▎ 摘　　要

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 degrees C (within 3.4 s under Joule heat treatment at ambient conditions), it turns blue. Further heating to 45 degrees C (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.