Graduate School of Human and Environmental Studies, Kyoto University, Yoshida Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan.
Phys Chem Chem Phys. 2018 Nov 21;20(45):28375-28381. doi: 10.1039/c8cp04292f.
Upon photoirradiation with visible light, a pyridine molecule adsorbed on a TiO2 surface can be photoexcited to give a pyridine radical cation via ligand-to-metal charge transfer (LMCT) between pyridine and titanium. This leads to dehydrogenative cross-coupling (DCC) between pyridine and cyclohexane with concomitant hydrogen evolution. Since the radical cation can selectively oxidize cyclohexane to a cyclohexyl radical, the cross-coupling between pyridine and cyclohexane proceeds with higher selectivity compared with that in photocatalysis by TiO2 under UV irradiation.
在可见光照射下，吸附在 TiO2 表面的吡啶分子可以通过吡啶和钛之间的配体到金属电荷转移（LMCT）被光激发为吡啶自由基阳离子。这导致吡啶和环己烷之间的脱氢交叉偶联（DCC）以及伴随的氢气释放。由于自由基阳离子可以选择性地将环己烷氧化为环己基自由基，因此与 TiO2 在紫外光照射下的光催化相比，吡啶和环己烷之间的交叉偶联具有更高的选择性。
