Fig. 1. Visual system for microscopic temperature measurement of porous graphene based on CLCMs. The inset shows the distribution of CLCMs on the porous graphene.

Fig. 2. Characteristics of graphene and CLCMs: (a) Raman spectrum of 3D graphene; (b)–(d) microscopic images of 3D porous graphene with CLCMs at 22, 23.2, and 24.9°C, respectively.

Fig. 3. Temperature dependence on the hue of (a) CLCM 1, (b) CLCM 2, and (c) CLCM 3. The points indicate the experimental data, and the solid lines indicate the fitting curves of the temperature calibration for hue.

Fig. 4. Visual measurement of the microscopic temperature of porous graphene based on CLCMs when the heat transfers from the lower right corner of the porous graphene: images of CLCMs embedded in the porous graphene at the initial temperature when (a) T=0s; (b) T=0.33s; (c) T=1s; (d) T=2s from the video taken by the microscopy imaging system; (e) temperature dependence on the time for the three CLCMs (T: time).