Abstract
Their complex surface chemistry and high oxygen lattice mobilities place mixed-metal oxides among the most important families of materials. Modulation of stoichiometry in mixed-metal oxides has been shown to be a very powerful tool for tuning optical and catalytic properties. However, accessing different stoichiometries is not always synthetically possible. Here, we show that the thermal decomposition of the recently reported metal-organic framework MUV-101(Fe, Ti) results in the formation of carbon-supported titanomaghemite nanoparticles with an unprecedented Fe/Ti ratio close to 2, not achievable by soft-chemistry routes. The resulting titanomaghemite phase displays outstanding catalytic activity for the production of CO from CO2 via the reverse water-gas shift (RWGS) reaction with CO selectivity values of ca. 100% and no signs of deactivation after several days on stream. Theoretical calculations suggest that the reaction proceeds through the formation of COOH∗ species, favoring in this way CO over other byproducts.
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•Heterometallic MOFs allow the synthesis of otherwise non-accessible materials•MOF-mediated synthesis of titanomaghemite with a Fe/Ti ratio close to 2•The resulting solid catalyzes the transformation of CO2 to CO
Carbon dioxide emissions and their implications for climate change are, most likely, the biggest challenge for our civilization. Yet, the complexity and scale of the issue have so far hampered progress in the implementation of technological solutions to address this challenge, especially in the area of CO2 utilization. This paper describes a new synthetic protocol that allows the synthesis of highly active and stable catalysts, based on abundant elements, for the direct transformation of CO2 to carbon monoxide, one of the most important chemical building blocks. On one hand, the new catalysts may allow the efficient valorization of CO2, turning this waste into an asset. On the other hand, this new synthetic protocol allows the manufacture of materials not accessible through traditional fabrication routes and has further applications in catalysis, sensing, and semiconductors.
An efficient catalyst for the valorization of carbon dioxide has been synthesized through the thermal decomposition of a heterometallic metal-organic framework (MOF). The work illustrates the exciting possibilities offered by heterometallic MOFs for the production of catalytic materials not accessible through traditional synthetic routes and opens the door to translating the atomic control of metal composition and distribution of the parent MOF onto complex mixed-oxide structures with industrial applications from heterogeneous catalysis to sensing and semiconductors.