通过共晶工程的选择性外延生长有机异质结构实现光信号定向转换

Selective epitaxial growth of organic heterostructure via cocrystal engineering:Towards oriented signal conversion

分层有机纳米结构(HONs)是一种将具有不同功能的多个成分集成在一个系统中的纳米结构,其在光电子应用中引起了极大的关注.然而,由于不同材料之间结构不相容性的难题,构建具有超低晶格失配率(η)的HONs仍然面临巨大挑战.共晶工程提供了探索合理制备HONs的有力手段,但迄今为止尚未得到系统的证明.在这里,我们展示了一种用于HONs的超低晶格失配异质外延的共晶工程策略.该策略具备足够的通用性,可实现多种材料的集成从而得到不同空间取向的异质结构.通过实验合成了一系列典型HONs,包括三嵌段(η_(1)=0.7%)、分支(η_(2)=0.8%)和核/壳(η_(3)=0.6%)纳米结构,其晶格失配率远低于先前报道的HONs(5%-10%).此外,我们选择性地合成了核/壳的子结构,包括三嵌段和三明治状纳米线,揭示了界面能在HONs形成过程中的诱导作用.作为概念验证,制备所得的不同异质结构成功实现了光子信号的定向转换,为构建下一代集成光电器件奠定了坚实的基础.

The integration of multiple components with different functionalities into a hierarchical organic nanosystem(HON)has attracted significant attention in optoelectronic applications.However,the rational construction of HONs with ultra-low lattice mismatch(η)remains a major challenge due to the inherent structural incompatibility of different materials.Cocrystal engineering holds great promise as a powerful means to explore the controllable fabrication of HONs,but a systematic demonstration has yet to be achieved.Here,we present a cocrystal engineering strategy for ultra-low lattice mismatch heteroepitaxy of HONs,which exhibits sufficient versatility for integrating a variety of materials to construct HONs.Through experimental synthesis,we have realized a series of representative HONs,including threesegment(η_(1)=0.7%),branched(η_(2)=0.8%),and core/shell(η_(3)=0.6%)nanostructures,with lattice mismatch rates significantly lower than those previously reported for HONs(5%-10%).Furthermore,we selectively synthesized substructures of core/shell,including three-segment and sandwich-like nanowires,revealing the role of interface engineering in the formation of unique HONs.As a conceptual validation,the fabricated HONs have successfully achieved oriented photon signal conversion,laying a solid material foundation for constructing the next generation of integrated optoelectronic devices.