Nanocellulose-based functional materials for physical, chemical, and biological sensing: A review of materials, properties, and perspectives

As the demand for the Internet of Things (IoTs) continues to surge, smart sensing devices have garnered unprecedented attention. However, the majority of materials used in sensor fabrication exert significant environmental pressure due to their lack of degradability. This necessitates the adoption of environmentally friendly alternatives, such as nanocellulose, a bio-based material. Owing to its unique structure, superior properties, biodegradability, and biocompatibility, nanocellulose is viewed as a promising element for next-generation sensors. This review aims to offer a fresh perspective on the application of nanocellulose in advanced sensors. We commence by briefly discussing the structure, properties, and preparation methods of nanocellulose, followed by an emphasis on its crucial roles in sensors. Subsequently, we delve into recent nanocellulose-based sensing applications, with a particular focus on physical sensors, chemical sensors, and biosensors. The review culminates with a discussion on current challenges and future prospects in nanocellulose-based sensors.