Cu-Ce Dual-Atom Sites Embedded in Zeolites Boost Resistance to Impurity Interference for Environmental Catalysis

Area of Science:

• Catalysis
• Materials Science
• Environmental Science

Background:

• Biodiesel use leads to phosphorus and metal cation contamination in exhaust.
• This contamination deactivates conventional Cu-SSZ-13 catalysts for NO_X reduction.
• Catalyst deactivation occurs via pore blockage, framework degradation, and copper site loss.

Purpose of the Study:

• To develop a robust catalyst resistant to phosphorus poisoning for ammonia-selective catalytic reduction (NH₃-SCR).
• To investigate the role of cerium (Ce) in enhancing catalyst stability and performance under phosphorus-rich conditions.
• To provide a practical strategy for durable catalysts in impurity-sensitive environmental applications.

Main Methods:

• Synthesis of a Cu-Ce dual-atom catalyst embedded in the SSZ-13 zeolite framework.
• Characterization of catalyst structure, including the precise positioning of Ce species.
• Evaluation of catalyst performance in NH₃-SCR under simulated phosphorus-rich exhaust conditions.

Main Results:

• The Cu-Ce dual-atom catalyst demonstrated high NO_X conversion (90%) and N₂ selectivity (100%) at 210 °C, even after phosphorus exposure.
• Ce species in the eight-membered rings displaced P-sensitive sites, favoring P-tolerant Z₂Cu²⁺ species in six-membered rings.
• Ce-P interactions restored the electronic environment of Cu sites, improving NH₃/NO adsorption and redox cycling.

Conclusions:

• The developed Cu-Ce dual-atom catalyst offers excellent resistance to phosphorus poisoning in NH₃-SCR.
• This catalytic design presents a viable pathway for durable, impurity-tolerant catalysts in sustainable mobility.
• The strategy is applicable to other environmental reactions like NH₃ oxidation and NO_X with VOCs removal.