3 research outputs found
Surface Diffusion Barriers and Catalytic Activity Driven by Terminal Groups at Zeolite Catalysts
Defects that commonly exist on the surface of zeolites
pose notable
mass transport constraints and influence the catalytic performance.
The mechanism underlying the surface defects inducing molecular transport
limitations, however, is not fully understood. Herein, we use versatile
spectroscopy, imaging techniques, and multiscale simulations to investigate
the effect of surface defects on the molecular surface transport in
zeolites, intending to establish the terminal structure–mass
transport–performance relationship. Isolated silanol, which
represents the foremost and eventual chemical defective accessible
site at zeolite termination for guest molecules from the bulk fluid
phase into zeolites or vice versa, is taken as a showcase. We demonstrate
that isolated silanol at H-SAPO-34 zeolite termination not only enhances
the adsorptive interaction between the polar molecules/alkenes and
interface but also narrows the local 8-membered-ring pore at the external
surface. The exterior surface with more isolated silanol could cause
a higher diffusion barrier and hamper the accessibility of intracrystalline
active sites. This work is expected to shed light on the mechanism
underlying the zeolite catalyst upgrading via terminal surface modifications
at zeolites
Surface Diffusion Barriers and Catalytic Activity Driven by Terminal Groups at Zeolite Catalysts
Defects that commonly exist on the surface of zeolites
pose notable
mass transport constraints and influence the catalytic performance.
The mechanism underlying the surface defects inducing molecular transport
limitations, however, is not fully understood. Herein, we use versatile
spectroscopy, imaging techniques, and multiscale simulations to investigate
the effect of surface defects on the molecular surface transport in
zeolites, intending to establish the terminal structure–mass
transport–performance relationship. Isolated silanol, which
represents the foremost and eventual chemical defective accessible
site at zeolite termination for guest molecules from the bulk fluid
phase into zeolites or vice versa, is taken as a showcase. We demonstrate
that isolated silanol at H-SAPO-34 zeolite termination not only enhances
the adsorptive interaction between the polar molecules/alkenes and
interface but also narrows the local 8-membered-ring pore at the external
surface. The exterior surface with more isolated silanol could cause
a higher diffusion barrier and hamper the accessibility of intracrystalline
active sites. This work is expected to shed light on the mechanism
underlying the zeolite catalyst upgrading via terminal surface modifications
at zeolites
Surface Diffusion Barriers and Catalytic Activity Driven by Terminal Groups at Zeolite Catalysts
Defects that commonly exist on the surface of zeolites
pose notable
mass transport constraints and influence the catalytic performance.
The mechanism underlying the surface defects inducing molecular transport
limitations, however, is not fully understood. Herein, we use versatile
spectroscopy, imaging techniques, and multiscale simulations to investigate
the effect of surface defects on the molecular surface transport in
zeolites, intending to establish the terminal structure–mass
transport–performance relationship. Isolated silanol, which
represents the foremost and eventual chemical defective accessible
site at zeolite termination for guest molecules from the bulk fluid
phase into zeolites or vice versa, is taken as a showcase. We demonstrate
that isolated silanol at H-SAPO-34 zeolite termination not only enhances
the adsorptive interaction between the polar molecules/alkenes and
interface but also narrows the local 8-membered-ring pore at the external
surface. The exterior surface with more isolated silanol could cause
a higher diffusion barrier and hamper the accessibility of intracrystalline
active sites. This work is expected to shed light on the mechanism
underlying the zeolite catalyst upgrading via terminal surface modifications
at zeolites