Multifunctional Nanocellulose for Sustainable Applications: From Preparation to Performance

Nanocellulose, a renewable material derived from cellulose, has gained significant attention as a sustainable alternative to petroleum-based materials. Owing to its biodegradability, high mechanical strength, large surface area, and tunable surface chemistry, nanocellulose offers great potential for its diverse applications. This review provides a comprehensive analysis of nanocellulose fundamentals, including its structure, sources, and major types, followed by an in-depth evaluation of its diverse application landscape. Particular emphasis is placed on recent technological advancements in biomedical engineering, food packaging, water and wastewater treatment, electronics, energy devices, and emerging multifunctional composites. The review highlights how tailored surface modifications and hybrid material designs significantly enhance nanocellulose’s barrier, antimicrobial, mechanical, electrochemical, and adsorptive properties, enabling next-generation materials with improved performance and sustainability. Key challenges, including moisture sensitivity, thermal instability, aggregation behavior, scalability constraints, and characterization inconsistencies, are critically discussed. The study concludes by outlining prospects that include smart and responsive nanocellulose systems, advanced composites, and industrial pathways for integrating nanocellulose into high-value applications. Overall, this work synthesizes recent progress and provides strategic insights for advancing nanocellulose as a versatile material platform for sustainable and high-performance technological solutions.