Cellulose nanocrystals (CNC) iridescent films composed of the chiral nematic liquid crystal phase have attracted much attention owing to their fascinating optical properties. Herein, we summarized and discussed the recent advances in preparing iridescent CNC film via vacuum-assisted self-assembly (VASA) method, which has the advantage to fabricate large area, highly oriented and structurally homogeneous CNC liquid crystal film. The discussed aspects include (i) Factors that influence the self-assembly behavior of CNC nanorods during VASA. (ii) The strategy for modifying the optical, thermal as well as the mechanical properties of VASA assisted CNC iridescent film. (iii) Co-assembling of CNC liquid crystal phase and other functional nanoparticles by VASA technique. In all cases, key issues are highlighted and future developments that we consider as the most relevant are identified. Furthermore, future research activities are suggested in the conclusion.

由手性向列液晶相组成的纤维素纳米晶体（CNC）虹彩膜由于其迷人的光学性能而备受关注。本文中，我们总结并讨论了通过真空辅助自组装（VASA）方法制备虹彩CNC薄膜的最新进展，该优势具有制造大面积，高取向和结构均匀的CNC液晶薄膜的优势。讨论的方面包括（i）在VASA期间影响CNC纳米棒自组装行为的因素。（ii）修改VASA辅助的CNC虹彩膜的光学，热以及机械性能的策略。（iii）通过VASA技术将CNC液晶相和其他功能性纳米粒子共同组装。在所有情况下，重点突出了关键问题，并确定了我们认为最相关的未来发展。此外，结论中建议了未来的研究活动。