| Summary: | Climate change and the global energy crisis have led to an increasing need for greenhouse gas remediation and clean energy sources. The electrochemical CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR) is a promising solution for both issues as it harvests waste CO<sub>2</sub> and chemically reduces it to more useful forms. However, the high overpotential required for the reaction makes it electrochemically unfavorable. Here, we fabricate a novel electrode composed of TiO<sub>2</sub> nanoparticles grown in situ on MXene charge acceptor 2D sheets with excellent CO<sub>2</sub>RR characteristics. A straightforward solvothermal method was used to grow the nanoparticles on the Ti<sub>3</sub>C<sub>2</sub>T<i><sub>x</sub></i> MXene flakes. The electrochemical performance of the TiO<sub>2</sub>/MXene electrodes was analyzed. The Faradaic efficiencies of the TiO<sub>2</sub>/MXene electrodes were determined, with a value of 99.41% at −1.9 V (vs. Ag/AgCl). Density functional theory mechanistic analysis was used to reveal the most likely mechanism resulting in the production of one CO molecule along with a carbonate anion through ∗CO, ∗O, and activated CO<sub>2</sub><sup>2−</sup> intermediates. Bader charge analysis corroborated this pathway, showing that CO<sub>2</sub> gains a greater negative charge when TiO<sub>2</sub>/MXene serves as a catalyst compared to MXene or TiO<sub>2</sub> alone. These results show that TiO<sub>2</sub>/MXene nanocomposite electrodes may be very useful in the conversion of CO<sub>2</sub> while still being efficient in both time and cost.
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