Metal Nanoparticle-Catalyzed Reduction Using Borohydride in Aqueous Media: A Kinetic Analysis of the Surface Reaction by Microfluidic SERS.
Metal Nanoparticle-Catalyzed Reduction Using Borohydride in Aqueous Media: A Kinetic Analysis of the Surface Reaction by Microfluidic SERS.
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DOI：
10.1002/anie.201605776
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发表时间：
2016-10
影响因子：
--
通讯作者：
W. Xie;Roland Grzeschik;S. Schlücker
中科院分区：
文献类型：
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作者：
W. Xie;Roland Grzeschik;S. Schlücker
氢化物广泛用于还原反应。在质子溶剂中，它们的水解产生分子氢作为第二还原剂。这两种平行还原途径之间的竞争迄今为止一直被忽视，因为两者通常产生相同的产物。我们研究了铂催化还原4-硝基苯硫酚4-氨基苯硫酚在硼氢化钠水溶液作为一个突出的模型反应，通过使用无标记的Sers监测在微流控反应器中。动力学分析表明，强烈的pH依赖性。令人惊讶的是，仅在pH>13时，还原仅由硼氢化钠驱动。这项研究表明了基于微流体的动力学Sers监测胶体悬浮液中的多相催化的潜力。
Hydrides are widely used in reduction reactions. In protic solvents, their hydrolysis generates molecular hydrogen as a second reducing agent. The competition between these two parallel reduction pathways has been overlooked so far since both typically yield the same product. We investigated the platinum-catalyzed reduction of 4-nitrothiophenol to 4-aminothiophenol in aqueous sodium borohydride solution as a prominent model reaction, by using label-free SERS monitoring in a microfluidic reactor. Kinetic analysis revealed a strong pH dependence. Surprisingly, only at pH>13 the reduction is driven exclusively by sodium borohydride. This study demonstrates the potential of microfluidics-based kinetic SERS monitoring of heterogeneous catalysis in colloidal suspension.