Two-Dimensional Nb-Based M4C3 Solid Solutions (MXenes)

• Published in: Journal of the American Ceramic Society Vol. 99; no. 2; pp. 660 - 666
• Main Authors: Yang, Jian, Naguib, Michael, Ghidiu, Michael, Pan, Li-Mei, Gu, Jian, Nanda, Jagjit, Halim, Joseph, Gogotsi, Yury, Barsoum, Michel W.
• Format: Journal Article
• Language: English
• Published: Columbus Blackwell Publishing Ltd 01-02-2016; Wiley Subscription Services, Inc
• Subjects: Ceramics; Chemical synthesis; Diffraction; Energy storage; Intercalation; MXenes; Solid solutions; X-ray diffraction; Zirconium
• ISSN: 0002-7820; 1551-2916; 1551-2916
• DOI: 10.1111/jace.13922

Herein, two new two‐dimensional Nb4C3‐based solid solutions (MXenes), (Nb0.8,Ti0.2)4C3Tx and (Nb0.8,Zr0.2)4C3Tx (where T is a surface termination) were synthesized—as confirmed by X‐ray diffraction—from their corresponding MAX phase precursors (Nb0.8,Ti0.2)4AlC3 and (Nb0.8,Zr0.2)4AlC3. This is the first report on a Zr‐containing MXene. Intercalation of Li ions into these two compositions, and Nb4C3Tx was studied to determine the potential of those materials for energy storage applications. Lithiation and delithiation peaks at 2.26 and 2.35 V, respectively, appeared in the case of Nb4C3Tx, but were not present in Nb2CTx. After 20 cycles at a rate of C/4, the specific capacities of (Nb0.8,Ti0.2)4C3Tx and (Nb0.8,Zr0.2)4C3Tx were 158 and 132 mAh/g, respectively, both slightly lower than the capacity of Nb4C3Tx.