Catalytic resonance theory: parallel reaction pathway control

Abstract

Branched catalytic reaction networks with oscillating chemical pathways perfectly select for reaction products at varying frequency.

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

“…Although not shown here, sampling of a wider range of both chemical and dynamic catalyst parameters indicates significant potential for controlling the selectivity to products for a wide range of catalytic chemistries. (51)…”

“…As shown in Figure 17a, comparison of the periodic trends for the adsorption of NH 2 * and NH* with the application of electric fields on Pt (111) surface both indicate positive scaling of NH2 * /NH * of 0.49 and 1.37, respectively. (51,276,(312)(313)(314)(315)(316)(317) The divergence of the two linear relations indicates the potential for breaking periodic linear scaling relationships. In addition, the linear relationships (i.e., gamma parameters) are likely to be metaldependent for the same external stimulus, as shown for distinct CH2O2 * * /CH3OH * on Ni (111) and Pt (111) surface (Figure 17b).…”

“…It has already been experimentally demonstrated that oscillating catalysts break the limits of static catalysts in the rate acceleration of electro-oxidation of formic acid (50) . But it is also possible that dynamic catalysts can change the mechanism for selecting individual reactions in a network (51) , while also altering catalyst operation in equilibrium-controlled reactions (52) . Dynamic catalysts are common materials with physical design parameters including composition (e.g., metals, metal oxides), size, and structure, but they also have new dynamic parameters including surface oscillation frequency, amplitude, and applied waveform shape (e.g.…”

“…Simulation of parallel reaction systems (catalytic conversion of chemical A via parallel pathways to products B and C) with a broad range of chemical parameters (adsorbate linear scaling parameters γ and δ, and Brønsted Evans Polanyi parameters α and β) revealed that parallel chemistries can be highly tuned towards selectivity between either product through the manipulation of oscillation parameters (amplitude and frequency). (51) As shown in the example with opposite gamma values between parallel reactions (γ B/A ~ 2.0, γ C/A ~ 0.5) in the Sabatier volcano plots of Figure 6a, static catalysts either select for product C or a 50/50% ratio of B and C; no condition exists for selective production solely of B. However, oscillation of the binding energy of A* at varying amplitude and frequency centered at -0.2 eV relative binding energy of A* reveals complex reaction behavior.…”

Coverage-dependent formic acid oxidation reaction kinetics determined by oscillating potentials

“…It was further predicted that oscillations need to be in approximate resonance with the surface reactions to achieve reaction enhancements. [9][10][11][12] DFT calculations by Shetty et al revealed electric field-dependent linear scaling relationships of adsorbates on metal surfaces imperative for the understanding of dynamic catalytic processes. 13 Cycling between a potential suitable for the non-Faradaic dehydration of FA to surfaceadsorbed CO and the Faradaic oxidative desorption to form CO 2 enhanced the activity by a factor of up to around 20 at frequencies of 100 Hz, 14 consistent with promotional effect observed by Adžić et al earlier.…”