Kumar Vishesh, Patel Sunil Kumar, Vyas Ved, Kumar Deepak, Subramaniam Iyer E Siva, Indra Arindam
Department of Chemistry, Indian Institute of Technology (BHU) Varanasi 221005 UP India
School of Chemical and Materials Sciences, Indian Institute of Technology Goa Ponda Goa India
Chem Sci. 2024 Jul 25;15(33):13218-13226. doi: 10.1039/d4sc03023k. eCollection 2024 Aug 22.
Photoredox catalysis involving perovskite quantum dots (QDs) has gained enormous attention because of their high efficiency and selectivity. In this study, we have demonstrated CsPbBr QDs as photocatalysts for the C-N bond formation reaction. The introduction of Ni(dmgH) (dmgH = dimethyl glyoximato) as a cocatalyst with CsPbBr QDs facilitates photocatalytic C-N coupling to form a wide variety of amides. The optimized interaction between the cocatalyst and photocatalyst enhances charge transfer and mitigates charge recombination, ultimately boosting photocatalytic performance. The photocatalytic activity is notably influenced by the variation in the amount of cocatalyst and 7 wt% Ni(dmgH) produces the best yield (92%) of amide. Femtosecond transient absorption spectroscopy reveals that the dynamics of the trap states of QDs are affected by cocatalyst. Further, Ni(dmgH) facilitates molecular oxygen activation to form superoxide radicals, which further initiates the radical pathway for the C-N coupling.
涉及钙钛矿量子点(QDs)的光氧化还原催化因其高效率和选择性而备受关注。在本研究中,我们展示了CsPbBr量子点作为用于C-N键形成反应的光催化剂。引入Ni(dmgH)(dmgH = 二甲基乙二肟)作为与CsPbBr量子点的助催化剂,促进了光催化C-N偶联以形成多种酰胺。助催化剂与光催化剂之间优化的相互作用增强了电荷转移并减轻了电荷复合,最终提高了光催化性能。光催化活性受到助催化剂用量变化的显著影响,7 wt%的Ni(dmgH)产生了最佳的酰胺产率(92%)。飞秒瞬态吸收光谱表明量子点陷阱态的动力学受到助催化剂的影响。此外,Ni(dmgH)促进分子氧活化形成超氧自由基,这进一步引发了C-N偶联的自由基途径。