The Active Site of Methanol Synthesis over Cu/ZnO/Al2O3 Industrial Catalysts

TLDR: This work shows how to identify the crucial atomic structure motif for the industrial Cu/ZnO/Al2O3 methanol synthesis catalyst by using a combination of experimental evidence from bulk, surface-sensitive, and imaging methods collected on real high-performance catalytic systems in combination with density functional theory calculations.

Abstract: Unlike homogeneous catalysts, heterogeneous catalysts that have been optimized through decades are typically so complex and hard to characterize that the nature of the catalytically active site is not known. This is one of the main stumbling blocks in developing rational catalyst design strategies in heterogeneous catalysis. We show here how to identify the crucial atomic structure motif for the industrial Cu/ZnO/Al{sub 2}O{sub 3} methanol synthesis catalyst. Using a combination of experimental evidence from bulk-, surface-sensitive and imaging methods collected on real high-performance catalytic systems in combination with DFT calculations. We show that the active site consists of Cu steps peppered with Zn atoms, all stabilized by a series of well defined bulk defects and surface species that need jointly to be present for the system to work.

Full text

Methanol)Synthesis)over)Cu/ZnO/Al
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Unlike)homogeneous)catalysts,)heterogeneous)catalysts)that)have)been)optimized)through)
decades)are)typically)so)complex)and)hard)to)characterize)that)the)nature)of)the)catalytically)active)
site)is)not)known.)This)is)one)of)the)main)stumbling)blocks)in)developing)rational)catalyst)design)
strategies)in)heterogeneous)catalysis.)We)show )here)how )to)identify)the)crucial)atomic)structure)
motif)for)the)industrial)Cu/ZnO/Al
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performance)catalytic)systems)in)combination)with)DFT)calculations.)We)show)that)the)active)site)
consists)of)Cu)steps)peppered)with)Zn)atoms,)a ll)s ta b iliz e d )b y)a )s e rie s )o f)well)defin e d )b u lk)d e f e ct s)
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SLAC-PUB-14662
Work supported in part by US Department of Energy contract DE-AC02-76SF00515.
Submitted to Science

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Frequently asked questions

Q1. What are the contributions in this paper?

The authors show here how to identify the crucial atomic structure motif for the industrial Cu/ZnO/Al2O3 methanol synthesis catalyst. The authors show that the active site consists of Cu steps peppered with Zn atoms, all stabilized by a series of well defined bulk defects and surface species that need jointly to be present for the system to work.