Non‐Thermal Plasma Activation of Gold‐Based Catalysts for Low‐Temperature Water–Gas Shift Catalysis

Abstract

Non‐thermal plasma activation has been used to enable low‐temperature water‐gas shift over a Au/CeZrO4 catalyst. The activity obtained was comparable with that attained by heating the catalyst to 180 °C providing an opportunity for the hydrogen production to be obtained under conditions where the thermodynamic limitations are minimal. Using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), structural changes associated with the gold nanoparticles in the catalyst have been observed which are not found under thermal activation indicating a weakening of the Au−CO bond and a change in the mechanism of deactivation.

Activation and Deactivation of Gold/Ceria–Zirconia in the Low‐Temperature Water–Gas Shift Reaction

“…Furthermore, X‐ray energy‐dispersive spectroscopy (XEDS) analysis detected the presence of Au decorating the support where no particles were visible, implying the presence of unresolved subnanometer clusters or atomically dispersed Au on the CeZrO 4 surface. The difficulties in visualizing atomically dispersed Au on CeO 2 using HAADF imaging have been described previously . Figure S5 (Supporting Information) demonstrates that clearly distinguishing atomically dispersed surface Au from substitutional Zr atoms in the CeZrO 4 support is even more challenging.…”

Recent Advances in the Gold-Catalysed Low-Temperature Water–Gas Shift Reaction

“…The catalyst exhibited remarkably high activity under the NTP at close to room temperature-thermal contributions from the catalyst were accounted for and did not significantly contribute to the observed activity. It was concluded that under the NTP conditions, water was activated in the gas-phase [24]. Such unconventional methods of catalyst activation could be utilised to overcome thermodynamic limitations, as well as potentially stabilise the catalyst, as deactivation rates typically increase with reaction temperature.…”

One‐Step Reforming of CO2 and CH4 into High‐Value Liquid Chemicals and Fuels at Room Temperature by Plasma‐Driven Catalysis

“…These energetic species are capable of initiating av ariety of chemical reactions.Although much effort has been devoted to the use of NTPs for the degradation of gas pollutants,far less has been done with regard to their use in the synthesis of fuels and chemicals. [6] Previous work on DRM with NTPs mainly focused on syngas production, [7] while very limited efforts have been devoted to the challenging one-step conversion of CH 4 and CO 2 into liquid fuels and chemicals. [8,9] Afew groups have reported on the formation of trace oxygenates (e.g., alcohols and acids) as side products in plasma DRM for syngas production.…”