 Cellulose nanocrystals, CNCs, or cellulose nanofibers, CNFs, with different morphologies, properties can be obtained through enzymatic, chemical, or mechanical treatment of microcrystalline cellulose. Tempo-mediated oxidation leads to a decrease in fiber length and an increase in degree of crystallinity of the fibers as compared to mechanical treatment and ultrasonication, introducing carboxyl functional groups, COOH, on the surface of the fibrils for further chemical functionalization. This article was authored by Edwin S. Medivli, Patrick G. Kauru, Antony N. Gachanga, and others.