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[Display omitted] • Non-precious intermetallic compound catalysts for propane dehydrogenation. • Scaling relations are established using formation energies over terraces and steps. • Descriptor-based microkinetic analysis is carried out to obtain volcano curves. • Fe 3 Ga 1 is a good catalyst candidate with improved catalytic performance. By using a descriptor-based microkinetic analysis combined with results from density functional theory calculations over eight transition-metal (including Ni, Cu, Rh, Pd, Ag, Ir, Pt, and Au) terrace and stepped surfaces, intermetallic compounds have been screened to search for inexpensive and environmentally friendly propane dehydrogenation (PDH) catalysts with enhanced catalytic performance. Based on the scaling relations, the formation energies of ethyl on terrace and methylidyne on stepped surfaces are identified as two descriptors to represent the energetics of other reaction intermediates and transition sates. The derived PDH activity and propylene selectivity volcano curves not only provide a rational interpretation of the previously experimentally reported catalyst candidates, but also predict several unexpected binary combinations by screening 1482 A 3 B 1 and 741 A 1 B 1 intermetallic compounds. The non-precious Fe 3 Ga 1 is then synthesized and evaluated. Its improved propylene selectivity and catalytic stability with respect to those of the Pt catalyst validates the theoretical predictions experimentally. [ABSTRACT FROM AUTHOR]

[Display omitted] • Substitution of transition metals for Cr increases the acidity of the adjacent O. • Linear scaling relations are established to identify the PDH activity descriptor. • High propylene selectivity of the M 1 -Cr 2 O 3 catalysts is achieved. • Cu 1 -Cr 2 O 3 is predicted to be the best catalyst for PDH among the 13 doped Cr 2 O 3. The catalytic behavior of M 1 -Cr 2 O 3 (M = Mn-Cu, Ru-Ag, and Os-Au) in propane dehydrogenation (PDH) has been studied by employing microkinetic modeling combined with results from periodic DFT + U calculations. Calculated results indicate that most of the single atoms concerned can be stably present on the Cr 2 O 3 surface. The adsorption energy calculations and Bader charge analysis demonstrate that the acidity of the O sites adjacent to the M sites would be enhanced upon doping, which in turn strengthens the atomic H adsorption and the co-adsorption of various PDH species. The surface H formation energy is identified as the reactivity descriptor for PDH over the M 1 -Cr 2 O 3 catalysts, and a volcano curve of the PDH activity is obtained. By calculating the difference between the propylene dehydrogenation and desorption barriers, it is found that some M 1 -Cr 2 O 3 catalysts show improved selectivity towards propylene, as compared to Cr 2 O 3. Comparison between the formation barriers of H 2 and H 2 O reveals that single-atom doping has no apparent negative effect on the catalytic stability of the Cr 2 O 3 surface. The Cu 1 -Cr 2 O 3 catalyst is finally identified as the most promising catalyst for PDH among the 13 M 1 -Cr 2 O 3 catalyst candidates, considering the catalytic activity, selectivity, stability, and cost. [ABSTRACT FROM AUTHOR]