With natural gas becoming a plentiful resource and CO2 impacting climate, developing methane dry reforming catalysts that operate at lower temperatures (T&lt;600oC) with more ideal product distributions (1:1 H2:CO) is of significant interest. Methane dry reforming exhibits many challenges that include recalcitrant C-H bond activation, unbalanced dehydrogenation and carbon oxidation kinetics that lead to coke formation, and unselective O/OH hydrogenation that leads to H2O formation. Common late transition metal (TM) and TM+TM alloys often suffer from coke deposition due to the imbalance of carbon and oxygen supply and rapid O/OH hydrogenation, which results in coke formation and the need for significantly elevated temperatures to reduce H2O formation. On the other hand, ideal catalyst surface chemistry would enable C-H activation and oxidation of CHx/C for CO production at lower temperature while simultaneously controlling the fate of atomic H to limit the hydrogenation of O/OH to form H2O and promote H2 formation. Intermetallic compounds (IMCs) have been found to present a new spectrum of surface chemistry towards C, O, and H that may be appropriate for dry reforming catalyst design. This study focuses on understanding the catalytic surface chemistry of IMCs using DFT surface reaction modeling, Kinetic Monte Carlo simulations, and experimental investigations to produce a clear pathway forward for catalyst design. Our studies have isolated regions of the IMC compositional space that may simultaneously provide for CH4 activation, efficient oxidation kinetics, and limited H2O formation. IMCs have illustrated greater control over the hydrogenation kinetics that promote more ideal H2:CO ratios due improved electronic hybridization between the TM and p-block elements. Additionally, electronegativity of parent elements play a critical role in O/OH stability and hydrogenation kinetics for H2O formation.

Limiting unselective H2O formation in the dry-reforming of CH4 using elevated oxophilicity and limited hydrogenation kinetics of intermetallic compounds composed of non-noble transition metals and p-block elements

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