石墨烯修饰的柔性多彩电热致变色薄膜的制备及性能研究

通过化学氧化还原法并辅以抽滤法制备RGO导电薄膜, 通过丝网印刷法制备变色层, 构筑了多层结构的多彩(红-蓝-白以及橙红-黄-白等)柔性电热致变色薄膜。采用SEM、XRD以及Raman等分析薄膜的结构性质。采用红外热成像以及吸收光谱研究了薄膜(红-蓝-白)的热学以及变色性能。结果表明：当加热时间为3.4 s时, 薄膜温度能达到38℃, 变为蓝色; 当加热时间为6.3 s时, 薄膜温度达到45℃, 变为白色。在较低电压下(6 V), 该薄膜能实现多色彩可逆变色, 其变色时间约为6.3 s, 褪色时间约为9.2 s。该柔性电热致变色薄膜以混合纤维素滤膜为基体, 保证了薄膜良好的柔性, 在可穿戴显示领域有着一定的应用价值。

Preparation and Performance of Reduced Graphene Oxide Functionalized Flexible and Multicolor Electrothermal Chromatic Films

By using a chemical oxidation-reduction method, reduced graphene oxide (RGO) nanomaterials were synthesized. The powder materials were further dispersed in water and filtered to form a RGO film, which was used as a conductive layer. On the other side of the filter paper, a color changing layer was prepared through screen printing. A multicolor (red-blue-white and orange-yellow-white, etc.) and flexible electrothermal chromatic film was then obtained through combining conductive and color changing layers with protecting substrates. The structural properties of the film (red-blue-white) were analyzed by using SEM, XRD and Raman, etc. Their thermal and color-changing properties were studied by using infrared thermal imaging and absorption spectrum. The results show that when surface temperature of the film reaches 38℃ (within 3.4 s under Joule heat treatment at ambient conditions), it turns blue. Further heating to 45℃ (within 6.3 s under Joule heat treatment), it turns white. The multi-color changes are achieved at low working voltage (6 V). After switching off the voltage, the film restores its original color within 9.2 s. The electrothermal chromatic films have good flexibility too, therefore, they might be applied in wearable displays.