Large-Scale Nanofiber Manufacturing| Innovations Progress in Emerging Multifunctional Aramid Nanofiber Aerogels

Background:
Shaanxi University of Science & Technology Zhang Meiyun & Yang Bin Team ACS AMI "Functional Aerogels" Invited Review: Innovative Progress in Emerging Multifunctional ANF Aerogels

Aerogels have attracted widespread attention from academia and industry due to their low density, high porosity, and large specific surface area. As ideal nanobuilding blocks for aerogels, aramid nanofibers (ANFs) have generated great research interest for frontier applications. Prof. Zhang Meiyun and Assoc. Prof. Yang Bin's team at Shaanxi University of Science & Technology were invited by ACS Applied Materials & Interfaces to contribute a comprehensive review on the preparation, properties, applications, challenges, and prospects of ANF aerogels with different dimensions in the "Functional Aerogels" column.

The article first summarizes the rheological properties of ANF dispersions, various preparation strategies, and drying methods for ANF aerogels. It then reviews the unique characteristics and advantages of ANF aerogels with different morphologies, along with their multifunctional applications in flexible thermal insulation, environmental protection, energy storage, etc. Finally, it discusses the main challenges and prospects, providing insights for scaling up from laboratory to industrial production.

Published in ACS Applied Materials & Interfaces as "Innovations Progress in Emerging Multifunctional Aramid Nanofiber Aerogels", with master's student Wang Yifan as primary author, and Assoc. Prof. Yang Bin and Prof. Zhang Meiyun as corresponding authors.

Fig. 1 Morphology, properties, and applications of ANF aerogels

Highlights:

ANF dispersions can be assembled into various aerogel morphologies (1D fibers, 2D films, 3D monoliths, etc.) through different strategies. The preparation involves three key stages: ANF solution→sol, ANF sol→hydrogel, and ANF hydrogel→aerogel. With low density, high porosity, and toughness, they show great potential in thermal insulation, flame retardancy, environmental protection, energy conversion, flexible sensing, and EMI shielding (Figs. 2, 3).

However, ANF aerogel development remains exploratory. Challenges include: low ANF production efficiency, high costs, immature technology; slow sol-gel conversion, non-continuous solvent exchange/drying processes; and room for improving mechanical properties. Future directions include developing multifunctional ANF composite aerogels with MXene, BNNS, GO, CNT, etc.

Fig. 2 ANF aerogel fabrication processes

Fig. 3 Preparation, properties, applications, and pros/cons of multiform ANF aerogels

Summary/Outlook:
This review covers ANF aerogel preparation, properties, applications, challenges, and prospects. ANF/DMSO solutions can be processed into various dimensional aerogels via wet-spinning, coating, and 3D printing. Benefiting from their porous structure, low density, large surface area, and excellent thermal/chemical stability, ANF aerogels enable efficient applications in insulation, adsorption, energy storage, sensing, information encryption, and thermal management.

Future work should optimize preparation processes and structural regulation to accelerate industrialization, reduce costs, improve mechanical properties, and expand novel applications (Fig. 4).

Fig. 4 Potential development directions for ANF aerogels