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

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Catalysis Chemistry Waveform Catalytic cycle Chemical physics Kinetics Work (physics) Resonance (particle physics) Thermodynamics Physics Atomic physics Classical mechanics Quantum mechanics Voltage Biochemistry

M. Alexander Ardagh , Omar Abdelrahman , Paul J. Dauenhauer ·

YOU? · · 2019 · Open Access · · DOI: https://doi.org/10.1021/acscatal.9b01606 · OA: W2945032606

Acceleration\nof the catalytic transformation of molecules via heterogeneous\nmaterials occurs through design of active binding sites to optimally\nbalance the requirements of all steps in a catalytic cycle. In accordance\nwith the Sabatier principle, the characteristics of a single binding\nsite are balanced between at least two transient phenomena, leading\nto maximum possible catalytic activity at a single, static condition\n(i.e., a “volcano curve” peak). In this work, a dynamic\nheterogeneous catalyst oscillating between two electronic states was\nevaluated via simulation, predicting catalytic activity as much as\nthree-to-four orders of magnitude (1000–10 000) above\nthe Sabatier maximum. Surface substrate binding energies were varied\nby a given amplitude (0.1 < ΔU < 3.0\neV) over a broad range of frequencies (10–4 < f < 1011 s–1) in square,\nsinusoidal, sawtooth, and triangular waveforms to characterize surface\ndynamics impact on average catalytic turnover frequency. Catalytic\nsystems were shown to exhibit order-of-magnitude dynamic rate enhancement\nat “surface resonance” defined as the band of frequencies\n(e.g., 103–107 s–1)\nwhere the applied surface waveform kinetics were comparable to kinetics\nof individual microkinetic chemical reaction steps. Key dynamic performance\nparameters are discussed regarding industrial catalytic chemistries\nand implementation in physical dynamic systems operating above kilohertz\nfrequencies.