Ligand-tuned PtO single-atom catalysts for efficient acetylene hydrochlorination

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• Platinum single-atom catalysts (SACs) show promise but often lack sufficient activity for industrial applications like acetylene hydrochlorination.
• Mercury-based catalysts are currently used but pose environmental concerns.

Purpose of the Study:

• To develop a highly active and stable platinum single-atom catalyst for acetylene hydrochlorination.
• To address the limitations of current catalysts by employing a novel coordination strategy.

Main Methods:

• Fabrication of a Pt single-atom catalyst on spherical activated carbon using 4-methoxyphenylacetic acid (L2) as a ligand (Pt-L2/SAC).
• Evaluation of catalytic performance under specific conditions (200 °C, GHSV(C2H2) = 50 h⁻¹).
• Utilized characterization techniques and density functional theory (DFT) calculations to understand the catalyst's mechanism.

Main Results:

• Pt-L2/SAC achieved an initial acetylene conversion of 99.63% with a low deactivation rate of 0.01% h⁻¹.
• The L2 ligand effectively anchored Pt atoms via strong Pt-O bonds, ensuring atomic dispersion and stability.
• DFT calculations confirmed that the ligand modulated Pt's electronic structure, alleviating the rate-determining step.

Conclusions:

• The developed Pt-L2/SAC catalyst demonstrates superior activity and stability for acetylene hydrochlorination.
• The coordination strategy using oxygen-containing ligands is effective for designing advanced single-atom catalysts.
• This work offers a potential alternative to mercury-based catalysts in this important industrial process.