Use of carbon dots to enhance UV-blocking of transparent nanocellulose films

作者：Feng, Xin^*; Zhao, Yafei; Jiang, Yaoquan; Miao, Miao; Cao, Shaomei; Fang, Jianhui

来源：Carbohydrate Polymers, 2017, 161: 253-260.

DOI：10.1016/j.carbpol.2017.01.030

• Bamboo
• Nanocellulose
• Carbon dots
• Transparent UV-blocking film
• Thermal stability

High-efficient transparent UV-blocking nanocellulose (NC) films were successfully assembled by pressured-extrusion of the composites of carbon dots (CDs), 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) radical mediated oxidized nanocellulose (ONC) and ZnO nanostructures. ONC nanofibrils were firstly extracted from bamboo fibers and subsequently prepared by applying TEMPO oxidation. The as obtained CDs-ONC-ZnO films exhibited high visible light transparency, excellent thermal stability and enhanced UV-blocking properties. Compared to the previously designed NC-ZnO films, CDs-ONC-ZnO films presented significant increase of UV-blocking ratio (UVR) with the same amounts of ZnO. Moreover, the UVR of CDs-ONC-s-ZnO film with 4 wt% sheet-like ZnO (s-ZnO) at 300 nm and 225 nm is 92.74% and 98.99%, better than the same condition of CDs-ONC-b-ZnO film added with belt-like ZnO (b-ZnO) and CDs-ONC-p-ZnO film added with commercial particulate ZnO (p-ZnO). An interesting discovery is that when adding 4 wt% p-ZnO, the UVR of CDs-ONC-p-ZnO film is very close to the value of NC-s-ZnO film with the same amount of s-ZnO.

• 出版日期2017-4-1
• 单位上海大学