Li Naiyao, Li Yawen, Wang Zengrong, Cao Tianle, Liu Chenjing, Wang Hongyue, Li Guoping, He Gang
Frontier Institute of Science and Technology, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Key Laboratory of Electronic Devices and Material Chemistry, Engineering Research Center of Key Materials for Efficient Utilization of Clean Energy of Shaanxi Province, Future Industrial Innovation Institute of Emerging Information Storage and Smart Sensor, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710054, P. R. China.
School of Materials Science and Engineering, Chang'an University, Xi'an, Shaanxi Province, 710064, P. R. China.
Angew Chem Int Ed Engl. 2024 Nov 18;63(47):e202410525. doi: 10.1002/anie.202410525. Epub 2024 Sep 12.
Directional electron flow in the photocatalyst enables efficient charge separation, which is essential for efficient photocatalysis of H production. Here, we report a novel class of tetracationic cyclophanes (7) incorporating bipyridine Pt(II) and selenoviologen. X-ray single-crystal structures reveal that 7 not only fixes the distances and spatial positions between its individual units but also exhibits a box-like rigid electron-deficient cavity. Moreover, host-guest recognition phenomena are observed between 7 and ferrocene, forming host-guest complexes with a 1 : 1 stoichiometry. 7 exhibits good redox properties, narrow energy gaps, and strong absorption in the visible range (370-500 nm) due to containing two selenoviologen (SeV) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that 7 has stabilized dicationic biradical, efficient charge separation, and facilitates directional electron flow to achieve efficient electron transfer due to the formation of rigid cyclophane and electronic architecture. Then, 7 is applied to visible-light-driven hydrogen evolution with high hydrogen production (132 μmol), generation rate (11 μmol/h), turnover number (221), and apparent quantum yield (1.7 %), which provides a simplified and efficient photocatalytic strategy for solar energy conversion.
光催化剂中的定向电子流能够实现高效的电荷分离，这对于高效光催化产氢至关重要。在此，我们报道了一类新型的包含联吡啶铂（II）和硒代紫精的四阳离子环番（7）。X射线单晶结构表明7不仅固定了其各个单元之间的距离和空间位置，还呈现出盒状刚性缺电子空腔。此外，在7与二茂铁之间观察到主客体识别现象，形成化学计量比为1∶1的主客体配合物。由于含有两个硒代紫精（SeV）单元，7表现出良好的氧化还原性质、窄能隙以及在可见光范围（370 - 500 nm）内的强吸收。同时，飞秒瞬态吸收（fs - TA）表明，由于刚性环番的形成和电子结构，7具有稳定的二价双自由基、高效的电荷分离，并促进定向电子流以实现高效电子转移。然后将7应用于可见光驱动产氢，具有高产氢量（132 μmol）、产氢速率（11 μmol/h）、周转数（221）和表观量子产率（1.7%），这为太阳能转化提供了一种简化且高效的光催化策略。
