2026-10-20 ミネソタ大学
＜関連情報＞
- https://cse.umn.edu/college/news/research-team-breaks-century-old-catalytic-speed-limit-more-1000-times
- https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010569/v1
- https://chemrxiv.org/doi/full/10.26434/chemrxiv.15004643/v1
サバティエ限界を超えるインターデジタテッド内部触媒コンデンサーを用いたフロー式ギ酸分解のプログラム制御 Programmable Formic Acid Decomposition in Flow on an Interdigitated Internal Catalytic Condenser Beyond the Sabatier Limit
Benjamin Auer, Chaehoon Kim, Wonwoo Lee, Jesse Canavan, Jaeheon Kim, Justin Hopkins, Dan McDonald, Matthew Neurock, C. Daniel Frisbie, Omar Abdelrahman, and Paul J. Dauenhauer
ChemRxiv Published:16 October 2026
Figure 1. Design and operating mechanism of the catalytic condenser.
Abstract
Rate modulation of non-Faradaic formic acid decomposition was evaluated on a Pt catalyst integrated within an interdigitated internal catalytic condenser in a continuous flow reactor. The condenser was fabricated on a quartz substrate with 50 μm digital spacing, with a counter electrode comprised of Au coated in 20 nm of SiO2 to suppress the hydrogen evolution reaction; a gel film comprised of ionic liquid, [EDMIM][TFSI], and fumed silica was spin coated over both electrodes across the device surface. The condenser exhibited capacitance of 18.6 μF cm-2 at reaction conditions of 125°C, with capacitance maintained above 1 μF cm-2 at frequencies up to ~10 Hz. The surface electric field was measured to be ~1 V nm⁻¹ using surface-enhanced Raman spectroscopy, with 4-mercaptobenzonitrile immobilized on an Ag electrode as a molecular electric-field probe. Inside a continuous flow reactor, the rate of CO2 and H2 formation from formic acid decomposition on Pt was shown to vary approximately an order of magnitude with applied potential, and non-Faradaic decomposition exhibited catalytic rates significantly faster than the Sabatier volcano maximum.
光子駆動触媒によるギ酸脱水素反応のサバティエ限界を超える Photon-Driven Catalytic Formic Acid Dehydrogenation Beyond the Sabatier Limit
Ali A. Mohammed https://orcid.org/0009-0004-9914-0544 amoham81@cougarnet.uh.edu, Ryan Berry, Silvia Marino, Kenneth Kusima, Michael J. Gordon, Lars C. Grabow, Paul J. Dauenhauer, Phillip Christopher, and Omar A. Abdelrahman
ChemRxiv Published:11 June 2026
Abstract
Sabatier scaling relationships impose fundamental limits on heterogeneous catalysis by coupling the energetics of reactant activation, intermediate stabilization, and product desorption. We show that visible photons circumvent this constraint by selectively removing a rate-limiting surface intermediate without changing the thermal catalytic energy landscape. Using formic acid decomposition on Pt, we demonstrated that 450 nm photon excitation reversibly promotes catalytic turnover by more than three orders of magnitude (4000x) beyond the thermal Sabatier-limited maximum while preserving 95% selectivity to dehydrogenation products, at an apparent quantum yield of 40%. Operando infrared spectroscopy showed that visible wavelength photons monotonically depleted linearly adsorbed CO*, the strongly bound intermediate accumulating to high steady-state coverage because thermal desorption is slow relative to its formation. Across excitation wavelengths, photon-driven rates collapse onto a single linear dependence on the extent of CO* depletion, identifying photon-promoted CO* desorption as the controlling event. Kinetic isotope experiments further separated the photon-driven and thermal pathways: thermal rates exhibited a primary formyl C–H isotope effect, while photon-driven rates did not, consistent with an isotope-insensitive CO* photodesorption step. With increasing photon flux, apparent formic acid reaction orders increased toward unity and apparent activation barriers decreased from 62 ± 3 kJ mol-1 toward zero, reflecting a photon-controlled shift from CO* coverage-dominated kinetics toward turnover governed by the intrinsic rate of formic acid activation. These findings demonstrate that photons break through Sabatier-imposed rate maxima not by modifying adsorption energies, but by shortening the lifetime of a strongly bound intermediate. This work establishes photon-regulated intermediate lifetimes as a strategy for catalytic performance beyond conventional thermochemical limits.
