Cellulose Hollow Annular Nanoparticles Prepared from High-Intensity Ultrasonic Treatment

• Published in: ACS nano Vol. 16; no. 6; pp. 8928 - 8938
• Main Authors: Xu, Yongjian, Gao, Minlan, Zhang, Yongqi, Ning, Lulu, Zhao, Deqing, Ni, Yonghao
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 28.06.2022
• Subjects: high-intensity ultrasonic treatment; spherical aberration-corrected transmission electron microscopy; hollow structure; hollow-type annular CNCs; cellulose nanocrystals
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.1c11167

Cellulose nanomaterials, such as cellulose nanocrystals (CNCs), have received enormous attention in various material research fields due to their unique properties and green/sustainable nature, among other qualities. Herein, we report hollow-type annular cellulose nanocrystals (HTA-CNCs), which are generated by following a high-intensity ultrasonic treatment. The advanced aberration-corrected transmission electron microscopy results reveal that HTA-CNCs exhibit ring structures with a typical diameter of 10.0–30.0 nm, a width of 3.0–4.0 nm, and a thickness of 2.0–5.0 nm, similar to those of elementary crystallites. The X-ray diffraction measurements show that the as-prepared HTA-CNCs maintain the cellulose I structure. The changes in structure and hydrogen-bonding characteristics of HTA-CNCs are further determined based on the FT-IR results after deconvolution fitting, showing that three types of hydrogen bonds decrease and the content of free OH increases in HTA-CNCs compared with those in the original CNCs. Furthermore, molecular dynamics simulation is carried out to support the experimental study. The formation of HTA-CNCs might be attributed to the structural change and entropy increase. The hollow-type annular CNCs may have broad value-added applications as cellulose nanomaterials in different fields.