Controlling energy flow in multimetallic nanostructures for plasmonic catalysis
Controlling energy flow in multimetallic nanostructures for plasmonic catalysis
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DOI：
10.1038/nnano.2017.131
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发表时间：
2017-10-01
影响因子：
38.3
通讯作者：
Linic, Suljo
中科院分区：
文献类型：
--
作者：
Aslam, Umar;Chavez, Steven;Linic, Suljo
已经表明，等离子体金属纳米颗粒（Ag、Au和Cu）的光激发可以诱导直接的光化学反应。然而，这种技术在催化中的广泛应用受到贵金属表面相对较差的化学反应性的限制。尽管努力将等离子体和催化金属联合收割机，但控制从等离子体金属到催化金属的能量转移的物理机制仍然不清楚。在这里，我们表明，混合核-壳纳米结构，其中核心等离子体金属收获可见光光子可以选择性地将能量引导到纳米结构壳上的催化活性中心。为了实现这一点，我们开发了一种合成协议，存款几个单层的铂到银纳米立方体。该模型系统使我们能够最终分离的混合纳米材料的光学和催化功能，并确定的能量流是强烈偏向于激励的高能电荷载流子在Pt壳。我们证明了这些纳米结构的光催化化学反应中的CO在过量的H-2的优先氧化的效用。我们的数据表明，该反应只发生在Pt表面上。
It has been shown that photoexcitation of plasmonic metal nanoparticles (Ag, Au and Cu) can induce direct photochemical reactions. However, the widespread application of this technology in catalysis has been limited by the relatively poor chemical reactivity of noble metal surfaces. Despite efforts to combine plasmonic and catalytic metals, the physical mechanisms that govern energy transfer from plasmonic metals to catalytic metals remain unclear. Here we show that hybrid core-shell nanostructures in which a core plasmonic metal harvests visible-light photons can selectively channel that energy into catalytically active centres on the nanostructure shell. To accomplish this, we developed a synthetic protocol to deposit a few monolayers of Pt onto Ag nanocubes. This model system allows us to conclusively separate the optical and catalytic functions of the hybrid nanomaterial and determine that the flow of energy is strongly biased towards the excitation of energetic charge carriers in the Pt shell. We demonstrate the utility of these nanostructures for photocatalytic chemical reactions in the preferential oxidation of CO in excess H-2. Our data demonstrate that the reaction occurs exclusively on the Pt surface.