【作者】 孙江晖； 欧阳津； 王岩； 那娜；

【Author】 Jianghui Sun;Jin Ouyang;Yan Wang;Na Na;College of Chemistry, Beijing Normal University;

【机构】 北京师范大学化学学院；

【摘要】 光催化反应由于其能源绿色、条件温和,逐渐成为人们所青睐的一种合成方式。对光催化反应进行在线反应监测,不仅可时刻掌握反应中分子结构变化信息,还可进行实时调控和快速优化,也为反应机理的研究提供可靠实验依据。我们前期先后采用光谱技术对催化反应进行监测和机理研究[1,2],但仍只能通过间接光谱信息进行分析。常压质谱技术是直接获取分子结构信息的主要手段之一,具有分析速度快、无需样品预处理等优点[3,4]。我们前期基于常压质谱技术,对酶催化反应进行了初步研究[5,6]。在本工作中,我们继续利用多相液流萃取电喷雾常压离子源(MF-EESI)研究光催化反应,基于辅助载气的气动喷雾实现反应溶液的快速抽提,辅以辅助液流增加了其离子化性能,喷雾与质谱进样口的垂直设置降低了背景干扰。进而对Ti O2光催化合成吩嗪类化合物的反应过程进行了监测,并推导了相关机理。该方法在复杂反应的研究中具有一定优势,也为光催化领域的发展提供了可靠的研究平台。更多还原

【Abstract】 Photocatalytic reaction has obtained much attention based on green energies and mild conditions. Real-time monitoring of photoreaction can provide molecular information, achieve rapid optimizations, and make contributions on mechanism studies. We have achieved indirect monitoring of catalytic reactions by spectroscopy methods [1,2]. For obtaining direct molecular information, ambient mass spectrometry（AMS） can be one of important methods [3,4]. Recently, we applied AMS to study enzyme catalytic reactions [5,6]. Here, we continued to examine photocatalytic reaction by using multiphase flow of extractive electrospray ionization（MF-EESI）. The rapid extraction of analytes from reaction system was obtained by auxiliary carrier gas, and ionization efficiency was increased by concentric-sprayed solvent. Furthermore, mixed-spray was perpendicular to the MS inlet, which would be in favor of decreasing background signals. Therefore, TiO₂-photocatalytic reaction of C-N bond formation to obtain phenazines was monitored and reaction mechanism was deduced, providing a reliable platform for studies on organic reactions.更多还原