Naphth[4]arene: Synthesis,Conformations, and Application in Color-Tunable Supramolecular Crystalline Assemblies

Although the chemistry of macrocyclic arenes has seen rapid development in recent years, the synthesis of new macrocyclic arenes from aromatic rings with no directing groups remains a challenge. In this work, a new macrocyclic arene, naphth[4]arene (NA[4]A), composed of four naphthalene rings bridged by methylene groups, was synthesized using macrocycle-to-macrocycle conversion. NA[4]A shows 1,3-alternate and 1,2-alternate conformations in the solid state, which can be selectively obtained. By supramolecular co-assembly of NA[4]A and 1,2,4,5-tetracyanobenzene (TCNB) in different concentrations and temperatures, two conformation-dependent crystalline luminescent co-assemblies 1,2-NTC and 1,3-NTC can be selectively prepared. Interestingly, the two charge-transfer crystalline assemblies containing NA[4]A with different conformations show bright yellow and green fluorescence, and also display high photoluminescence quantum yields (PLQYs) of 45 % and 43 %. Furthermore, they exhibit color-tunable two-photon excited upconversion emission.     

石墨相氮化碳量子点的简易水热制备和荧光性能

本文以线状石墨相氮化碳(Lg-CN)为原料,在无需强酸加入的情况下,利用简单的纯水中的水热反应成功制得了氮化碳量子点(CN QDs),并利用傅里叶变换红外光谱、X射线粉末衍射、透射电镜、X射线光电子能谱等对所得量子点的形貌和结构进行了表征,进而解释了量子点的形成机理;利用紫外-可见吸收光谱和荧光光谱对其光学性质进行了研...