Efficient Preparation of Cellulose Nanofibers in High Yield Using Low Concentration of Organic Acid

Abstract Cellulose nanofibers as one of the promising cellulose‐based nanomaterials have received increasing attention on account of its excellent properties and wide application prospect. Owing to the robust structure of cellulose with strong hydrogen bonds, achieving the uniform cellulose nanofibers from cellulose sources under mild conditions remains challenging. Here we developed an efficient strategy to acquire cellulose nanofibers with high yield using low concentration of organic acid. Electron microscopic characterization showed that the uniform cellulose nanofibers with an average diameter of 27±8 nm was prepared through only 5 wt% triflic anhydride hydrolysis followed by high‐pressure homogenization. And the yield of cellulose nanofibers reached up to 81%. Moreover, the triflic anhydride acted in synergy to break the glycosidic bonds in amorphous region and change the hydrogen bonding network of cellulose. Cellulose nanofibers displayed the high crystallinity index of 84% and good thermal stability with the T max of 331 °C. Our strategy offers an eco‐friendly and sustainable approach for the high‐yield preparation of cellulose nanofibers.