TABLE 2.
Some basic details of electrospinning process and outcomes
| Filtration materials | Application | Working parameters | Results | Ref. |
|---|---|---|---|---|
| Cellulose acetate and PP non‐woven | Fabricate multilayered filtration material | Needle diameter: 0.7 mm, f = 0.3 ml/h, d = 10 cm, and V = 25 kV. | The layer of nanofibres electrospun onto PP nonwoven material increased the η f of PP nonwoven material from 50.23% to 91.29%, however, the Q f reduced by 29.1%. When the cellulose acetate deposition time was increased from 3 to 6 h, the η f further increased to 98.26% and the Q f was relatively increased by 0.6%. The mean pore size was 0.463 and 15.640 mm for CA nanofibres and PP nonwoven material, respectively. | Omollo et al.121 |
| (PVA)/cellulose nanocrystals (CNCs) | Fiber‐based filters for indoor air purification | A 5 ml syringe with a 22‐G needle, d = 10 cm and V = 22 kV. | The thinner fibers reduced pressure drop significantly and enhanced the efficiency of particulate matter removal. 99.1% of η f was achieved in extremely polluted conditions (the mass concentration of particle diameters ≤2.5 μm is 500 μg m−3) with low pressure drop (91 Pa) at an airflow velocity of 0.2 m s−1. | Zhang et al.128 |
| Chitosan / PEO | ‐ | f = 0.08 ml/min, d = 10 cm, and V = 30 kV | Increasing the fiber diameter, the η f decreased because the maximum pore size and air permeability increased. With increasing fiber diameter, the polystyrene bead η f decreased. This is likely due to higher maximum pore size observed with increasing fiber diameter along with increase in air permeability. | Desai et al.125 |
| Chitosan Nanoparticle/PLA | Air filtration and antibacterial performance | A 5 ml syringe with a 21‐G needle tip, f = 1 ml/h, d = 14 cm, and V = 18 kV. | Compared to the pure PLA membrane (99.90%), the η f of PLA/chitosan fibrous membranes was slightly lower at 98.10%–98.99%, whereas the chitosan content had almost no effect on the η f. However, the pressure drop of pure PLA membrane was 335.90 Pa and it decreased to 167.05 Pa when the mass ratio of chitosan to PLA was 1:8. When the mass ratio of chitosan to PLA was 2.5:8, the Q f (up to 0.0312) was the highest, which indicated the best filtration performance. | Li et al.65 |
| Silk protein nanofibres/PEO | Multifunctional air filters | The 21 G nozzle tip, d = 20 cm, f = 10 μL/min and V = 10 kV | Air ηf of the fabricated SNAFs could reach up to 90% and 97% for PMs with sizes under 2.5 and 10 μm, respectively, exceeding the performances of commercial semi‐high‐efficiency particulate air (semi‐HEPA) filters. After use, the SNAFs could be naturally degraded. | Min et al.129 |
| Gelatin/β–cyclodextrin Bio–nanofibres | Respiratory filter media | The 23 G nozzle tip, f = 0.15 ml/h, d = 20 cm, and V = 22 kV | Gelatin/β‐cyclodextrin nanofibres captured aerosols (0.3–5 μm) with ˃95% η f at 0.029/Pa Q f. They adsorbed significant amount of xylene (287 mg/g), benzene (242 mg/g), and formaldehyde (0.75 mg/g) volatile organic compounds. | Kadam et al.130 |
| Ag doped keratin/PA6 nanofibre | Air filtration and antimicrobial performance | A 15 ml syringe with a 20 G flat‐tip needle, f = 0.1 ml/h, d = 25 cm, and V = 20 kV | The addition of the Ag nanoparticles (AgNPs) imparted a strong antibacterial activity to the composite membrane against S. aureus (99.62%) and E. coli (99.10%). Bacterial η f of the composite membrane against S. aureus and E. coli were up to 96.8% and 95.6%, respectively. The usage of coarse wool in bio‐protective air filters could offer tremendous economic benefits to enterprises. | Shen et al.109 |
| Keratin (K) –polysulfone (PS) blend | Wastewater treatment applications | A 5 ml syringe with a 22 G needle, f = 0.8 ml/h, d = 12 cm, and V = 12 kV. | The performance of PS‐K membranes in tannery effluent treatment resulted in 76% enhanced dye removal efficiency. | Karunanidhi et al.131 |
Abbreviations: d, tip to collector distance; f, feed rate; Q f, quality factor; η f, filtration efficiency; SNAF, silk nanofibrous air filters; G, gauge.