Büchner, Carina;
Kubitza, Niels;
Malik, Ali M;
Jamboretz, John;
Riaz, Aysha A;
Zhu, Yujiang;
Schlueter, Christoph;
... Birkel, Christina S; + view all
(2024)
Chemical Conversions within the Mo–Ga–C System: Layered Solids with Variable Ga Content.
Inorganic Chemistry
, 63
(17)
pp. 7725-7734.
10.1021/acs.inorgchem.4c00107.
![[thumbnail of Mo2Ga2C_Birkel_rev.pdf]](https://discovery.ucl.ac.uk/style/images/fileicons/text.png) |
Text
Mo2Ga2C_Birkel_rev.pdf - Accepted Version Access restricted to UCL open access staff until 17 April 2025. Download (1MB) |
Abstract
Layered carbides are fascinating compounds due to their enormous structural and chemical diversity, as well as their potential to possess useful and tunable functional properties. Their preparation, however, is challenging and forces synthesis scientists to develop creative and innovative strategies to access high-quality materials. One unique compound among carbides is Mo₂Ga₂C. Its structure is related to the large and steadily growing family of 211 MAX phases that crystallize in a hexagonal structure (space group P6₃/mmc) with alternating layers of edge-sharing M₆X octahedra and layers of the A-element. Mo₂Ga₂C also crystallizes in the same space group, with the difference that the A-element layer is occupied by two A-elements, here Ga, that sit right on top of each other (hence named “221” compound). Here, we propose that the Ga content in this compound is variable between 2:2, 2:1, and 2: ≤1 (and 2:0) Mo/Ga ratios. We demonstrate that one Ga layer can be selectively removed from Mo₂Ga₂C without jeopardizing the hexagonal P6₃/mmc structure. This is realized by chemical treatment of the 221 phase Mo₂Ga₂C with a Lewis acid, leading to the “conventional” 211 MAX phase Mo₂GaC. Upon further reaction with CuCl₂, more Ga is removed and replaced with Cu (instead of fully exfoliating into the Ga-free Mo₂CTx MXene), leading to Mo₂Ga₁₋ₓCuₓC still crystallizing with space group P6₃/mmc, however, with a significantly larger c-lattice parameter. Furthermore, 211 Mo₂GaC can be reacted with Ga to recover the initial 221 Mo₂Ga₂C. All three reaction pathways have not been reported previously and are supported by powder X-ray diffraction (PXRD), electron microscopy, X-ray spectroscopy, and density functional theory (DFT) calculations.
| Type: | Article |
|---|---|
| Title: | Chemical Conversions within the Mo–Ga–C System: Layered Solids with Variable Ga Content |
| Location: | United States |
| DOI: | 10.1021/acs.inorgchem.4c00107 |
| Publisher version: | https://doi.org/10.1021/acs.inorgchem.4c00107 |
| Language: | English |
| Additional information: | This version is the author-accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10194590 |
Archive Staff Only
 |
View Item |
