There is a growing concern about the impact of air quality on human health. The industrialization based on the large use of fossil fuels has led to increased production of harmful air pollutants, such as volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen and sulfur oxides (NO _x , SO _x ), pathogens, and particulate materials. Looking at cost-effective ways to eliminate such pollutants, nanostructured materials that can act as photocatalysts for air purification are one of the potential energy-efficient methods for pollution control, adding new functionalities to traditional building materials. In this chapter, an overview of the recent development of air purification photocatalytic systems based on nanostructured metal oxide semiconductors, carbon-based materials, and heterostructures is provided as well as state-of-art material design strategies aimed at improving their performances.