Improvement of Indoor Air Quality by Applying LiNbO3 on Concrete

Abstract

Photocatalysts in ordinary building materials such as concrete create environment-friendly materials by which air pollution can be diminished. In this study, LiNbO3-coated concrete block was used to investigate pollutant removal efficiency, wherein toluene and ethylbenzene were selected as common indoor air pollutants. The effectiveness of using immobilized LiNbO3 to remove ethylbenzene and toluene from indoor air was investigated under various operational parameters. About 80 % of toluene and 82.5 % of ethylbenzene could be removed within 6 h under ultraviolet-visible light illumination using LiNbO3 as a photocatalyst in concrete. Therefore, in the near future, LiNbO3 may be used as a sustainable construction material that could contribute to indoor air purification Keywords: Indoor air quality, LiNbO3, Photocatalytic degradation, Volatile organic compounds. Chemistry; Vol. 29, No. 12 (2017), 2692-2700 can also lead to the irritation of eyes and respiratory tract and to sensitization reactions involving the eyes, skin and lungs. The occurrence of these compounds in the atmosphere therefore poses a great threat to human health and the environment. Many air-purification methods are available in the literature. Existing technologies such as incineration, absorption, adsorption, and condensation ionization for controlling emissions and improving air quality are not very satisfactory because they degrade air quality [12,13]. Although filtration is the most widely used method because of its low cost and high pollutant removal effectiveness, older air filters have been associated with health issues, increased pollutant concentration and reduced work performance. Systems that are passive, cost effective and work along with existing air handling systems to reduce loading and increase overall energy efficiency are always necessary to develop [14]. One such area that has been widely explored is the use of materials that can be embedded or coated on walls and wall boards that can passively and effectively destroy indoor concentrations of pollutants [15]. Photocatalysis is a very exciting topic in the innovation of the cement industry with sustainable solutions. These innovative products have been developed to provide an environment-friendly solution in the construction industry and are becoming widely recognized for green constructions [16]. A broad utilization of white photocatalytic materials in concrete could enable the reduction of environmental pollution, thereby improving air quality. Asian Journal of