Sequencing and Welding of Molecular Single-Crystal Optical Waveguides

Molecular crystals are promising anisotropic optical transducing media for next-generation optoelectronic microdevices that will be capable of secure transduction of information and impervious to external electromagnetic interference. However, their full potential has not been explored yet due to their poor processability, low mechanical compliance, pronounced brittleness and high proneness to cracking that often result in irrecoverable damage. These issues are detrimental to their ability to transduce light. Here, a novel strategy is presented based on 3D epitaxial crystal growth of organic/inorganic crystals based on charge-assisted hydrogen bonds that can be used to efficiently weld broken molecular single-crystalline optical waveguides and restore their light-transducing capability. This approach can also be applied to prepare asymmetric multidomain crystalline heterostructures starting from isostructural molecular tectons, resulting in novel opto/electro/mechanical functionalities in the hybrid materials. It also removes an important obstacle toward wider application of molecular crystals in the next-generation optoelectronics.