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arXiv · 2306.10597

Mxenes for CO$\rm_{2}$ reduction and catalytically improved liquid hydrogen storage vie reverse water gas shift reaction

Tewodros Eyob Ada·Kenate Nemera Nigussa·Cecil N. M. Ouma
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Abstract

The catalytic reduction of $\mathrm{CO_{2}/CO}$ is an appealing approach for reducing greenhouse gas concentrations while also producing renewable energy. We used two-dimensional transitional metal carbides known as Mxenes as the most promising catalysts for boosted water-gas-shift reaction for conversion of $\mathrm{CO_{2}}$ to chemical fuel and liquid hydrogen. Our findings reveal that the $\mathrm{Ti_{2}C}$ surface collects $\mathrm{CO_{2}}$ and converts it to reactive carbon mono oxide gas and oxygen termination. Surface catalytic reactions always start with $\mathrm{CO}$ hydrogenation, which is sustained by a continual supply of water at the optimum temperature. $\mathrm{Ti_{2}C}$ surface terminations are in charge of the formation of molecules, free radicals, and alcohols, and the conversion reaction is cycled frequently, producing methanol, methane, water, and hydrogen molecules with each cycle. Furthermore, once water is injected for system hydrogenation, the $\mathrm{Ti_{2}C}$ surface has the ability to hydrogenate itself, because water breaks down into its constituents $\mathrm{O}$ and $\mathrm{OH}$ in the presence of free radicals such as $\mathrm{H_{2}CO}$. Thus, self hydrogenation increases liquid hydrogen generation in addition to the usage of water for hydrogen supply.

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Tewodros Eyob Ada, Kenate Nemera Nigussa, Cecil N. M. Ouma. 2023-06-18. Mxenes for CO$\rm_{2}$ reduction and catalytically improved liquid hydrogen storage vie reverse water gas shift reaction. https://arxiv.org/abs/2306.10597

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