscopy. The crystalline size of the sample was identified by powder X-Ray Diffraction data. The SEM analysis was used to study the surface morphology. The structure, phase and the degree of crystallinity of the materials were examined by Raman spectroscopy.

• # Bulletin of Materials Science

Volume 44, 2021
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020

Physical Sciences 2020

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019