Vanadium oxide thin films were grown on both quartz and Si(111) substrates utilizing pulsed RF magnetron sputtering technique at room temperature with RF power at 100 W to 700 W. The corresponding thicknesses of the films were increased from 27.5 nm to 243 nm and 21 nm to 211 nm as RF power increased from 100 W to 700 W for quartz and silicon substrates, respectively. X-ray diffraction and field emission scanning electron microscopy were carried out to investigate the phase and surface morphology of the deposited films. Electronic structure and vanadium oxidation states of the deposited films were investigated thoroughly by X-ray photoelectron spectroscopy. As-grown films show stoichiometric vanadium oxide only where vanadium is in V 5+ and V 4+ states. Phase transition of vanadium oxide films were investigated by differential scanning calorimetric technique. The reversible i.e. smart transition was observed in the region from 337 °C to 343 °C. Average hemispherical emittance of the deposited vanadium oxide films was evaluated by an emissometer in the wavelength range of 3 µm to 30 µm. The sheet resistance of the deposited films was measured by two-probe method and data were in the range of 10 6 to 10 5 Ω/square. Optical properties of the films such as solar transmittance, solar reflectance and solar absorptance as well as optical constants e.g. optical band gap were also evaluated. Finally, mechanical properties such as nanohardness and Young's modulus at microstructural length scale were evaluated employing nanoindentation technique with continuous stiffness mode.

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The present pandemic coronavirus disease 2019 (COVID-19) becomes a serious concern of global health threat which is elicited by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This paper focuses on a hitherto untouched material's engineering issue in human scientific fight against the well-known COVID-19. We show here the challenges and possibilities in engineering the surface to fight against survivability of SARS-CoV-2 that has caused a global pandemic. It is a fact that this virus causes severe acute respiratory syndrome and hence is nicknamed as e.g. SARS-CoV-2. In this perspective; the present work provides a critical survey about the severity of indirect contact mode transmission and survivability of various coronavirus families on different material surfaces. Furthermore, the possible direction for future research needed to develop antiviral material surfaces that can be regularly used to tackle such pandemic outbreaks is identified. Finally, the missing link between the biologist's approach and the material scientist's approach in tackling such pandemics is discussed along with scopes and challenges in future interdisciplinary research.