Highly Porous-Cellulose-Acetate-Nanofiber Filters Fabricated by Nonsolvent-Induced Phase Separation during...

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Engineering

Background:

• Particulate matter (PM2.5) poses significant health risks.
• Efficient and cost-effective filtration materials are needed for PM2.5 capture.
• Cellulose acetate (CA) is a versatile polymer for fabricating nanofibers.

Purpose of the Study:

• To develop highly porous cellulose acetate (CA) nanofibers using electrospinning and nonsolvent-induced phase separation (NIPS).
• To optimize the solvent system and CA concentration for enhanced porosity and specific surface area.
• To evaluate the PM2.5 capture efficiency of the fabricated porous CA nanofibers.

Main Methods:

• Electrospinning of cellulose acetate (CA) using a nonsolvent-induced phase separation (NIPS) mechanism.
• Selection of good solvents (e.g., N,N-dimethylacetamide) and poor solvents (e.g., dichloromethane, tetrahydrofuran, acetone) based on Hansen solubility parameters.
• Characterization of porous CA nanofibers using techniques to determine specific surface area and pore structure.
• Evaluation of PM2.5 capture efficiency using optimized nanofiber filters.

Main Results:

• Porous CA nanofibers were successfully prepared using binary solvent systems (DCM:DMAc and THF:DMAc).
• The highest specific surface area (1839 m²/g) was achieved with a DCM:DMAc ratio of 1:9.
• Porous structure was confirmed from the surface to the core of the nanofibers.
• A PM2.5 capture efficiency of 98.2% was achieved using porous CA nanofibers from a 10 wt.% CA solution.

Conclusions:

• A novel strategy using NIPS electrospinning effectively produced highly porous CA nanofibers.
• Optimized porous CA nanofibers demonstrate excellent potential for high-efficiency PM2.5 air filtration.
• This method offers a promising approach for developing advanced filtration materials for environmental applications.