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DOE OSTI · 1993034

Influence of MXene termination groups on hydrogen interactions

Mahoney, Ashe·Ward, Patrick A.
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Abstract

MXenes are a relatively new class of nanomaterial consisting of alternating layers of transition metals and carbon or nitrogen, capped off on either end by terminal groups, usually from the P-block. They have been considered for a wide range of purposes, including hydrogen storage. In this study, thermogravimetric analysis and mass spectrometry residual gas analysis are performed on Ti 3 C 2 T x and Ti 2 CT x to characterize their terminal groups. The hydrogen absorption capabilities of the heat-treated samples are measured using a Sievert apparatus and compared against untreated samples. This reveals that, during heating, the MXenes lose hydrogen, water, fluoride, hydrofluoric acid, and carbon dioxide. Isothermal absorption measurements suggest that the removal of termination groups might improve hydrogen uptake kinetics at high temperatures, but has little effect at room temperatures.

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Mahoney, Ashe, Ward, Patrick A.. 2023-07-21. Influence of MXene termination groups on hydrogen interactions. https://doi.org/10.2172/1993034

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