The activity of cadmium oxide as a catalyst for hydrogen dehydrogenation

The Catalytic Mechanics of Dynamic Surfaces: Stimulating Methods for Promoting Catalytic Resonance

“…The most restrictive catalytic limitation is the Sabatier principle, which posits that optimal catalysts exhibit intermediate surface binding energies to balance the kinetic rates of two or more reaction phenomena including surface reactions, desorption, or adsorption . Since it was first proposed by Sabatier that the optimal catalyst forms a “surface complex” that readily forms and desorbs, the principle was demonstrated decades later as kinetic plots referred to as “Sabatier volcanoes” with the optimal catalyst existing at the conditions of peak turnover frequency. − The lower catalytic rate on either side of the volcano derives from the catalyst favoring one elementary step over the others, resulting in lower overall turnover frequency through the whole sequence of steps. This concept has since been demonstrated across a broad range of chemistries and even extended into “volcano surfaces” or “maps” for multicomponent reactions − and dual site catalysts. , …”

“…proposed by Sabatier that the optimal catalyst forms a 'surface complex' that readily forms and desorbs (23) , the principle was demonstrated decades later as kinetic plots referred to as 'Sabatier volcanoes' with the optimal catalyst existing at the conditions of peak turnover frequency (24,25,26) . Lower catalytic rate on either side of the volcano derives from the catalyst favoring one elementary step over the others, resulting in lower overall turnover frequency through the whole sequence of steps.…”

Principles of Dynamic Heterogeneous Catalysis: Surface Resonance and Turnover Frequency Response

“…16,17 Quantitative description of the Sabatier principle was captured in Balandin-Sabatier volcano-shaped curves ("volcano curves" for the remainder of the manuscript), which depicted a metric of catalyst activity relative to a descriptor of substrate binding. 18,19 Balandin depicted volcano-shaped curves in 1960 and 1964 for the dehydration and dehydrogenation of alcohols, with the catalytic activity dependent on the bond energies between the alcohol oxygen and the metal oxide catalysts. 18,19 Since that time, volcano curves have been generated for numerous catalytic chemistries including NO x decomposition, 20 propylene oxidation, 21 hydrodesulfurization, 22,23 ammonia synthesis, 24,25 CO oxidation, 26 and oxygenate decomposition, 27 among many other reactions.…”

“…18,19 Balandin depicted volcano-shaped curves in 1960 and 1964 for the dehydration and dehydrogenation of alcohols, with the catalytic activity dependent on the bond energies between the alcohol oxygen and the metal oxide catalysts. 18,19 Since that time, volcano curves have been generated for numerous catalytic chemistries including NO x decomposition, 20 propylene oxidation, 21 hydrodesulfurization, 22,23 ammonia synthesis, 24,25 CO oxidation, 26 and oxygenate decomposition, 27 among many other reactions. 28 The simplest surface catalytic mechanism of species A reacting to species B depicted in Figure 1A the surface as A*, undergoes surface reaction to B*, and then desorbs to gas-phase product B; the overall turnover rate can potentially be limited by any one of these three steps.…”

“…Catalytic rate enhancement occurs primarily through catalyst design to tune the binding characteristics of surface species and transition states for maximum catalytic turnover frequency. − In the past two decades, advances in nanostructured materials led to detailed synthesis of atomic-scale active sites that precisely balance the surface substrate binding energies . The limit of this approach is characterized by the Sabatier principle, which states that the binding of substrates must be neither too strong nor too weak. , Quantitative description of the Sabatier principle was captured in Balandin-Sabatier volcano-shaped curves (“volcano curves” for the remainder of the manuscript), which depicted a metric of catalyst activity relative to a descriptor of substrate binding. , Balandin depicted volcano-shaped curves in 1960 and 1964 for the dehydration and dehydrogenation of alcohols, with the catalytic activity dependent on the bond energies between the alcohol oxygen and the metal oxide catalysts. , Since that time, volcano curves have been generated for numerous catalytic chemistries including NO x decomposition, propylene oxidation, hydrodesulfurization, , ammonia synthesis, , CO oxidation, and oxygenate decomposition, among many other reactions …”