High-Throughput Electrospinning System| Silk Nanofbrillar Aerogel as Sustainable Filters forEnvironmental Purifcation

Professor You Renchuan (Wuhan Textile University): Silk Nanofibers for Sustainable Filtration Materials

Environmental pollution threatens human health and ecosystem sustainability, driving massive demand for filtration materials. However, petroleum-based filters are equally harmful as they resist landfill degradation, generating vast waste. While biodegradable synthetic polymers have been considered as alternatives, creating ultrafine fibers for 3D filtration remains challenging.

Recently, Professor You Renchuan’s team at Wuhan Textile University published research in Small titled "Silk Nanofibrillar Aerogel as Sustainable Filters for Environmental Purification." The team developed fully biomass-derived, biodegradable silk nanofiber (SNF) aerogels for multifunctional filtration. Solvent-mediated ice crystal growth enabled scalable production of structurally tunable aerogels for water/air purification. Adding minimal chitosan enhanced mechanical strength and water resistance.

Figure 1: Design, preparation, and morphology of silk nanofiber aerogels.

Figure 2: Structural regulation of silk nanofiber aerogels.

By adding a small amount of chitosan, SNF-based aerogels can obtain enhanced mechanical properties and good water resistance. SNF-based aerogels exhibit excellent biocompatibility and superior water purification performance, efficiently removing organic dyes, heavy metal ions, and micro/nanoplastics ranging from 20 nm to 3 μm in size. The practical applicability of the SNF-based aerogel system was demonstrated through simulated wastewater and river water purification experiments.

Figure 3: Assembly of silk nanofiber aerogel filters and their filtration performance for micro/nanoplastics.

Figure 4: Filtration performance of silk nanofiber aerogels for metal ions and dyes, and demonstration of wastewater purification capability.

Additionally, SNF aerogels demonstrate outstanding air filtration performance, capable of efficiently filtering PM0.3 and smoke to achieve air purification. 

Figure 5: Air purification performance of silk nanofiber aerogels.

 Furthermore, SNF aerogel filtration materials have minimal environmental impact and can safely biodegrade in natural environments. Commercial PP melt-blown fabrics show almost no degradation after one year in landfills, while SNF-based aerogel waste can completely degrade without composting treatment, achieving a degradation rate of over 70% after one year in landfills. 

Figure 6: Natural landfill degradation capability of silk nanofiber aerogels.

 This work provides an effective approach for developing biodegradable nanofiber filtration materials.