Electrospinning Equipment for Research| Sustainable nanocellulose-basedelectrospinning: Unlocking advancedmaterials for future technologies

National University of Singapore's Academician Seeram Ramakrishna & Nanjing Forestry University's Associate Professor Yu Juan: Recent Advances in Nanocellulose-Based Electrospun Nanofibers

Electrospinning technology, as a crucial method for producing micro/nanofibers, demonstrates tremendous potential in energy, biomedical, and other fields. However, its industrialization still faces numerous challenges. Firstly, traditional electrospinning materials primarily rely on petroleum-based polymers, which are not only unsustainable in raw materials but also create significant environmental burdens through waste. Secondly, existing electrospun fibers commonly suffer from insufficient mechanical strength and limited functionality, restricting their applications in high-end fields.To overcome these limitations, researchers are actively exploring bio-based reinforcement materials. Among these, nanocellulose (NC) is regarded as the most promising reinforcement option due to its exceptional mechanical properties (theoretical modulus up to 150 GPa), tunable surface chemistry, and completely renewable characteristics. Nevertheless, key scientific challenges remain in effectively integrating NC into electrospinning systems: resolving the contradiction between NC's dispersibility and interfacial compatibility in polymer matrices, and achieving the unification of performance and sustainability in large-scale production.

Recently, Academician Seeram Ramakrishna from the National University of Singapore and Associate Professor Yu Juan's team from Nanjing Forestry University published their latest research titled "Sustainable nanocellulose-based electrospinning: Unlocking advanced materials for future technologies" in the journal *Materials Today*. The study systematically reviews recent advances in NC-based electrospun nanofibers, with particular focus on the mechanisms by which size effects and surface modifications influence fiber morphology, interfacial interactions, and functional properties.Research shows that through strategies such as premixing, post-coating, and Pickering emulsions, NC can effectively enhance the performance of polymer-based composites, providing sustainable solutions for applications including drug delivery, wearable electronics, water treatment, and food packaging. These breakthrough advancements have positioned NC-based electrospun fibers as a key platform driving the development of next-generation multifunctional materials, opening new pathways for innovation in materials science.

Figure 1: Integration strategies of nanocellulose with electrospinning technology and their applications across various fields

The preparation of nanocellulose-reinforced electrospun nanofibers primarily employs two strategies:

1) **Premixing method**: NC is dispersed in spinning precursor solutions through solvent exchange, chemical modification, or Pickering emulsions, which can significantly improve fiber mechanical properties and thermal stability, but requires solutions to NC-polymer interfacial compatibility issues.

2) **Post-coating method**: NC is deposited on formed fiber surfaces through spraying or dipping to construct functional coatings. This approach effectively improves fiber hydrophilicity, mechanical strength, and functional characteristics without altering the spinning process.

Each method has distinct advantages: premixing achieves uniform NC dispersion within fibers, while post-coating more easily introduces multifunctional composite coatings.

Figure 2: Preparation strategies for nanocellulose-based electrospun nanofibers

As a green reinforcement, nanocellulose can significantly improve the microstructure of electrospun fibers. Its high specific surface area and rod-like structure can induce polymer nucleation, refine fiber diameter, and promote molecular chain orientation crystallization. In terms of physical properties, NC incorporation simultaneously enhances the mechanical strength and thermal stability of composite fibers, though excessive addition (>12 wt%) may cause agglomeration effects.

Through chemical modifications (such as PCL grafting or pH-responsive modifications), NC can endow electrospun fibers with enhanced interfacial compatibility (improved elongation at break) and smart responsive properties, though current modification methods remain limited by the use of organic solvents.

Figure 3: Effects of nanocellulose addition on performance of electrospun composite fibers

NC incorporation has significantly improved the piezoelectric performance of electrospun fibers. Its interfacial polarization effect effectively enhances the piezoelectric charge constant of composites and increases power output. NC's high specific surface area and abundant hydroxyl groups provide active sites for sensing materials. Further chemical modifications (e.g., sulfonation) can enhance the responsive performance of NC-based electrospun fibers. Sulfonated CNC/PHB nanogenerators demonstrate 5 times higher output voltage than conventional materials while maintaining stability after 15,000 cycles.

Figure 4: Applications of nanocellulose-based electrospun fibers in electronic sensors

Paper link: https://doi.org/10.1016/j.mattod.2025.04.006