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In recent years, the catalytic dry reforming of methane (DRM) has increasingly come into academic focus. The interesting aspect of this reaction is seemingly the conversion of CO2 and methane, two greenhouse gases, into a valuable synthesis gas (syngas) mixture with an otherwise unachievable but industrially relevant H2/CO ratio of one. In a possible scenario, the chemical conversion of CO2 and CH4 to syngas could be used in consecutive reactions to produce synthetic fuels, with combustion to harness the stored energy. Although the educts of DRM suggest a superior impact of this reaction to mitigate global warming, its potential as a chemical energy converter and greenhouse gas absorber has still to be elucidated. In this review article, we will provide insights into the industrial maturity of this reaction and critically discuss its applicability as a cornerstone in the energy transition. We derive these insights from assessing the current state of research and knowledge on DRM. We conclude that the entire industrial process of syngas production from two greenhouse gases, including heating with current technologies, releases at least 1.23 moles of CO2 per mol of CO2 converted in the catalytic reaction. Furthermore, we show that synthetic fuels derived from this reaction exhibit a negative carbon dioxide capturing efficiency which is similar to burning methane directly in the air. We also outline potential applications and introduce prospective technologies toward a net-zero CO2 strategy based on DRM.

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Several in situ studies have revealed spatiotemporal dynamics on heterogeneous catalysts surfaces under chemical stimuli1-4, which presumably control the activity, selectivity, and productivity5-11. However, operando validations of sufficient spacetime resolution12 are often missing, and hence, the effect of these dynamics on catalytic performance may not be entirely clear. Here, using dry reforming of methane over Ni as an example, we demonstrate the relevance of catalytic redox dynamics for reaction performance and determine their genesis from adaptive chemistry and continual catalytic cycling. By combining operando scanning electron microscopy and near-ambient-pressure X-ray photoelectron spectroscopy, we found that activation sites for methane and carbon dioxide differed but continually transformed into each other during the reaction. This behavior enabled a self-sustained oscillating regime evincing the sequential formation of active sites. We also found that not all spatiotemporal dynamics accounted for the catalytic function. We highlight the importance of oscillating reactions for mechanistic studies and propose that the generation of mechanical strain at the catalyst during redox cycling acted as a feedback element for the oscillations. These observations lead to deeper understanding of fundamental catalysis and open new opportunities for tuning catalytic performances.