Fig. 1. Feature maps of self-assembled photonic crystal

Fig. 2. Composite film formed at different ratio of SiO₂/CNC

Fig. 3. SEM images of the SiO₂ film with and without PVP addition，illustration is optical photographs

Fig. 4. Effect of PVP dosage on the performance of CNC/SiO₂/PVP（SiO₂∶CNC=4∶1）composite film under natural light

Fig. 5. Effect of PVP dosage on the performance of CNC/SiO₂/PVP（SiO₂∶CNC=4∶1）composite film under point light

Fig. 6. Effect of PVP dosage on the performance of CNC/SiO₂/PVP（SiO₂∶CNC=1∶4）composite film under natural light

Fig. 7. Effect of PVP dosage on the performance of CNC/SiO₂/PVP（SiO₂∶CNC=1∶4）composite film under point light

Fig. 8. SEM images of different layers in cross section of SiO₂/CNC/PVP（SiO₂∶CNC=4∶1，PVP=2.4%）composite film

Fig. 9. SEM images of different layers in cross section of SiO₂/ CNC /PVP（SiO₂∶CNC=1∶4，PVP=1.2%）composite film

Fig. 10. POM diagrams of different films

Fig. 11. SiO₂/CNC/PVP/PVA（SiO₂∶CNC=1∶4，PVP=0.6%）composite film with different PVA dosage under natural light

Fig. 12. SiO₂/CNC/PVP/PVA（SiO₂∶CNC=1∶4，PVP=0.6 %）composite film with different PVA dosage under point light

Fig. 13. Ultra-depth micrographs of composite films at different PVA dosage

Fig. 14. Effect of PVA dosage on the light transmission of the composite film（the upper right illustration shows the effect of 25% PVA film under external force）

Fig. 15. Effect of PVA dosage on the light transmission of the composite film