adopt HEPA filter net, Two-layer photo catalyst net, UV lamp, active carbon filter net, negative ions and active oxygen. ... filter net, HEPA filter net,Two-layer photo catalyst net, UV lamp, active carbon filter net, negative ions and active oxygen2) Two ... generationof air purifier with two-layer photocatalyst to kill bacterium3) UV lamp combined with photocatalyst is not only self-sterilizing but also ...