Scholarlink

<p>Achieving high selectivity toward dihydroxyacetone (DHA) in the base-free oxidation of glycerol is difficult, as it requires preferential activation of the intrinsically less reactive secondary hydroxyl group. To address this, well-defined ordered intermetallic compounds (IMCs) with distinct phases were constructed. Two PtSb IMCs, Pt<sub>1</sub>Sb<sub>1</sub>/CNT and Pt<sub>1</sub>Sb<sub>2</sub>/CNT, were synthesized via an impregnation-reduction method using carbon nanotubes (CNT) as supports. The Pt<sub>1</sub>Sb<sub>1</sub>/CNT catalyst demonstrated superior activity (79.9% conversion) and DHA selectivity (61.1%) compared to Pt<sub>1</sub>Sb<sub>2</sub>/CNT (70.1%, 55.8%), alongside enhanced durability. More importantly, Pt<sub>1</sub>Sb<sub>1</sub>/CNT delivers a markedly higher intrinsic activity, with a turnover frequency (TOF) of 299&#xa0;h<sup>−1</sup>, over twice that of Pt<sub>1</sub>Sb<sub>2</sub>/CNT (144&#xa0;h<sup>−1</sup>). This performance superiority is attributed to its finer nanoparticle size, more electron-deficient Pt surfaces, and robust structural integrity. Density functional theory (DFT) calculations unveiled that the C–H bond cleavage is the rate-determining step and identified a strikingly lower energy barrier for secondary C–H activation on the Pt<sub>1</sub>Sb<sub>1</sub>(100) surface (0.68&#xa0;eV) than on Pt<sub>1</sub>Sb<sub>2</sub>(210) (0.95&#xa0;eV), which conclusively explains the phase-dependent selectivity. This work underscores the critical role of intermetallic phase selection in designing high-performance catalysts for biomass valorization via precise geometric and electronic engineering.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Structural Dependency in Base-Free Glycerol Oxidation over Ordered PtSb Intermetallics for Selective Dihydroxyacetone Production

  • 期刊论文

  • 发表日期：

    2025年12月6日

查看全文
  • Junyan Fang,
  • Wenyao Chen,
  • Yueqiang Cao,
  • Jing Zhang,
  • Xuezhi Duan,
  • Gang Qian,
  • Xinggui Zhou

摘要

Achieving high selectivity toward dihydroxyacetone (DHA) in the base-free oxidation of glycerol is difficult, as it requires preferential activation of the intrinsically less reactive secondary hydroxyl group. To address this, well-defined ordered intermetallic compounds (IMCs) with distinct phases were constructed. Two PtSb IMCs, Pt1Sb1/CNT and Pt1Sb2/CNT, were synthesized via an impregnation-reduction method using carbon nanotubes (CNT) as supports. The Pt1Sb1/CNT catalyst demonstrated superior activity (79.9% conversion) and DHA selectivity (61.1%) compared to Pt1Sb2/CNT (70.1%, 55.8%), alongside enhanced durability. More importantly, Pt1Sb1/CNT delivers a markedly higher intrinsic activity, with a turnover frequency (TOF) of 299 h−1, over twice that of Pt1Sb2/CNT (144 h−1). This performance superiority is attributed to its finer nanoparticle size, more electron-deficient Pt surfaces, and robust structural integrity. Density functional theory (DFT) calculations unveiled that the C–H bond cleavage is the rate-determining step and identified a strikingly lower energy barrier for secondary C–H activation on the Pt1Sb1(100) surface (0.68 eV) than on Pt1Sb2(210) (0.95 eV), which conclusively explains the phase-dependent selectivity. This work underscores the critical role of intermetallic phase selection in designing high-performance catalysts for biomass valorization via precise geometric and electronic engineering.