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Volcano curves have proven to be particularly useful in new catalyst design in the field of heterogeneous catalysis. On the other hand, the further enhancement of the performance of the optimal cat...

The catalytic dehydrogenation of light alkanes over Pt catalysts is generally accepted to follow a reverse Horiuti–Polanyi mechanism. Using a microkinetic analysis in combination with results from ...

The structure–performance relationship is a critical fundamental issue in heterogeneous catalysis, and the size-dependent structure sensitivity of catalytic reactions has long been researched in ca...

Highly dispersed bimetallic Pd-In catalysts on Al2O3 were prepared by a simple impregnation method. In comparison with the unsupported intermetallic catalyst, the supported Pd-In catalyst exhibited several magnitudes higher activity and similar selectivity for selective acetylene hydrogenation. Moreover, the activity, selectivity, and anticoking performance of the Pd-In catalyst were superior to those of the monometallic Pd catalyst. The electron transferred from indium weakened the adsorption of ethylene on the negatively charged Pd sites and hence improved the selectivity of Pd-In/Al2O3. The inhibited formation of hydride due to the presence of indium also contributed to the higher selectivity. The promoted activation of hydrogen, owing to the weak adsorption of acetylene on Pd-In/Al2O3, and decreased particle size jointly contributed to the enhanced activity of Pd-In/Al2O3. In addition, green oil formation on Pd-In/Al2O3 was retarded by the presence of indium, contributing to the enhanced stability of ...

Platinum cluster size has a significant influence on the activity, selectivity, and stability as well as the reaction mechanism during propane dehydrogenation (PDH). Well-controlled platinum catalysts of different cluster sizes are prepared by a seed growth method and supported on calcined hydrotalcite. The Pt catalysts show strong structure-sensitive behavior both in the C–H bond activation of propane and in the C–C bond activation to yield ethylene, methane, and coke. The Pt clusters of small cluster sizes, with (211) dominating on the surface, have a lower dehydrogenation energy barrier and thus higher activity. However, large Pt clusters with Pt(111) dominating result in a weakened binding strength of propylene and an increased energy barrier for the activation of C–H bonds in propylene, which leads to higher selectivity toward propylene by lowering the possibility of deep dehydrogenation. Kinetic analysis illustrates that the reaction order in hydrogen decreases and activation energy increases with a...

Density functional theory calculations have been performed to investigate the effect of Sn on the catalytic activity and selectivity of Pt catalyst in propane dehydrogenation. Five models with different Sn to Pt surface molar ratios are constructed to represent the PtSn surfaces. With the increase of the Sn content, the d-band of Pt is broadened, which gives rise to a downshift in the d-band center on the PtSn surfaces. Consequently, the bonding strength of propyl and propylene on the alloyed surfaces is lowered. With the decomposition of the adsorption energy, the change in the surface deformation energy is predicted to be the dominant factor that determines the variation in the adsorption energy on the surface alloys, while on the bulk alloys the change in the binding energy makes a major contribution. The introduction of Sn lowers the energy barrier for propylene desorption and simultaneously increases the activation energy for propylene dehydrogenation, which has a positive effect on the selectivity t...