Cascaded charge-transfer organic alloys for the controlled hierarchical self-assembly of low-dimensional heterostructures

Organic alloys integrating intrinsic alloy characters and organic semiconductor advantages demonstrate the multicomponent synergistic and collective effects for desirable structural or functional properties. However, their rational design and the controlled self-assembly of their corresponding heterostructure materials remain yet to be explored. Herein, we fabricated organic charge-transfer (CT) alloys with tunable energy structures and hierarchical heterostructures via a self-assembly process of the cascade CT interaction, which is rationally designed by regulating the weak electron donation and affinity of isomorphic 1,2,4,5-tetracyanobenzene (TCNB)-based CT complexes. The high chemical/structural compatibility between isomorphic CT complexes and their alloys is conducive to the precise preparation of the triblock or core/shell-type organic heterostructures. Impressively, these heterostructures achieve controlled exciton conversion and tunable active/passive photon propagation, benefiting for the nanoscale multiple input/out optical logic gate. Significantly, this strategy could be generalized to other organic CT alloys and hierarchical heterostructures, affording fresh comprehension to materials foundation for integrated optoelectronics.