Heavy-Metal Adsorption Behavior of Two-Dimensional Alkalization-Intercalated MXene by First-Principles Calculations

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• 作者：Jianxin Guo ; Qiuming Peng ; Hui Fu ; Guodong Zou ; Qingrui Zhang
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：September 10, 2015
• 年：2015
• 卷：119
• 期：36
• 页码：20923-20930
• 全文大小：705K
• ISSN：1932-7455

文摘

The two-dimensional (2D) layered MXene (Ti₃C₂(OH)_xF_2鈥?i>x) material can be alkalization intercalated to achieve heavy-metal ion adsorption. Herein the adsorption kinetics of heavy-metal ions and the effect of intercalated sites on adsorption have been interpreted by first-principles with density functional theory. When the coverage of the heavy-metal ion is larger than 1/9 monolayer, the two-dimensional alkalization-intercalated MXene (alk-MXene: Ti₃C₂(OH)₂) exhibits strong heavy-metal ion absorbability. The hydrogen atoms around the adsorbed heavy-metal atom are prone to form a hydrogen potential trap, maintaining charge equilibrium. In addition, the ion adsorption efficiency of alk-MXene decreases due to the occupation of the F atom but accelerates by the intercalation of Li, Na, and K atoms. More importantly, the hydroxyl site vertical to the titanium atom shows a stronger trend of removing the metal ion than other positions.