Structure-Tunable Construction of Colloidal Photonic Composites via Kinetically Controlled Supramolecular Crosslinking

Colloidal photonic composites (CPCs) combine a unique array of colloidal particles (CPs) with a polymer matrix and exhibit intriguing optical and mechanical properties strongly depending on their structures. One-step construction of CPCs with tunable structures is crucial for enriching their properties and matching application requirements, which is highly desirable yet challenging. Here, we present a general strategy for CPC construction with tunable structures from short-range to long-range order by one-step kinetically controlling the supramolecular crosslinking between CPs and supramolecular oligomers. Importantly, the assembly process is monitored in situ and the key factors for structural regulation, i.e., the critical volume fraction of CPs and the structural transition from crystal growth to lattice compression, are disclosed, which play critical roles in obtaining CPCs with a wide range of controllable structures. The as-obtained CPCs exhibit structural colors with different angle dependencies, versatile mechanical strengths, and appealing mechanochromic and self-healing capabilities. This work provides insights into the one-step construction of structure-tunable photonic materials, opening up exciting avenues for novel solution-processable photonics.