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Double transition metal (DTM) nitride MXenes offer enhanced electrical conductivity and tunable catalytic properties compared to conventional carbide-based MXenes. In this study, we employed first-principles density functional theory (DFT) calculations to discover and computationally validate a novel DTM nitride MXene, Nb2TiN2, derived from its MAX phase precursor and investigated its potential as an anchoring material (AM) for Li–Se batteries. This newly proposed MXene expands the compositional landscape of DTM nitrides and opens new avenues for functional material design. We performed a comprehensive analysis of the thermodynamic and electronic properties of Nb2TiAlN2, and the MAX phase precursor to Nb2TiN2 to assess its structural stability and exfoliation potential. Exfoliation energy calculations confirmed the feasibility of synthesizing Nb2TiN2 from Nb2TiAlN2. We then explored the functionalized form, Nb2TiN2S2, evaluating its capability to serve as an effective anchoring material (AM) in Li–Se batteries by analyzing the reaction mechanisms and kinetics of the selenium reduction reaction (SeRR). Our results indicate that Nb2TiN2S2 exhibits a strong binding affinity for lithium polyselenides (Li2Sen), effectively suppressing the shuttle effect. Gibbs free energy calculations for the rate-limiting step of the SeRR reveal favorable kinetics and reduced reaction barriers. Overall, this study provides a detailed evaluation of the structural and electronic properties of a newly proposed DTM nitride MXene and its S-functionalized derivative and the catalyzing effect of Nb2TiN2S2 in accelerating the reaction kinetics in Li–Se batteries. These findings underscore the potential importance of the further exploration of MXenes to address current challenges in high-performance Li–Se batteries.
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This content will become publicly available on January 13, 2027
Confinement of quasi-atomic structures in Ti2N and Ti3N2 MXene electrides
Metal carbides, nitrides, or carbonitrides of early transition metals, better known as MXenes, possess notable structural, electrical, and magnetic properties. Analyzing electronic structures by calculating structural stability, band structure, density of states, Bader charge transfer, and work functions utilizing first principle calculations, we revealed that titanium nitride MXenes, namely TiN and TiN, have excess anionic electrons in their lattice voids, making them MXene electrides. Bulk TiN has competing antiferromagnetic (AFM) and ferromagnetic(FM) configurations with slightly more stable AFM configuration, while the TiN MXene is nonmagnetic. Although TiN favors AFM configuration with hexagonal crystal systems having point group symmetry, TiN does not support altermagnetism. The monolayer of the TiN MXene is a ferromagnetic electride. These unique properties of having non-nuclear interstitial anionic electrons in the electronic structure of titanium nitride MXene have not yet been reported in the literature. Density functional theory calculations show TiN is neither an electride, MXene, or magnetic.
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- Award ID(s):
- 2004197
- PAR ID:
- 10659663
- Publisher / Repository:
- Journal of Physics and Chemistry of Solids
- Date Published:
- Journal Name:
- Journal of Physics and Chemistry of Solids
- ISSN:
- 0022-3697
- Page Range / eLocation ID:
- 113534
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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