Zhang Jian, Wang Hai, Wang Liang, Ali Sajjad, Wang Chengtao, Wang Lingxiang, Meng Xiangju, Li Bo, Su Dang Sheng, Xiao Feng-Shou
Key Laboratory of Applied Chemistry of Zhejiang Province, Department of Chemistry , Zhejiang University , Hangzhou 310028 , China.
Beijing Advanced Innovation Center for Soft Matter Science and Engineering , Beijing University of Chemical Technology , Beijing 100029 , China.
J Am Chem Soc. 2019 Feb 20;141(7):2975-2983. doi: 10.1021/jacs.8b10864. Epub 2019 Feb 6.
Classical strong metal-support interactions (SMSI), which play a crucial role in the preparation of supported metal nanoparticle catalysts, is one of the most important concepts in heterogeneous catalysis. The conventional wisdom for construction of classical SMSI involves in redox treatments at high-temperatures by molecular oxygen or hydrogen, sometimes causing sintered metal nanoparticles before SMSI formation. Herein, we report that the aforementioned issue can be effectively avoided by a wet-chemistry methodology. As a typical example, we demonstrate a new concept of wet-chemistry SMSI (wcSMSI) that can be constructed on titania-supported Au nanoparticles (Au/TiO-wcSMSI), where the key is to employ a redox interaction between Au and Ti precursors in aqueous solution. The wcSMSI is evidenced by covering Au nanoparticles with the TiO overlayer, electronic interaction between Au and TiO, and suppression of CO adsorption on Au nanoparticles. Owing to the wcSMSI, the Au-TiO interface with an improved redox property is favorable for oxygen activation, accelerating CO oxidation. In addition, the oxide overlayer efficiently stabilizes the Au nanoparticles, achieving sinter-resistant Au/TiO-wcSMSI catalyst in CO oxidation.
经典的强金属-载体相互作用（SMSI）在负载型金属纳米颗粒催化剂的制备中起着关键作用，是多相催化中最重要的概念之一。构建经典SMSI的传统方法涉及通过分子氧或氢气在高温下进行氧化还原处理，这有时会在SMSI形成之前导致金属纳米颗粒烧结。在此，我们报道上述问题可以通过湿化学方法有效避免。作为一个典型例子，我们展示了一种可以在二氧化钛负载的金纳米颗粒（Au/TiO-wcSMSI）上构建的湿化学SMSI（wcSMSI）新概念，其关键在于利用金和钛前驱体在水溶液中的氧化还原相互作用。wcSMSI通过用TiO覆盖层覆盖金纳米颗粒、金与TiO之间的电子相互作用以及抑制CO在金纳米颗粒上的吸附来证明。由于wcSMSI，具有改善的氧化还原性质的Au-TiO界面有利于氧活化，加速CO氧化。此外，氧化物覆盖层有效地稳定了金纳米颗粒，在CO氧化中实现了抗烧结的Au/TiO-wcSMSI催化剂。
