Tuning the aggregation behaviour of BN-coronene diimides with imide substituents and their performance in devices (OLEDs and OFETs)
Tuning the aggregation behaviour of BN-coronene diimides with imide substituents and their performance in devices (OLEDs and OFETs)
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DOI：
10.1039/d1tc02991f
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发表时间：
2021-10-07
影响因子：
6.4
通讯作者：
Staubitz, Anne
中科院分区：
文献类型：
--
作者：
Hoffmann, Jonas;Geffroy, Bernard;Staubitz, Anne
与二萘嵌苯二酰亚胺（PDI）相比，可被视为横向芯延伸的晕苯二酰亚胺（CDIs）对光电器件显示出不期望的影响，诸如吸收降低和蓝移。在这里，我们证明了，如果芯延伸有两个BN单元而不是两个CC单元，则相反：可以实现大的红移，以及更高的摩尔消光系数和有益的发光性质，例如小的斯托克斯位移和高量子产率（phi（lum）> 94%）。这些效应可以通过BN单元对BNCDIs前线分子轨道的影响来解释。在酰亚胺位置，环己基和2，6-二异丙基苯基，不同的取代基序，虽然他们没有在单分子水平上的光学性质的影响，影响的聚集实质上，使在固态的光学性质和在有机器件（OLED和OFFEX）的性能有很大的不同。与主体基质组合，获得具有高达1.5%的EQE和白色光发射（0.317; 0.346）的器件。从区域异构纯的1，7-取代的PDI开始的已开发的合成路线以良好的产率导致BNCDIs，这使得这类化合物非常有前途。
Compared to perylene diimides (PDIs), coronene diimides (CDIs), which can be viewed as a lateral core extension, show undesired effects for optoelectronic devices such as the decrease of the absorption and a hypsochromic shift. Here, we demonstrate that, if the core is extended with two BN units as opposed to two CC units, the opposite is true: large bathochromic shifts can be achieved, together with higher molar extinction coefficients and beneficial luminescence properties, e.g. small Stokes shifts and high quantum yields (phi(lum) > 94%). These effects can be explained by the influence of the BN-unit on the frontier molecular orbitals of the BNCDIs. Different substitution motifs at the imide position, cyclohexyl and 2,6-diisopropylphenyl, although they had no influence on the optical properties on a single molecule level, influenced the aggregation substantially so that the optical properties in the solid state and the performance in organic devices (OLEDs and OFETs) differed considerably. In combination with host matrices, devices with EQEs of up to 1.5% and white light emission (0.317; 0.346) were obtained. The developed synthetic route starting from a regioisomeric pure 1,7-substituted PDI leads to BNCDIs in good yields, which makes this class of compounds very promising.