3D photonic crystals (PCs) have attracted extensive attention due to their unique optical properties, which has shown great potentials in many promising applications. 3D printing technology provides the possibility to conveniently construct 3D structure, which has opened charming new opportunity to fabricate delicate 3D structures with arbitrary geometries in a fully digital fabrication process. Recently, various 3D printing methods, such as nozzle-based 3D printing technologies and light-based 3D writing technologies, have been demonstrated to prepare patterned structural color from various building blocks. Among various structural color materials, the assembly of PCs from monodispersed colloidal nanoparticle suspensions has been intensively explored. In the nozzle-based 3D printing technologies, such as inkjet printing, direct ink writing and fused deposition modeling methods, the limitations of low 3D construction freedom, cumbersome equilibrium coloration process and weak volumetric structural color impede their wide applications. Although effective in constructing fine structures, two-photon polymerization printing is compromised markedly by the print dimension and productivity. The discontinuous 3D printing process can rapidly prepare 3D PCs structure, the limitations of lack of control over the assembly, rough surface and poor fidelity still impede their applications in 3D optical devices.
Optical images of (a) hand model wearing the customized ring structure, (b) Barbie doll wearing the customized earring and necklace structures and (c) colorful koi fish with oriental artistic conception. (d-t) Color and pattern selective optical light-guide tubes.
Here, we demonstrate a continuous digital light processing 3D printing strategy using hydrogen bond assisted colloidal inks for fabricating well-assembled 3D PC structures. Synergistic effect of the stable dispersion of colloidal particles inside UV-curable system induced by hydrogen bonding and the suction force induced by the continuous curing manner cooperatively enable the simultaneous macroscopic printing and microscopic particle assembly, endowing the structure with volumetric color property. Through regulating the particle diameter and printing speed, various complex 3D structures with desired single- or multi-structural color distribution are obtained. Moreover, optical light-guide structures with smooth inner and outer surfaces, low optical loss, as well as the color and pattern selectivity can also be continuously printed. The successful manufacture of 3D structural color with high-fidelity and high-precision will extend the applications in the fields of customized jewelry accessories, decoration and optical device functionalization.
For more details, check out our paper recently published in Nature Communications:
Continuous Resin Refilling and Hydrogen Bond Synergistically Assisted 3D Structural Color Printing
Yu Zhang, Lidian Zhang, Chengqi Zhang, Jingxia Wang, Junchao Liu, Changqing Ye, Zhichao Dong, Lei Wu*, Yanlin Song*
Nature Communications, 2022, 13, 7095