Sustainable synthesis of bimetallic single atom gold-based catalysts with enhanced durability in acetylene hydrochlorination
Abstract
Gold single‐atom catalysts (SACs) exhibit outstanding reactivity in acetylene hydrochlorination to vinyl chloride, but their practical applicability is compromised by current synthesis protocols, using aqua regia as chlorine‐based dispersing agent, and their high susceptibility to sintering on non‐functionalized carbon supports at >500 K and/or under reaction conditions. Herein, a sustainable synthesis route to carbon‐supported gold nanostructures in bimetallic catalysts is developed by employing salts as alternative chlorine source, allowing for tailored gold dispersion, ultimately reaching atomic level when using H2PtCl6. To rationalize these observations, several synthesis parameters (i.e., pH, Cl‐content) as well as the choice of metal chlorides are evaluated, hinting at the key role of platinum in promoting a chlorine‐mediated dispersion mechanism. This can be further extrapolated to redisperse large gold agglomerates (>70 nm) on carbon carriers into isolated atoms, which has important implications for catalyst regeneration. Another key role of platinum single atoms is to inhibit the sintering of their spatially isolated gold‐based analogs up to 800 K and during acetylene hydrochlorination, without compromising the intrinsic activity of Au(I)‐Cl active sites. Accordingly, exploiting cooperativity effects of a second metal is a promising strategy towards practical applicability of gold SACs, opening up exciting opportunities for multifunctional single‐atom catalysis. Show more
Publication status
publishedExternal links
Journal / series
SmallVolume
Pages / Article No.
Publisher
WileySubject
acetylene hydrochlorination; bimetallic catalysts; gold; platinum; single‐atom catalysisOrganisational unit
03871 - Pérez-Ramírez, Javier / Pérez-Ramírez, Javier
Funding
ETH-40 17-1 - Design of acetylene hydrochlorination catalysts for sustainable PVC production (ETHZ)
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