posted on 2022-12-19, 18:08authored byJiayi Wang, Haoxiang Xu, Chunxia Che, Jiqin Zhu, Daojian Cheng
Pd-based catalysts are widely used in selective hydrogenation
reactions,
where the surface structure has been found as a key factor to improve
the yield of the target product. However, little study is involved
in a prediction model for rationally engineering the surface structure
of Pd-based catalysts with their catalytic properties. Here, using
PdAg bimetal catalyzed acetylene selective hydrogenation as a probe
reaction, we combined density functional theory calculations and microkinetic
models and then revealed structure–performance relationships
for PdAg bimetal based on structure descriptors, which qualitatively
reflect the ligand effect and stress effect on the adsorption of reactants.
The descriptor-based screening strategy allows us to rationally engineer
the surface status (element composition and atomic arrangement) of
PdAg bimetals and identify candidates with an optimized yield of ethylene
product, namely, Pd1Ag3 alloy, which is further
confirmed by available references and our catalysis experiments. This
screening strategy based on structure descriptors may be generalized
for rationally designing the surface structure of Pd-based catalysts
for other hydrogenation reactions beyond acetylene selective hydrogenation.