Luo Laiyu, Xiao Xudong, Li Qi, Wang Siyu, Li Yuxin, Hou Jungang, Jiang Baojiang
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, P. R. China.
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
ACS Appl Mater Interfaces. 2021 Dec 15;13(49):58596-58604. doi: 10.1021/acsami.1c17782. Epub 2021 Dec 3.
Photocatalytic generation of singlet oxygen (O) is an attractive strategy to convert organic chemicals to high value-added products. However, the scarcity of suitable active sites in photocatalysts commonly leads to the poor adsorption and activation of oxygen molecules from a triplet state to a singlet state. Here, we report single atomic Cu-N sites on tubular g-CN for the production of singlet oxygen. X-ray absorption fine spectroscopy, in combination with high-resolution electron microscopy techniques, determines the existence of atomically dispersed Cu sites with Cu-N coordination mode. The combined analysis of electron spin resonance and time-resolved optical spectra confirmed that a single atomic Cu-N structure facilitates a high concentration of O generation due to charge transport, electron-hole interaction, and exciton effect. Benefiting from the merits, a single atomic photocatalyst yields nearly 100% conversion and selectivity from thioanisole to sulfoxide within 2.5 h under visible light irradiation. This work deeply reveals the design and construction of catalysts with specific active sites, which are helpful to improve the activation efficiency of oxygen.
光催化产生单线态氧（O）是将有机化学品转化为高附加值产品的一种有吸引力的策略。然而，光催化剂中合适活性位点的稀缺通常导致氧分子从三线态到单线态的吸附和活化较差。在此，我们报道了管状g-CN上的单原子Cu-N位点用于单线态氧的产生。X射线吸收精细光谱结合高分辨率电子显微镜技术确定了具有Cu-N配位模式的原子分散Cu位点的存在。电子自旋共振和时间分辨光谱的联合分析证实，单原子Cu-N结构由于电荷传输、电子-空穴相互作用和激子效应促进了高浓度的O产生。受益于这些优点，单原子光催化剂在可见光照射下2.5小时内从苯甲硫醚到亚砜的转化率和选择性接近100%。这项工作深入揭示了具有特定活性位点的催化剂的设计和构建，这有助于提高氧的活化效率。
