Interface Catalysts of In Situ-Grown TiO₂/MXenes for High-Faraday-Efficiency CO₂ Reduction

Authors

Shaun Debow, Aberdeen Proving Ground
Zichen Shen, Utah State University
Arjun Sathyan Kulathuvayal, University of Oklahoma
Fuzhan Song, Utah State University
Tong Zhang, Utah State University
Haley Fisher, Utah State University
Jesse B. Brown, Utah State University
Yuqin Qian, Utah State University
Zhi-Chao Huang-Fu, Utah State UniversityFollow
Hui Wang, Utah State UniversityFollow
Zachary Zander, Aberdeen Proving GroundFollow
Mark S. Mirotznik, University of DelawareFollow
Robert L. Opila, University of DelawareFollow
Yanqing Su, University of OklahomaFollow
Yi Rao, Utah State UniversityFollow

Document Type

Article

Author ORCID Identifier

Zichen Shen https://orcid.org/0000-0002-4792-8178

Arjun Sathyan Kulathuvayal https://orcid.org/0000-0003-1752-6781

Yuqin Qian https://orcid.org/0000-0001-8393-819X

Zhi-Chao Huang-Fu https://orcid.org/0000-0001-8673-0204

Hui Wang https://orcid.org/0000-0003-1039-7833

Robert L. Opila https://orcid.org/0000-0002-5024-7402

Yanqing Su https://orcid.org/0000-0003-0790-5905

Yi Rao https://orcid.org/0000-0001-9882-1314

Journal/Book Title/Conference

Molecules

Volume

30

Issue

19

Publisher

MDPI AG

Publication Date

10-9-2025

Journal Article Version

Version of Record

First Page

1

Last Page

14

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

Abstract

Climate change and the global energy crisis have led to an increasing need for greenhouse gas remediation and clean energy sources. The electrochemical CO₂ reduction reaction (CO₂RR) is a promising solution for both issues as it harvests waste CO₂ 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 TiO₂ nanoparticles grown in situ on MXene charge acceptor 2D sheets with excellent CO₂RR characteristics. A straightforward solvothermal method was used to grow the nanoparticles on the Ti₃C₂T_x MXene flakes. The electrochemical performance of the TiO₂/MXene electrodes was analyzed. The Faradaic efficiencies of the TiO₂/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 CO₂²⁻ intermediates. Bader charge analysis corroborated this pathway, showing that CO₂ gains a greater negative charge when TiO₂/MXene serves as a catalyst compared to MXene or TiO₂ alone. These results show that TiO₂/MXene nanocomposite electrodes may be very useful in the conversion of CO₂ while still being efficient in both time and cost.

Recommended Citation

Debow, S.; Shen, Z.; Kulathuvayal, A.S.; Song, F.; Zhang, T.; Fisher, H.; Brown, J.B.; Qian, Y.; Huang-Fu, Z.-C.; Wang, H.; et al. Interface Catalysts of In Situ-Grown TiO2/MXenes for High-Faraday-Efficiency CO2 Reduction. Molecules 2025, 30, 4025. https://doi.org/10.3390/molecules30194025