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Since climate change keeps escalating, it is imperative that the increasing CO 2 emissions be combated. Over recent years, research efforts have been aiming for the design and optimization of materials for CO 2 capture and conversion to enable a circular economy. The uncertainties in the energy sector and the variations in supply and demand place an additional burden on the commercialization and implementation of these carbon capture and utilization technologies. Therefore, the scientific community needs to think out of the box if it is to find solutions to mitigate the effects of climate change. Flexible chemical synthesis can pave the way for tackling market uncertainties. The materials for flexible chemical synthesis function under a dynamic operation, and thus, they need to be studied as such. Dual-function materials are an emerging group of dynamic catalytic materials that integrate the CO 2 capture and conversion steps. Hence, they can be used to allow some flexibility in the production of chemicals as a response to the changing energy sector. This Perspective highlights the necessity of flexible chemical synthesis by focusing on understanding the catalytic characteristics under a dynamic operation and by discussing the requirements for the optimization of materials at the nanoscale., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Climate change is becoming increasingly more pronounced every day while the amount of greenhouse gases in the atmosphere continues to rise. CO 2 reduction to valuable chemicals is an approach that has gathered substantial attention as a means to recycle these gases. Herein, some of the tandem catalysis approaches that can be used to achieve the transformation of CO 2 to C-C coupled products are explored, focusing especially on tandem catalytic schemes where there is a big opportunity to improve performance by designing effective catalytic nanoreactors. Recent reviews have highlighted the technical challenges and opportunities for advancing tandem catalysis, especially highlighting the need for elucidating structure-activity relationships and mechanisms of reaction through theoretical and in situ / operando characterization techniques. In this review, the focus is on nanoreactor synthesis strategies as a critical research direction, and discusses these in the context of two main tandem pathways (CO-mediated pathway and Methanol-mediated pathway) to C-C coupled products., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Global Challenges published by Wiley‐VCH GmbH.)

The feasibility of a Dual Function Material (DFM) with a versatile catalyst offering switchable chemical synthesis from carbon dioxide (CO 2 ) was demonstrated for the first time, showing evidence of the ability of these DFMs to passively capture CO 2 directly from the air as well. These DFMs open up possibilities in flexible chemical production from dilute sources of CO 2 , through a combination of CO 2 adsorption and subsequent chemical transformation (methanation, reverse water gas shift or dry reforming of methane). Combinations of Ni Ru bimetallic catalyst with Na 2 O, K 2 O or CaO adsorbent were supported on CeO 2 -Al 2 O 3 to develop flexible DFMs. The designed multicomponent materials were shown to reversibly adsorb CO 2 between the 350 and 650 °C temperature range and were easily regenerated by an inert gas purge stream. The components of the flexible DFMs showed a high degree of interaction with each other, which evidently enhanced their CO 2 capture performance ranging from 0.14 to 0.49 mol kg -1 . It was shown that captured CO 2 could be converted into useful products through either CO 2 methanation, reverse water-gas shift (RWGS) or dry reforming of methane (DRM), which provides flexibility in terms of co-reactant (hydrogen vs . methane) and end product (synthetic natural gas, syngas or CO) by adjusting reaction conditions. The best DFM was the one containing CaO, producing 104 μmol of CH 4 per kg DFM in CO 2 methanation, 58 μmol of CO per kg DFM in RWGS and 338 μmol of CO per kg DFM in DRM.

The reverse water gas shift reaction (RWGS) has attracted much attention as a potential means to widespread utilization of CO 2 through the production of synthesis gas. However, for commercial implementation of RWGS at the scales needed to replace fossil feedstocks with CO 2 , new catalysts must be developed using earth abundant materials, and these catalysts must suppress the competing methanation reaction completely while maintaining stable performance at elevated temperatures and high conversions producing large quantities of water. Herein we identify molybdenum phosphide (MoP) as a nonprecious metal catalyst that satisfies these requirements. Supported MoP catalysts completely suppress methanation while undergoing minimal deactivation, opening up possibilities for their use in CO 2 utilization., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Fischer-Tropsch synthesis (FTS) is an essential approach to convert coal, biomass, and shale gas into fuels and chemicals, such as lower olefins, gasoline, diesel, and so on. In recent years, there has been increasing motivation to deploy FTS at commercial scales which has been boosting the discovery of high performance catalysts. In particular, the importance of support in modulating the activity of metals has been recognized and carbonaceous materials have attracted attention as supports for FTS. In this review, we summarised the substantial progress in the preparation of carbon-based catalysts for FTS by applying activated carbon (AC), carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon spheres (CSs), and metal-organic frameworks (MOFs) derived carbonaceous materials as supports. A general assessment of carbon-based catalysts for FTS, concerning the support and metal properties, activity and products selectivity, and their interactions is systematically discussed. Finally, current challenges and future trends in the development of carbon-based catalysts for commercial utilization in FTS are proposed.

Methanol is a major fuel and chemical feedstock currently produced from syngas, a CO/CO 2 /H 2 mixture. Herein we identify formate binding strength as a key parameter limiting the activity and stability of known catalysts for methanol synthesis in the presence of CO 2 . We present a molybdenum phosphide catalyst for CO and CO 2 reduction to methanol, which through a weaker interaction with formate, can improve the activity and stability of methanol synthesis catalysts in a wide range of CO/CO 2 /H 2 feeds., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)