Simón Marqués Pablo, Castán José María Andrés, Raul Benedito A L, Londi Giacomo, Ramirez Ivan, Pshenichnikov Maxim S, Beljonne David, Walzer Karsten, Blais Martin, Allain Magali, Cabanetos Clément, Blanchard Philippe
MOLTECH-Anjou, UMR CNRS 6200, UNIV Angers, SFR MATRIX, 2 bd Lavoisier, 49045, ANGERS Cedex, France.
Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Chemistry. 2020 Dec 9;26(69):16422-16433. doi: 10.1002/chem.202002810. Epub 2020 Nov 9.
π-Conjugated push-pull molecules based on triphenylamine and 1,1,4,4-tetracyanobuta-1,3-diene (TCBD) have been functionalized with different terminal arene units. In solution, these highly TCBD-twisted systems showed a strong internal charge transfer band in the visible spectrum and no detectable photoluminescence (PL). Photophysical and theoretical investigations revealed very short singlet excited state deactivation time of ≈10 ps resulting from significant conformational changes of the TCBD-arene moiety upon photoexcitation, opening a pathway for non-radiative decay. The PL was recovered in vacuum-processed films or when the molecules were dispersed in a PMMA matrix leading to a significant increase of the excited state deactivation time. As shown by cyclic voltammetry, these molecules can act as electron donors compared to C . Hence, vacuum-processed planar heterojunction organic solar cells were fabricated leading to a maximum power conversion efficiency of ca. 1.9 % which decreases with the increase of the arene size.
基于三苯胺和1,1,4,4-四氰基丁-1,3-二烯（TCBD）的π共轭推拉分子已用不同的末端芳烃单元进行了功能化。在溶液中，这些高度扭曲的TCBD体系在可见光谱中显示出很强的内电荷转移带，且无可检测到的光致发光（PL）。光物理和理论研究表明，由于光激发后TCBD-芳烃部分发生显著构象变化，单线态激发态失活时间非常短，约为10 ps，这为非辐射衰变开辟了一条途径。在真空处理的薄膜中或当分子分散在聚甲基丙烯酸甲酯（PMMA）基质中时，PL得以恢复，导致激发态失活时间显著增加。循环伏安法表明，与C相比，这些分子可作为电子供体。因此，制备了真空处理的平面异质结有机太阳能电池，其最大功率转换效率约为1.9%，且随着芳烃尺寸的增加而降低。
