Chiral cellulose nanocrystals have unique optical properties and are of great research and application value

Cellulose nanocrystals (CNC) are nanoscale cellulose extracted from natural fibers. They have nanostructure characteristics, high crystallinity, high purity, high strength, high elastic modulus, good biocompatibility, and biodegradability. It has the advantages of degradation and unique optical properties. Cellulose nanocrystals are a type of nanocellulose, and nanocellulose is a type of chiral photonic material. Cellulose nanocrystals can self-assemble to form a chiral nematic helical structure. Chiral cellulose nanocrystals have circularly polarized light characteristics and are cholesteric liquid crystal materials.

Chirality is the phenomenon that an object and its mirror image cannot overlap. It is a basic attribute ubiquitous in natural materials and has become an important research direction in many disciplines. Compared with other chiral photonic materials, chiral cellulose nanocrystals are easier to obtain, have cost advantages, are biocompatible, and have excellent optical properties, so they have attracted much attention. Chiral cellulose nanocrystals can be used alone to prepare functional optical films and other materials, or they can be used in combination with other materials to create new chiral structural nanomaterials, such as being co-assembled with gold nanorods to form a chiral nematic film.

According to the “Chiral Cellulose Nanocrystal Industry In-depth Market Research and Investment Strategy Suggestions Report 2021-2025” released by the Industrial Research Center It shows that the chiral nematic helical structure formed by the self-assembly of chiral cellulose nanocrystals can selectively reflect light of different wavelengths, produce structural colors, and respond quickly to external stimuli such as light, electricity, force, and heat. Structural color adjustment can then be achieved. Using this characteristic of chiral cellulose nanocrystals, we can imitate the bright colors of butterfly wings and the discoloration effect of chameleon skin to achieve bionic color change.

Chiral cellulose nanocrystals can use external stimuli to achieve structural color changes and are of great value in the development of color-changing materials and stealth materials. This technology can be used in both military and civilian fields. Using the properties of chiral cellulose nanocrystals, scientific researchers are also developing new sensors, filters, displays, optical devices, and new materials. Therefore, chiral cellulose nanocrystals are widely used in biology, medicine, optics, physics, catalysis, etc. , electronics, optical instruments, information storage, information encryption, optical anti-counterfeiting and other fields all have important research value.

Industry analysts said that chiral cellulose nanocrystals have the characteristics of difficulty in controlling the chiral structure during preparation, long film formation time, and Characteristics such as uneven thickness, susceptibility to water, and easy cracking limit its mass production and large-scale application, so its technical research is still in depth. In my country, scientific research institutions and universities such as Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Qingdao University of Science and Technology, Nanjing Forestry University, Northeast Forestry University, Jilin University, etc. are conducting research on chiral cellulose nanocrystals; abroad, the Chiral Cellulose Nanocrystal Research Institute All Northeastern University in the United States, University of British Columbia in Canada, University of Göttingen in Germany, etc.