Fabrication and Analysis of Energy Efficient Low-Cost Wireless Gas Sensor Based on ZnO Thin Films.

Industrialization can be greatly appreciated only by limiting the downside of the proposed technology. In this aeon, the recurrent monitoring of industries is statutory in detecting harmful gases and explosions for the global environment safety. Hence, employing specific gas sensors for detecting malicious gases benefits the welfare of the society. Thus, in this present work, we developed an energy efficient toxic gas sensor using ZnO thin film by seed layer assisted hydrothermal technique. The sensing mechanism of ZnO with the CO analyte was explained and the sensing parameters such as sensitivity, selectivity, response and recovery time were studied. Further, the developed energy efficient sensor was embedded with wireless sensor assembly for online monitoring which may be functional in developing portable, compact and cost-effective system for various real time industrial control applications.

Investigation on CH4 sensing characteristics of hierarchical V2O5 nanoflowers operated at relatively low temperature using chemiresistive approach.

Methane (CH4) gas, the second most potent greenhouse gas share a substantial role in contributing to the global warming and it is a necessary pre-requisite to detect the release of CH4 into the environment at its early stage to combat climate change. In that front, this work is focussed to develop an effective CH4 gas sensor using vanadium pentoxide (V2O5) thin films that works at an operating temperature of ∼100 °C. To understand the effect of sputtering power towards the structural characteristics of V2O5 films, X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) analysis were performed from which the orthorhombic polycrystalline structure of V2O5 thin films was confirmed with varied texture co-efficient. Further, the surface elemental studies using X-ray photoelectron spectroscopy (XPS) confirmed the prominence of V+5 oxidation state from the binding energy of V2p3/2 and O1s peak. The effect of sputtering power on the growth of different nanostructures were observed using field-emission scanning electron microscopy (FE-SEM). The critical role of adsorption and desorption kinetics of the deposited nanostructures were explained through first order kinetics based on Elovich model and the phase stability of different nanostructures were evaluated using Raman spectral analysis. This work achieved the sensor response of about ∼8% towards CH4 at an operating temperature of 100 °C towards 50 ppm concentration.