A filter media can include a fiber coated with a barrier coating that is substantially non-reactive to reactive species, and a photocatalytic coating disposed on the barrier coating, wherein the photocatalytic coating generates reactive species in response to illumination with optical radiation.

A filter may remove PM.sub.2.5 and/or other airborne pollutants, which filter has fibers of an average diameter of no more than 500 nm, the fibers of at least 90 wt. % polyacrylonitrile, relative to all fibers in the filter; and a catalyst of at least 90 wt. % TiO.sub.2, relative to all catalytic metals in the filter, dispersed onto the fibers. The fibers need not be charged. The TiO.sub.2 may be condensed or precipitated onto the fibers out of a liquid containing the TiO.sub.2 and the fibers by simple methods. The catalyst may be activated by UV irradiation to decompose particulate matter having an average particle size of 2.5 μm or less, i.e., PM.sub.2.5, and/or other airborne pollutants from air. Such filters may be implemented around areas of vehicle traffic, e.g., as elements of traffic lights, and may be used to controllably purify polluted air.

The present disclosure relates to an air purification filter including a substrate, and an enzyme and glycine supported on the substrate, wherein the enzyme includes at least one enzyme selected from the group consisting of β-1,3-glucanase, chitinase, lysozyme, protease, glycosidase, β-galactosidase, endo-β-N-acetylglucosaminidase and endolysine.

Processes for increasing the viricidal activity of a fiber substrate. The fiber substrate is provided. An antiviral treatment containing a quaternary ammonium or phosphonium compound is introduced to the fiber substrate to form an antiviral substrate. The treated fiber substrate is washed and dried. The antiviral treatment may occur before or after the fiber substrate is incorporated into the HEPA filter media in a papermaking process. Also a filter made from treated fiber substrates.

A nonwoven fabric including a first layer made of spunbond fibers and a second layer made of meltblown fibers, wherein the first layer is bonded with the second layer, and wherein the spunbond fibers of the first layer are interspersed with the meltblown fibers of the second layer so that the nonwoven fabric exhibits enhanced breathability and filtration properties. In exemplary embodiments, the nonwoven fabric may be used in personal protective equipment, such as, for example, face masks and respirators.

Provided is filtration member for use in a filtration device, said filtration member comprising a layer of woven or nonwoven fabric having two primary surfaces and a layer of chemically functionalized graphite flakes deposited on at least one of the two primary surfaces or embedded in the layer of woven or nonwoven fabric, wherein said graphite flakes comprise chemical function contain 1%-50% by weight of a non-carbon element selected from O, N, H, F, Cl, Br, I, or a combination thereof. Also provided is a face mask comprising: (a) a mask body configured to cover at least wearer's mouth and nose; and (b) a fastener to hold the mask in place on the wearer's face; wherein the mask body includes (i) an air-permeable outer layer, (ii) an inner layer located on a wearer's side when the mask is worn, and (iii) the filtration member comprising graphite flakes.

The disclosure provides a composite protective material for epidemic prevention of corona virus disease 2019 (COVID-19) and a preparation method thereof. The composite protective material for epidemic prevention of COVID-19 comprises a support layer, a nanofiber antibacterial layer and a skin friendly layer which are successively arranged from outside to inside, wherein the nanofiber antibacterial layer comprises at least one layer of hydroxyl terminated hyperbranched polyester nanofiber non-woven fabric loaded with graphene modified by diisocyanate and at least one layer of carboxyl terminated hyperbranched polyester nanofiber non-woven fabric loaded with graphene modified by polyethylene polyamine, wherein the hydroxyl terminated hyperbranched polyester nanofiber non-woven fabric and the carboxyl terminated hyperbranched polyester nanofiber non-woven fabric are condensed and crosslinked to form a penetrating network; the graphene modified by diisocyanate and the terminal hydroxyl of the hydroxyl terminated hyperbranched polyester nanofiber or amino of polyethylene polyamine form chemical bonding, the amino of polyethylene polyamine and the terminal carboxyl of the carboxyl terminated hyperbranched polyester nanofiber or isocyanate of diisocyanate form chemical bonding, thereby endowing dacron fabrics with excellent antibacterial property, chemical property and air permeability.

A filter which includes a layer of non-woven material infused with or containing particles of pharmaceutical salt and optionally essential oil for use in a face mask, is provided. The particles can be infused by a halogenerator. The filter can be placed in a pocket on an exterior side of a facial section, or otherwise attached to the facial section of the face mask. The salt filter deactivates the virus or other pathogen and thus effectively limits the transmission of viruses and other pathogens to and from a person wearing the face mask. The facial section can be formed of a mesh material. The face mask, including the salt filter, is preferably breathable, and light-weight, reusable.

An entrainment-based filtering system for use in connection with a facemask or respirator that includes: a filter housing defining an interior volume comprising at least one airflow pathway having an airflow pathway length that is longer than the length of the interior volume and spaced within the interior volume; and a plurality of entrainment substrates. The plurality of entrainment substrates is positioned within the at least one airflow pathway and the plurality of substrates and the dimensions of the at least one airflow pathway together function to entrain particles on the surface of the chemically coated entrainment substrates and prevent at least 95% of particles traveling through the at least one airflow pathway from exiting the entrainment-based filter.

Disclosed are improved polymer materials. Also disclosed are fine fiber materials that can be made from the improved polymeric materials in the form of microfiber and nanofiber structures. The microfiber and nanofiber structures can be used in a variety of useful applications including the formation of filter materials.