Abstract:
The photodimerization of 4-aminothiophenol (PATP) into 4,4\'-dimercaptobenzene (DMAB) has been extensively utilized as a paradigm reaction to probe the role of surface plasmons in nanoparticle-mediated light-driven processes. Here I report the first observation of the PATP-to-DMAB photoreaction in the absence of any plasmonic mediators. The reaction was observed to occur with different kinetics either for PATP adsorbed on non-plasmonic nanoparticles (TiO2 , ZnO, SiO2 ) or deposited as macroscopic droplets. Confocal microRaman spectroscopy enabled to investigate the reaction progress in different plasmon-free contexts, either aerobic or anaerobic, suggesting a new interpretation of the photodimerization process, based on direct laser-induced activation of singlet oxygen species. These results provide new insights in light-driven redox processes, elucidating the role of sample morphology, light and oxygen.
摘要:
4-氨基苯硫酚(PATP)光二聚成4,4'-二巯基苯(DMAB)已被广泛用作范式反应,以探测表面等离子体在纳米粒子介导的光驱动过程中的作用。在这里,我报告了在没有任何等离子体介质的情况下PATP至DMAB光反应的第一个观察结果。对于吸附在非等离子体纳米颗粒上的PATP(TiO2,ZnO,SiO2)或沉积为宏观液滴。共聚焦显微拉曼光谱能够研究不同无等离子体环境中的反应进展,有氧或厌氧,提出了对光二聚化过程的新解释,基于直接激光诱导的单线态氧物种活化。这些结果为光驱动氧化还原过程提供了新的见解,阐明样品形态的作用,光和氧气