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Thermally regenerative electrochemical cycles and thermogalvanic cells harness redox entropy changes (ΔSrc) to interconvert heat and electricity with applications in heat harvesting and energy storage. Their efficiencies depend on ΔSrc because it relates directly to the Seebeck coefficient, yet few approaches exist for controlling the reaction entropy. Here, we demonstrate the design principle of using highly charged molecular species as electrolytes in thermogalvanic devices. As a proof-of-concept, the highly charged Wells-Dawson ion [P2W18O62]6– exhibits a large ΔSrc (−195 J mol–1 K–1) and a Seebeck coefficient comparable to state-of-the-art electrolytes (−1.7 mV K–1), demonstrating the potential of linking the rich chemistry of polyoxometalates to thermogalvanic technologies. 

In the context of CO 2 valorization, the possibility of shifting the selectivity of Ni catalysts from CO 2 methanation to reverse water gas shift reaction could be economically attractive provided that the catalyst presents sufficient activity and stability. Remarkably, the addition of sulfur (0.2–0.8% w/w) to nickel on a Ni/TiO 2 catalyst induces a complete shift in the catalyst selectivity for CO 2 hydrogenation at 340 °C from 99.7% CH 4 to 99.7% CO. At an optimal Ni/S atomic ratio of 4.5, the productivity of the catalyst reaches 40.5 mol CO 2 mol Ni −1 h −1 with a good stability. Density functional theory (DFT) calculations performed on various Ni surfaces reveal that the key descriptor of selectivity is the binding energy of the CO intermediate, which is related to the local electron density of surface Ni sites. 

Since the structure of supramolecular isomers determines their performance, rational synthesis of a specific isomer hinges on understanding the energetic relationships between isomeric possibilities. To this end, we have systematically interrogated a pair of uranium-based metal–organic framework topological isomers both synthetically and through density functional theory (DFT) energetic calculations. Although synthetic and energetic data initially appeared to mismatch, we assigned this phenomenon to the appearance of a metastable isomer, driven by levers defined by Le Châtelier's principle. Identifying the relationship between structure and energetics in this study reveals how non-equilibrium synthetic conditions can be used as a strategy to target metastable MOFs. Additionally, this study demonstrates how defined MOF design rules may enable access to products within the energetic phase space which are more complex than conventional binary ( e.g. , kinetic vs. thermodynamic) products.