MXene-Supported Pt Catalysts for Methylcyclohexane Dehydrogenation: Activity, Stability and Pathway Regulation

Herein, a series of few layer MXene (Ti3C2Tx, Ti3CNTx, Ti2NTx, Ti2CTx, Cr2CTx, Nb2CTx, and V2CTx) are synthesized via a LiF/HCl etching-exfoliation method and employed as supports for Pt catalysts in fixed-bed methylcyclohexane (MCH) dehydrogenation reactions. The Pt/MXene catalysts exhibit strong support-dependent dehydrogenation activity and stability. Notably, Pt/Ti3C2Tx shows the highest and most stable hydrogen evolution performance over the studied temperature range, while Pt/Nb2CTx deactivates due to carbon deposition at moderate to high temperatures. X-ray photoelectron spectroscopy analysis reveals that MXene supports effectively modulate the Pt0/Pt2+/Pt4+ distribution, indicating unique metal–support electronic interactions. Further analysis using gas chromatography–mass spectrometry identifies olefin intermediates generated in the reaction, showing that interfacial chemical differences among MXene supports influence the reactant adsorption configuration, initial dehydrogenation sites, and intermediate isomerization behavior. Overall, this study elucidates how MXene supports regulate Pt sites and MCH dehydrogenation pathways, providing valuable insights for the design of efficient LOHC catalysts.