Do you know how air purifiers work (2)?

Active purification principle (no filter type):

The fundamental difference between the principle of active air purifier and the principle of passive air purification is that active air purifier gets rid of the restrictions of fans and filters, instead of passively waiting for indoor air to be drawn into the purifier for filtration and purification. Instead, it effectively and actively releases purification and sterilization factors into the air, and through the characteristics of air diffusion, it reaches all corners of the room to purify the air without dead ends.
The technologies for purifying and sterilizing factors on the market mainly include silver ion technology, negative ion technology, low temperature plasma technology, photocatalyst technology and plasmonic ion technology, etc. The biggest defect of such products is the problem of excessive ozone release.

Double purification type (active purification + passive purification):

This purifier is actually a combination of passive purification technology and active purification technology.