Full-Spectrum Photonic Pigments with Non-iridescent Structural Colors through Colloidal Assembly


  • This research is supported by an International Collaboration grant (Sunjin-2010-002) from the Ministry of Trade, Industry & Energy of Korea. We also acknowledge support from the Harvard MRSEC through the NSF (DMR-0820484). This work is performed in part at the Center for Nanoscale Systems (CNS) at Harvard University, which is supported by the National Science Foundation (ECS-0335765). We also thank Prof. Gi-Ra Yi from Sungkyunkwan University for helpful discussions.


Structurally colored materials could potentially replace dyes and pigments in many applications, but it is challenging to fabricate structural colors that mimic the appearance of absorbing pigments. We demonstrate the microfluidic fabrication of “photonic pigments” consisting of microcapsules containing dense amorphous packings of core–shell colloidal particles. These microcapsules show non-iridescent structural colors that are independent of viewing angle, a critical requirement for applications such as displays or coatings. We show that the design of the microcapsules facilitates the suppression of incoherent and multiple scattering, enabling the fabrication of photonic pigments with colors spanning the visible spectrum. Our findings should provide new insights into the design and synthesis of materials with structural colors.