Methane dehydroaromatization (MDA, 6 CH₄ → C₆H₆ + 9 H₂) represents a direct route for converting methane into value-added products such as benzene and hydrogen without co-feeds or oxidants. The process offers a promising pathway for distributed valorization of stranded shale gas, enabling modular on-site conversion that mitigates transportation and flaring challenges. Zeolite-supported molybdenum catalysts (Mo/ZSM-5) remain the benchmark systems for this reaction; however, their commercialization is hindered by rapid deactivation and limited control over the active site formation.

Our group has conducted a systematic investigation aimed at uncovering structure–function relationships that govern activity and stability in MDA catalysts. We have shown that the activation protocol used to form Mo carbide species from their oxidic precursors is a decisive factor in achieving long-term catalyst stability. Through in situ/operando X-ray absorption spectroscopy and complementary ex situ characterizations, we have found that the local environment of Mo in the as-prepared state plays a secondary role compared to the conditions under which carburization occurs.

Building upon these insights, we have explored the effects of secondary transition-metal promoters (X = Fe, Co, Ni) and the spatial distribution of active sites within the zeolite. We have employed controlled synthesis strategies to confine or exclude metals from the zeolite channels and external surface. Our findings reveal that promoter effects and the extent of Mo–X synergy depend critically on the relative location and proximity of metal and acid sites: internal sites favor stable benzene formation, while external sites accelerate coke formation. Additional surface modifications through silanation and selective metal extraction confirmed that external Brønsted acid sites are more detrimental than external Mo species, as they predominantly promote oligomerization and coke formation.

Altogether, these studies provide new mechanistic understanding of how metal–acid interactions and the spatial arrangement of active sites within zeolite frameworks govern MDA performance. They also establish rational design principles for tuning metal location and activation chemistry to enhance the durability and selectivity of zeolite-based catalysts for methane valorization.