Abstract This work presents the visible-light photocatalytic selective oxidation of thiols to disulfides with molecular oxygen (O2) on anatase TiO2. The high specific surface area of anatase TiO2 proved to be especially critical in conferring high photocatalytic activity. Herein, surface complexation between thiol and TiO2 gives rise to photocatalytic activity under irradiation with 520 nm green light-emitting diodes (LEDs), resulting in excellent reaction activity, substrate scope, and functional group tolerance. The transformation was extremely efficient for the selective oxidation of various thiols, particularly with substrates bearing electron-withdrawing groups (reaction times of less than 10 min). To date, the longest wavelength of visible light that this system can utilize is 520 nm by the surface complex of substrate-TiO2. Importantly, O2 was found to act as the electron and proton acceptor, rather than to incorporate into the substrates. Our findings regarding this surface complex-based photocatalytic system can allow one to understand the interaction between the conduction band electrons and O2.

中文翻译：

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在锐钛矿型 TiO2 上可见光光催化选择性有氧氧化硫醇为二硫化物

摘要 这项工作介绍了在锐钛矿型 TiO2 上用分子氧 (O2) 将硫醇选择性氧化为二硫化物的可见光光催化。锐钛矿 TiO2 的高比表面积被证明在赋予高光催化活性方面尤其重要。在此，硫醇和 TiO2 之间的表面络合在 520 nm 绿色发光二极管 (LED) 的照射下产生光催化活性，从而产生优异的反应活性、底物范围和官能团耐受性。这种转化对于各种硫醇的选择性氧化非常有效，特别是对于带有吸电子基团的底物（反应时间小于 10 分钟）。迄今为止，该系统可以利用的最长可见光波长为 520 nm，由基材-TiO2 的表面复合物构成。重要的，发现 O2 充当电子和质子受体，而不是结合到基板中。我们关于这种基于表面复合物的光催化系统的发现可以让人们了解导带电子和 O2 之间的相互作用。