Figure 2.

Graphical expression of materials used in masks and their applications. There are different types of masks that can be used which rely on the basic filtration effect to trap aerosol particles during the COVID‐19 pandemic as shown by the inner circle of right wheel. Through modifying the masks with various functional materials or technologies as shown by the left wheel, it makes masks possess various functions such as antiviral and hydrophobic abilities shown in the outermost circle of the right wheel, which are significantly useful to help the world fight COVID‐19.