Chen Ye-Tao, Wen Xinyi, He Jiaxing, Li Zhanhua, Zhu Sheng, Chen Wenbin, Yu Jierong, Guo Yan, Ni Shaofei, Chen Shunli, Dang Li, Li Ming-De
Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, China.
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710127, China.
ACS Appl Mater Interfaces. 2022 Jun 29;14(25):28781-28791. doi: 10.1021/acsami.2c03940. Epub 2022 Jun 16.
Organic cocrystal exhibits excellent photothermal conversion (PTC), but how the intermolecular interactions of cocrystals regulate the PTC is obscure. Here, two isomeric donor molecules (phenanthrene and anthracene) and two electron-withdrawing molecules (7,7,8,8,8-tetracyanodimethylquinone and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinone dimethane) are self-assembled into the four cocrystals (PTQ, PFQ, ATQ, and AFQ). By changing the molecular configuration of the donor and the electron-withdrawing ability of the acceptor, the intrinsic influencing factors of the intermolecular interaction on the PTC were explored. Under near-infrared laser (808 nm) irradiation, the PTC efficiencies of PTQ, PFQ, AFQ, and ATQ are 35.85, 44.74, 57.00, and 60.53%, respectively. Based on the single-crystal X-ray diffraction, ultrafast time-resolved transient absorption, and excited-state theoretical calculations, we found that the π-π stacking in ATQ and AFQ is conducive to promoting the near-infrared light-harvesting ability and the p-π interaction of cocrystals can regulate the nonradiative rotation of -C(C≡N) groups, resulting in a tunable near-infrared PTC via the isomeric cocrystals. Accordingly, the evaporation rate of the porous polyurethane-AFQ foam can reach 1.33 kg·m·h in the simulated solar-driven water evaporation system. This work provides a strategy to boost the PTC by the intermolecular interactions of cocrystal materials.
有机共晶表现出优异的光热转换（PTC）性能，但共晶的分子间相互作用如何调节PTC尚不清楚。在此，两种同分异构的供体分子（菲和蒽）与两种吸电子分子（7,7,8,8,8-五氰基二甲苯醌和2,3,5,6-四氟-7,7,8,8-四氰基对苯二醌二甲烷）自组装形成四种共晶（PTQ、PFQ、ATQ和AFQ）。通过改变供体的分子构型和受体的吸电子能力，探索了分子间相互作用对PTC的内在影响因素。在近红外激光（808 nm）照射下，PTQ、PFQ、AFQ和ATQ的PTC效率分别为35.85%、44.74%、57.00%和60.53%。基于单晶X射线衍射、超快时间分辨瞬态吸收和激发态理论计算，我们发现ATQ和AFQ中的π-π堆积有利于促进近红外光捕获能力，共晶的p-π相互作用可以调节-C（C≡N）基团的非辐射旋转，从而通过同分异构共晶实现可调谐的近红外PTC。因此，在模拟太阳驱动水蒸发系统中，多孔聚氨酯-AFQ泡沫的蒸发速率可达1.33 kg·m⁻²·h。这项工作提供了一种通过共晶材料的分子间相互作用来提高PTC的策略。
