Catalytic Performance of Highly Dispersed Bimetallic Catalysts for CO Hydrogenation to DME

TL;DR

This paper explores the synthesis and performance of bimetallic catalysts for converting CO to DME, with Cu-Zn showing the best results.

Contribution

A new synthesis method using pyrolysis of metal-doped ZIF precursors to create highly dispersed bimetallic catalysts.

Findings

Cu-Zn-NC catalyst achieved 32.8% CO conversion and 95.2% DME selectivity.

Incorporating Cu preserved the Zn-N structure and catalytic performance.

Bimetallic components showed synergistic effects enhancing catalytic activity.

Abstract

Highly dispersed bimetallic atomic‐scale catalysts have garnered significant attention in syngas conversion filed due to the synergistic effects of the precisely structured bimetallic site, which facilitate the effective activation of CO. Despite their potential, synthesizing these catalysts to meet the specific application requirements remains challenging. Herein, various bimetallic catalysts were synthesized through the pyrolysis of the bimetallic ZIF precursors which were prepared by in situ doping of different metals (Mn, Fe, Co, Ni and Cu) into the ZIF‐8 structure. In the presence of a highly dispersed and highly loaded Zn, the doping content in the ultimate second metallic catalysts varied between 0.15–1.20 wt % for different metals. The catalysts were systematically characterized using XRD, BET, TEM, XPS, Raman, ICP, and H2‐TPD techniques. Among them, the Zn−NC regulated with Cu or Ni exhibited superior catalytic performance. Notably, the Cu−Zn−NC catalyst showed the highest activity, achieving a CO conversion of 32.8 % and optimal DME selectivity approaching 95.2 % in CO hydrogenation reactions. These enhanced performance metrics were attributed to the synergetic effects of bimetallic components. The incorporation of Cu not only preserved the original Zn−N structure but also preserved the catalytic performance unchanged. This preparation strategy is expected to filter out new research targets to use in diverse catalytic applications.

To enhance the catalytic performance of Zn−NC in the hydrogenation of CO to dimethyl ether, highly dispersed bimetallic catalysts are synthesized through the pyrolysis different metal‐doped ZIF. The incorporation of secondary metals (Mn, Fe, Co, Ni, Cu) leads to distinct variations in catalytic performance. Among them, the introduction of Cu significantly improves catalytic activity.

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