Fabrication of Multifunctional Filters via Online Incorporating Nano‐TiO₂ into Spun‐Bonded/Melt‐Blown Nonwovens for Air Filtration and Toluene Degradation

Abstract

Multifunctional air filters with high filtration efficiency for aerosol and good degradation for toluene and bacteria are fabricated via online incorporation of TiO2/Ag nanoparticles into the composite nonwovens with spun‐bonded/melt‐blown (SM) hierarchical structure. Today, severe environmental pollution attributed to atmospheric pollutants, mainly including particulate materials, and gaseous volatile organic compounds, as well as bacterial and viral contaminants, has drawn worldwide attention. In this work, a novel online incorporation technique to fabricate a multifunctional air filter with hierarchical structure of SM nonwovens and TiO2 based nanoparticles is proposed. The in situ incorporation technique not only enables the SM nonwovens filters with four orders increment on toluene degradation rate, but also increases filtration quality factor Qf of the SM filters to 0.2251 Pa−1. This research shows promising applications of the multifunctional TiO2/SM nonwoven filters for indoor air remediation. In addition, this scale‐up fabrication method of fiber‐based filters will potentially promote engineering of macromolecular fiber materials.

Review on Polymeric, Inorganic, and Composite Materials for Air Filters: From Processing to Properties

“…This was achieved by online powder spraying of the particles onto the freshly generated fibers and subsequent thermal conjunction with spunbond layer into a hierarchically structured composite, as shown in Figure 5. [95] The addition of nucleating agents such as magnesium stearate (MgSt) particles to the matrix polymer could enhance the filter charge by improving the crystal structure. Subsequent corona charging, which was carried out by applying high potentials on the material, upon discharge resulted in the deposition of ions in the electret material.…”

“…[220] Incorporation of the well-known TiO 2 photocatalyst into silver and PP composite air filter could achieve an effective degradation of 93.4% of toluene under irradiation with UV light. [95] In the process, degradation is ensured by oxidation of the pollutant by free hydroxyl radicals on the TiO 2 surface. Similarly, Ag@CNTs composite with a high surface area was applied to effectively catalyze the oxidation and degradation of formaldehyde under UV light.…”

An Advanced Dual‐Function MnO2‐Fabric Air Filter Combining Catalytic Oxidation of Formaldehyde and High‐Efficiency Fine Particulate Matter Removal

“…Among fibrous filter materials, PP melt‐blown nonwovens provide excellent filtration owing to the high surface area per unit weight, high insulation value, high barrier properties, and ease of large‐scale production. [ 29,30 ] As shown here, the functionality of PP filters can be extended to play a pivotal role as nanoparticle catalyst supports for air purification systems.…”

The Effect of Temperature and Humidity on the Filtration Performance of Electret Melt-Blown Nonwovens

“…The upstream and downstream photometers are used to measure the aerosol quantities on both of the upstream and downstream sides of the filters. Then the filtration efficiency can be calculated as follows in Equation (1) [20,21].…”