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To control anthropogenic CO2 emissions worldwide, it is necessary not only to align the chemical industry and energy sector with renewable resources but also to implement large‐scale utilization of CO2 as a feedstock. The Fe‐catalyzed CO2‐modified Fischer‐Tropsch Synthesis (CO2‐FTS) is one of the most promising options for efficient CO2 utilization, as it can be used to synthesize desired higher hydrocarbons (C2+), including lower olefins (C2=‐C4=), the main building blocks of the chemical industry, and long‐chain hydrocarbons (C5+), which can be used as fuels. To optimize catalyst and process design for the purpose of developing an economically viable industrial process, the reaction mechanism and the factors controlling product selectivity need to be fully understood. This article discusses the current state‐of‐the‐art in catalyst design and approaches for making effective progress in addressing these challenges. [ABSTRACT FROM AUTHOR]

A detailed operando DRIFTS study on the CO2 Fischer‐Tropsch reaction with K‐promoted Fe/YZrOx catalysts was performed to investigate the influence of this modification on the catalytic performance in the formation of lower olefins as well as higher hydrocarbons and to gain insights into mechanistic aspects. Catalytic testing revealed an enhanced formation of olefins and hydrocarbons by adding potassium to the catalysts, while spectroscopic studies revealed various stable adsorbates and intermediates such as monodentate carbonates, bicarbonates, formates, formyl, and methoxy on the surface of the K‐promoted Fe/YZrOx catalysts compared to the unpromoted one. Based on gas‐feed switching experiments and statistical analysis of literature IR data regarding Fe‐containing catalysts, it was found that carbonate species interacting with H2 are transformed to higher hydrocarbons and methane via formate and formyl formation, while bicarbonate species are decomposed accompanied by the formation of CO, which then further reacts to form formate or formyl and finally hydrocarbons. [ABSTRACT FROM AUTHOR]

Reverse water-gas shift (RWGS) reaction has attracted much attention as a potential approach for CO 2 valorization via the production of synthesis gas, especially over Fe-modified supported Cu catalysts on CeO 2 . However, most studies have focused solely on investigating the RWGS reaction over catalysts with high Cu and Fe loadings, thus leading to an increase in the complexity of the catalytic system and, hence, preventing the gain of any reliable information about the nature of the active sites and reaction mechanism. In this work, a CeO 2 -supported single-atom Cu catalyst modified with iron was synthesized and evaluated for the RWGS reaction. The catalytic results reveal a significant synergistic effect between CuCeO 2 and Fe, demonstrating an activity up to three times higher than the combined catalytic activities of monometallic catalysts (Fe/CeO 2 + CuCeO 2 ) under identical conditions. Various ex situ and in situ/operando techniques are employed to unveil the concealed role of Fe in catalyst activity enhancement. The combined findings from hydrogen temperature-programmed reduction (H 2 -TPR) and operando electron paramagnetic resonance spectroscopy (EPR) reveal that the added Fe predominantly interacts with Cu-containing surface sites, resulting in the stabilization of higher proportions of Cu single sites. Near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) and operando EPR results unveil a synergistic interplay of Fe with Cu-containing sites and CeO x domains, efficiently enhancing both the reoxidation of Cu + in Cu + -O v -Ce 3+ moieties and the reducibility of Ce 4+ in CeO x domains under RWGS conditions. Detailed mechanistic studies reveal that the RWGS reaction predominantly proceeds via the redox mechanism., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)