Catalytic resonance theory: superVolcanoes, catalytic molecular pumps, and oscillatory steady state

Abstract

Catalytic reactions on surfaces with forced oscillations in physical or electronic properties undergo controlled acceleration consistent with the selected parameters of frequency, amplitude, and external stimulus waveform. In this work, the general reaction of reversible A-to-B chemistry is simulated by varying the catalytic (heat of reaction, transition state and intermediate energies) and oscillation parameters (frequency, amplitude, endpoints, and waveform) to evaluate the influence on the overall catalytic turnover frequency and steady state extent of conversion. Variations of catalytic cycle energies are shown to comprise a superVolcano of superimposed individual Balandin–Sabatier volcano plots, with variations in linear scaling relationships leading to unique turnover frequency response to forced oscillation of the catalyst surface. Optimization of catalytic conditions identified a band of forced oscillation frequencies leading to resonance and rate enhancement as high as 10 000× above the static Sabatier maximum. Dynamic catalytic reactions conducted at long times achieved oscillatory steady state differing from equilibrium consistent with the imposed surface oscillation amplitude acting as a ‘catalytic pump’ relative to the Gibbs free energy of reaction.