Non-oxidative coupling of methane via selective passivized catalysis

Area of Science:

• Catalysis science and reaction engineering
• Surface chemistry
• Materials science

Background:

• Methane activation is a critical challenge in catalysis.
• Catalyst activity, selectivity, and stability must be balanced.
• Methane's C-H bond dissociation enthalpy is an inadequate metric for catalytic reactivity.

Purpose of the Study:

• To clarify methane's catalytic reactivity metrics.
• To identify deactivation pathways in non-oxidative coupling of methane (NOCM).
• To introduce selective passivized catalysis (SPC) as a catalyst design strategy.

Main Methods:

• Thermodynamic analysis of NOCM.
• Kinetic studies on Pt-based catalysts.
• Catalyst design via ex situ and in situ passivation techniques.

Main Results:

• Rapid deactivation via deep dehydrogenation and coking limits catalytic performance.
• Selective passivized catalysis (SPC) reconciles activity with stability.
• Sustained NOCM performance with >90% C2 selectivity achieved using Pt-Bi/ZSM-5 and Pt nanolayers on Mo2TiC2Tx MXene.

Conclusions:

• Selective passivized catalysis (SPC) offers a rational blueprint for stabilizing methane activation.
• SPC suppresses undesired pathways while preserving sites for desired products.
• This approach advances non-oxidative coupling of methane (NOCM) toward practical relevance.