Computational studies on binary transition metal oxide surfaces for environmental remediation

Abstract

Anthropogenic environmental pollution causes adverse effects on the earth and human beings. The emission of pollutants to the environment by manmade resources is known as anthropogenic emission. The emission of toxic gases such as NOx, CO2, SO2, and methane from the industry and automobile wastes such as petrol and diesel engines are causing major atmospheric air pollution. The concentration of the air pollutant is constantly increasing due to industrial revaluation. The greenhouse effect, global warming, the destruction of ozone layers, acid rain, and the changes in the environmental nitrogen cycle are the impacts of atmospheric air pollution on the Earth. For human beings, it affects the respiratory system, increases lung inflammation, and causes breathing difficulties. In addition to that, the harmful NOx pollutant may cause severe damage to the lungs by infiltrating into it, and leads to the emergence of bronchitis, emphysema, and exacerbates heart diseases. Nitrogen oxide (NOx) is considered a major anthropogenic air pollutant among the various atmospheric air pollutants. The Nitrogen Oxide (NOx) family contains Nitrogen Monoxide (NO), Nitrogen dioxide (NO2), and Nitrous Oxide (N2O). newlineThe NOx pollution-controlling mechanism is two-prolonged: (1) preventing the formation of NOx by utilizing combustion control techniques. (2) reducing the existing NOx by selective catalytic and non-catalytic reduction. Reducing the harmful NOx from the atmosphere through a photo-catalytic process is considered the most promising approach. newlineTransition metal oxides such as TiO2, ZnO, SnO2, V2O5, WO3, Nb2O5, and MnO2, are widely studied for their photocatalytic property towards pollution reduction. Among these, TiO2 is considered the most promising semiconductor photocatalyst, for its superior physicochemical properties. TiO2 is non-toxic, chemically inert, thermally stable, photo-stable, and relatively cheap. Naturally occurring TiO2 exhibits three kinds of polymorphism namely, Anatase, Rutile, and Brookite.