Revealing the Role of Interfacial Properties on Catalytic Behaviors by in Situ Surface-Enhanced Raman Spectroscopy
Revealing the Role of Interfacial Properties on Catalytic Behaviors by in Situ Surface-Enhanced Raman Spectroscopy
复制标题
通过原位表面增强拉曼光谱揭示界面性质对催化行为的作用
DOI：
10.1021/jacs.7b04011
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发表时间：
2017
影响因子：
15
通讯作者：
Tian Zhong-Qun
中科院分区：
文献类型：
--
作者：
Zhang Hua;Zhang Xia-Guang;Wei Jie;Wang Chen;Chen Shu;Sun Han-Lei;Wang Ya-Hao;Chen Bing-Hui;Yang Zhi-Lin;Wu De-Yin;Li Jian-Feng;Tian Zhong-Qun
深入了解界面结构和性质如何影响催化过程是多相催化中最具挑战性的问题之一。本文采用原位表面增强拉曼光谱（Sers）和壳隔离纳米颗粒增强拉曼光谱（SHINERS）技术，在分子水平上研究了Pt-Au和Pt-氧化物-Au界面对H2活化和对硝基硫酚（pNTP）加氢反应的重要作用.通过合成Pt-on-Au和Pt-on-SHINs纳米复合材料制备了Pt-Au和Pt-oxide-Au界面。直接光谱证据表明，在Pt纳米催化剂上生成的原子氢物种可以通过Pt-Au和Pt-TiO 2-Au界面从Pt溢出到Au，但会在Pt-SiO 2-Au界面被阻挡，导致Pt-on-Au和Pt-on-SHINs纳米复合材料上不同的反应途径和产物选择性。这些发现也得到了密度泛函理论计算的验证。此外，我们还发现组装在无针孔壳层隔离纳米颗粒上的催化剂（Pt-on-pinhole-free-SHINs）可以克服Au核对反应的影响，可以作为多相催化的原位研究平台。这一工作为阐明原位反应的细节提供了一个具体的例子，有助于挖掘界面在催化中的基础作用。
Insightful understanding of how interfacial structures and properties affect catalytic processes is one of the most challenging issues in heterogeneous catalysis. Here, the essential roles of Pt–Au and Pt−oxide−Au interfaces on the activation of H2and the hydrogenation of para-nitrothiophenol (pNTP) were studied at molecular level byin situsurface-enhanced Raman spectroscopy (SERS) and shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). Pt–Au and Pt–oxide–Au interfaces were fabricated through the synthesis of Pt-on-Au and Pt-on-SHINs nanocomposites. Direct spectroscopic evidence demonstrates that the atomic hydrogen species generated on the Pt nanocatalysts can spill over from Pt to Au via the Pt–Au and Pt–TiO2–Au interfaces, but would be blocked at the Pt–SiO2–Au interfaces, leading to the different reaction pathways and product selectivity on Pt-on-Au and Pt-on-SHINs nanocomposites. Such findings have also been verified by the density functional theory calculation. In addition, it is found that nanocatalysts assembled on pinhole-free shell-isolated nanoparticles (Pt-on-pinhole-free-SHINs) can override the influence of the Au core on the reaction and can be applied as promising platforms for thein situstudy of heterogeneous catalysis. This work offers a concrete example of how SERS/SHINERS elucidate details aboutin situreaction and helps to dig out the fundamental role of interfaces in catalysis.