Flexible Intelligence on a Green Skeleton: Progress and Challenges of CNF-Enabled Multimodal Sensing Platforms

Area of Science:

• Materials Science
• Nanotechnology
• Green Chemistry

Background:

• Cellulose nanofibrils (CNFs) are abundant, mechanically strong, and biocompatible materials.
• CNFs possess easily engineered surfaces, making them ideal for next-generation flexible sensors.
• Recent advancements focus on sustainable and low-carbon manufacturing processes for CNFs.

Purpose of the Study:

• To review recent progress in low-carbon cellulose nanofibril (CNF) manufacturing.
• To elucidate the mechanisms governing CNF-based materials in various sensing applications.
• To identify bottlenecks and future prospects for industrial deployment of CNF sensing technologies.

Main Methods:

• Review of literature on CNF manufacturing (biomass pretreatment, fibrillation, functionalization) from the past five years.
• Analysis of CNF films, aerogels, and hydrogels in humidity, temperature, strain/pressure, optical, electrochemical, and biosensing platforms.
• Investigation of multiscale conductive networks, surface-charge regulation, and dynamic crosslinking strategies.

Main Results:

• Low-carbon CNF manufacturing techniques have advanced significantly.
• Specific material designs enhance sensor sensitivity, linear response, and environmental tolerance.
• Key challenges for scale-up include energy demand, variability, and integration.

Conclusions:

• CNF-based sensing technologies show promise for industrial applications.
• Future directions include recycling, digital printing, and self-powered/self-healing architectures.
• Sustainable design and integrated functionalities are crucial for future development.