通过自组装,环境友好的纤维素纳米晶体(CNCs)可以形成具有光子晶体结构的薄膜,其间距大小可以在制造阶段以各种方式进行调整。此外,这些电影对多种刺激表现出反应性能,它提供了广泛的应用。聚(乙二醇)(PEG)和CNCs结合以形成较小的手性向列域,其在缓慢干燥时形成具有均匀螺旋结构的固体膜。通过改变CNCs和PEG的组成,制备了具有从蓝色到红色的均匀结构颜色的柔性和平坦的光子复合膜。受益于通过将水分子插入和分离到手性向列型结构中而改变的间距大小,CNCs膜和CNC-PEG复合膜响应于不同湿度表现出可逆的结构颜色变化。此外,由甘油和CNCs的组合形成的手性向列膜对盐酸气体具有可逆的刺激响应。同样,调节甘油的比例可以控制薄膜的间距大小,因此,反射的颜色。总之,薄膜的光子晶体结构的间距大小可以通过调节添加剂的比例来精确地调整,制备的两种薄膜对湿度和盐酸气体具有可逆响应,分别。基于CNC的薄膜在比色生物传感器的应用中显示出希望。
Through self-assembly, environmentally friendly cellulose nanocrystals (CNCs) can form films with a photonic crystal structure whose pitch size can be adjusted in a variety of ways at the fabrication stage. Moreover, the films exhibit response performance to multiple stimuli, which offers extensive applications. Poly(ethylene glycol) (PEG) and CNCs combine to form a smaller chiral nematic domain that develops a solid film with a uniform spiral structure when slowly dried. By changing the composition of CNCs and PEG, flexible and flat photonic composite films with uniform structural colors from blue to red are prepared. Benefiting from the change in pitch size by insertion and detachment of water molecules into the chiral nematic structure, CNCs films and CNC-PEG composite films exhibit a reversible structural color change in response to different humidity. In addition, the chiral nematic films formed by the combination of glycerol and CNCs have a reversible stimulation response to hydrochloric acid gas. Similarly, adjusting the ratio of glycerol can control the pitch size of the films and, thus, the reflective color. In summary, the pitch size of the photonic crystal structure of the films can be precisely tuned by regulating the additive ratio, and the two prepared films have reversible responses to humidity and hydrochloric acid gas, respectively. The CNC-based films show promise in the application of colorimetric biosensors.