Organic Cocrystal Functional Materials:Design,Synthesis And Application

Rencently,organic cocystal engineering has developed to be a novel design strategy towards functional materials.Organic cocrystal is a multi-component crystal that composed of two or more components,which can recognize each other through intermolecular non-covalent interactions and co-assembly into an ordered structure with a fixed stoichiometry ratio.Different from single-component materials,organic cocrystals can not only maintain the porperty of single-component materials,but also exhibit novel functional properties that are rare among organic materials,such as ambipolar charge transport,white light emission,room temperature ferroelectricity,room temperature phosphorescence and so on.As a consequence,the exploration of the relationship between the intermolecular interactions,cocrystal packing structures and their functional properties would not only be beneficial to the in-depth understanding of cocrystals,but also guide the design of organic functional cocrystals,which would further in favor of the design of high-performance,multifunctional organic materials and promote their practical applications.Therefore,we here mainly focus on the design and application of organic cocrystals,together with the revelation of structure-property relationship in organic cocrystal systems.The main innovations are as follows:1.We designed and synthesized a 1D multifunctional corannulene-fullerene cocrystals with both high electron transport and sensitive light detection ability.The significant 1D morphology is dominated by the strong concave-convex π-π interaction.The dense stacking structure in cocrystal provides an effective channel for electron transport and that make it suitable for the fabrication of high-performance field-effect transistors.Moreover,the charge transfer interaction between the donors and acceptors promotes it to apply in sensitive photodetectors.Therefore,this work provides a good reference for designing and synthesizing multifunctional materials in the future.2.We designed and synthesized the first 2D infrared photothermal conversion cocrystal,which serves as a reference for rational design of infrared cocrystal materials.The strong charge transfer between the donors and acceptors leads to the infrared absorption of the cocrystal,while the effective fluorescence quenching and rapid non-radiative transition in the cocrystal make it a high-performance photothermal conversion material,which could be applied in real-time and time-resolved photothermal imaging.3.We designed and synthesized a novel 2D infrared cocrystal based on porphyrin-fullerene.The strong charge-transfer interaction and π-π interaction result in the 2D growth of cocrystal,which promotes the successful fabrication of centimeter-scale cocrystal crystalline films.Vertical photodetectors based on the crystalline film exhibit high-performance photoresponse property with a wide spectral response range,which provide a reference for the construction of image sensors with high integrated density.