Chiral Photonic Liquid Crystal Films Derived from Cellulose Nanocrystals

Abstract

As a nanoscale renewable resource derived from lignocellulosic materials, cellulose nanocrystals (CNCs) have the features of high purity, high crystallinity, high aspect ratio, high Young's modulus, and large specific surface area. The most interesting trait is that they can form the entire films with bright structural colors through the evaporation‐induced self‐assembly (EISA) process under certain conditions. Structural color originates from micro‐nano structure of CNCs matrixes via the interaction of nanoparticles with light, rather than the absorption and reflection of light from the pigment. CNCs are the new generation of photonic liquid crystal materials of choice due to their simple and convenient preparation processes, environmentally friendly fabrication approaches, and intrinsic chiral nematic structure. Therefore, understanding the forming mechanism of CNCs in nanoarchitectonics is crucial to multiple fields of physics, chemistry, materials science, and engineering application. Herein, a timely summary of the chiral photonic liquid crystal films derived from CNCs is systematically presented. The relationship of CNC, structural color, chiral nematic structure, film performance, and applications of chiral photonic liquid crystal films is discussed. The review article also summarizes the most recent achievements in the field of CNCs‐based photonic functional materials along with the faced challenges.

Comparative study on properties of nanocellulose derived from sustainable biomass resources

“…Nanocellulose as a new form of biobased nanomaterials has been receiving an increasing amount of interest from both the scienti c and industrial communities because of their interesting properties, including nanoscale size, bril morphology, large surface area, and good strength (Abitbol et Nowadays, researches on nanocellulose-based materials are springing up like mushroom, which attracted a great concern in the eld of high-performance materials and high technology (Cao et al 2019;Cheng et al 2021a). Thus, biomaterials based on nanocellulose become a hot division in the materials science (Duan et al 2021). Normally, the nanocellulose can be divided into three types: cellulose nanocrystal (CNC), cellulose nano bril (CNF), and bacterial cellulose (BC) (Thomas et al 2018;Yang et al 2015).…”

Nanocellulose‐Based Functional Materials: From Chiral Photonics to Soft Actuator and Energy Storage

“…[111] The resulting chiral liquid crystalline nanostructure with helicoidal organization is the source of brilliant structural colors and is circularly polarized. [112][113][114][115] Meanwhile, helicoidal superstructures have been also found to endow certain living systems with mechanical adaptation against hydrostatic loads and provide better resistance against environmental stresses. [116,117] Chiral nematic LCs, also known as cholesteric LCs, are a type of nematic LCs that are known to have chirality at the molecular level and a nonsuperimposable helicoidal superstructure at the macroscale level.…”

Biomimetic Biomaterials Based on Polysaccharides: Recent Progress and Future Perspectives

“…Besides having superior mechanical performance, materials with chiral nematic structures are mainly investigated for their photonic properties. This subject has been covered in recent reviews, [35][36][37] which highlights its current importance. An interesting example of such materials is the chiral nematic photonic crystal films prepared by Chen and co-workers, [38] who assembled a photoactive polymer with CNCs to form light-and humidity-responsive films.…”

“…Nature may also inspire the preparation of antimicrobial nanostructured systems. [34,35,41] Nanocellulose does not have intrinsic antibacterial activity, but a smart approach reported by Saini and co-workers aimed to address this limitation. [42] CNFs were modified with (3-aminopropyl trimethoxysilane), mimicking the antibacterial activity of chitosan.…”