Zinc-assisted nanometric Pt cluster stabilized on KL zeolite via atomic layer deposition for the n-heptane aromatization

Nanometric Pt clusters show promising applications in alkane reforming. However, stabilizing the nanometric Pt clusters on the zeolite at high temperature is still challenging. Herein, we fabricate the zinc-assisted nanometric Pt cluster stabilized on the KL zeolite using atomic layer deposition technology. The deposition of Zn significantly enhances the stability of nanometric Pt cluster and, therefore, makes PtZn3/KL as a robust n-heptane dehydrocyclization catalyst. Systematic characterizations combined with DFT calculations disclose that the deposited Zn species donate electrons to Pt and thus promote the cleavage of C-H bond of n-heptane and facilitate the dehydrocyclization of alkene-like intermediates (σC7=) to aromatics. In addition, an easier desorption of toluene benefits the high reactivity of PtZn3/KL catalyst by preventing the dehydrogenation and cleavage of C-C bonds to form the by-products or coke deposition. This method for enhancing the stability of nanometric Pt clusters paves a way for designing high-efficient dehydrocyclization catalysts.