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Nanocellulose, typically cellulose nanocrystals (CNCs), has excellent properties and is widely used. In particular, CNC has a small dimension, high chemical reactivity, and high sustainability, which makes it an excellent candidate as a starting material to be converted into nanocellulose derivatives. Chemical modification is essential for obtaining the desired products; the modifications create different functional attachment levels and generate novel microstructures. Recent advances on nanocellulose derivatives have not yet been reviewed and evaluated for the last five years. Nanocellulose derivative materials are being used in a wide variety of high-quality functional applications. To meet these requirements, it is essential for researchers to fully understand CNCs and derivative materials, precisely their characteristics, synthesis methods, and chemical modification approaches. This paper discusses CNC and its derivatives concerning the structural characteristics, performance, and synthesis methods, comparing the pros and cons of these chemical modification approaches reported in recent years. This review also discusses the critical physicochemical properties of CNC derivative products, including solubility, wetting performance, and associated impacts on properties. Lastly, this paper also comments on the bottlenecks of nanocellulose derivatives in various applications and briefly discusses their future research direction.

In the past few years, nanocellulose, as a new‐emerging colloid, has developed into a large family and gained increasing attention owing to its favorable properties. It represents a ubiquitous feature in electronics as different components according to principles extend across energy, lighting management, and transistors and biosensors to information technologies. Within these decades, there are a lot of remarkable phenomena, effects, and performances relevant to a few additional attributes of nanocellulose, making the electronics perform better and better. Toward the rapid nanotechnology development and the need of the society, characterizing this important nanomaterial and making more and more new electronics have become important things to be done. This review consolidates the contribution of nanocellulose to nano‐related electronics, summarizes these methods to utilize nanocellulose as any component in devices, and points out the attributes of the nanocellulose. In the devices, the recent advances into solid‐state electronics, optoelectronic devices, and flexible/wearable electronics are categorized. The intrinsic electrical, dielectric and electronic structures, and properties of nanocellulose related to the device performances are particularly summarized and analyzed, which is believed beneficial in providing a judgment criterion for devices in the future.

A dielectric material is a particular type of insulator that does not conduct electricity but gets polarized when subjected to electricity, which is a crucial part of electronics such as cables, capacitors, displays, transformers, etc. Currently, synthesizing a nonpolar dielectric remains challenging. In this study, a method to make a high dielectric and nonpolar fluoropolymer and its nanocomposites based on cellulose nanocrystals (CNCs) by grafting it with nonpolar polymer 2,2,2-trifluoroethyl methacrylate is reported. A high dielectric constant but nonpolar nanocellulose material is obtained for the first time. This material has an anisotropic arrangement of dipoles with a high polarizability effect, thereby displaying excellent dielectric properties (e.g., dielectric constant and loss: 8.59 and 0.017 at 10 kHz) and high stability (dielectric constant at 8.21 at 1 MHz). The dielectric material is miscible as an additive with other commercial fluoropolymer plastic, which demonstrates a high breakage voltage ranging from 4.6 to 9.2 kV/0.1 mm. When it is used as an interfacial layer in electrowetting display devices, it also demonstrated a low voltage driven and fast-response effect. The excellent dielectric performances allow to develop more high-performance dielectrics and electronics such as memories, sensors, actuators, wires, and film capacitors.

As a biodegradable green dielectric material, cellulose has been used in wearable electronic devices, sensors, film capacitors, and other electronic devices. Cellulose-based dielectric has the advantages of renewable, non-toxic, flexible, and strong mechanical properties, so it of is great significance to study the dielectric properties of cellulose. In this paper, we summarized the factors influencing the dielectric properties of cellulose-based dielectric and the ways to change the dielectric properties, mainly explored the methods to improve the dielectric constant of nanocellulose-based dielectric materials. This review summarizes the current state-of-art progress of new dielectric materials, the application of cellulose in electronic devices, the development of green energy storage materials and etc.