Noble metals play a momentous role in heterogeneous catalysis but still face a huge challenge in selectivity control. Herein, we report isolating contiguous Pt atoms and forming Pt-Zn intermetallic nanoparticles as an effective strategy to optimize the selectivity of Pt catalysts. Contiguous Pt atoms are isolated into single atoms and Pt-Zn intermetallic nanoparticles are formed which are supported on hollow nitrogen-doped carbon nanotubes (PtZn/HNCNT), as confirmed by aberration-corrected high-resolution transmission electron microscopy and X-ray absorption spectrometry measurements. Interestingly, this PtZn/HNCNT catalyst promotes the hydrogenation of 4-nitrophenylacetylene to 4-aminophenylacetylene with a much higher conversion ( > 99%) and selectivity (99%) than the comparison samples with Pt isolated-single-atomic-sites (Pt/HNCNT) and Pt nanoparticles (Pt/CN). Further density functional theory (DFT) calculations disclose that the positive Zn atoms assist the adsorption of nitro group and Pt-Zn intermetallic nanoparticles facilitate the hydrogenation on nitro group kinetically.

贵金属在非均相催化中起着举足轻重的作用，但在选择性控制方面仍面临巨大挑战。在本文中，我们报道了隔离连续的Pt原子并形成Pt-Zn金属间纳米颗粒作为优化Pt催化剂选择性的有效策略。通过像差校正的高分辨率透射电子显微镜和X射线吸收光谱法证实，连续的Pt原子被分离成单个原子，并形成了Pt-Zn金属间纳米颗粒，该纳米颗粒被负载在中空氮掺杂的碳纳米管（PtZn / HNCNT）上。测量。有趣的是，这种PtZn / HNCNT催化剂以更高的转化率（>> 与Pt分离的单原子位点（Pt / HNCNT）和Pt纳米颗粒（Pt / CN）的比较样品相比，分离度为99％，选择性为99％。进一步的密度泛函理论（DFT）计算表明，正的Zn原子有助于硝基的吸附，而Pt-Zn金属间化合物纳米粒子在动力学上促进了在硝基上的氢化。