The shelf life of 2D MXenes in functional devices and colloidal dispersions is compromised due to oxidation in the aqueous system. Herein, a systematic investigation is carried out to explore the potential of various amino compounds as antioxidants for Ti3C2Tx MXenes. A range of basic, acidic, and neutral amino acids were examined for their effectiveness, where certain antioxidants failed to protect MXenes from oxidation, while others accelerated their decomposition. Serine, threonine, and asparagine demonstrated excellent antioxidant activity, likely due to their evenly distributed molecular charges. These neutral amino acids outperformed glutamic acid, which possesses an electron-withdrawing -COOH group, and lysine, with an electron-donating -NH2 group. Serine functionalized MXene realized a stabilization time constant reaching 128 days, as determined by first-order reaction kinetics. Additionally, when employed as supercapacitor electrodes, aged MXene and serine-functionalized MXene exhibited specific capacitance values of 219.2 and 280.3 F g-1 at 5 A g-1 after 6 weeks, respectively. This work addresses a gap in the practical work on ionic stabilization of 2D MXenes and has significant implications for the long-term colloidal storage of MXenes using greener chemicals.

中文翻译：

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探索氨基化合物在水性环境中减轻 2D Ti3C2Tx MXene 纳米片氧化中的协同作用


由于水性体系中的氧化，2D MXenes 在功能器件和胶体分散体中的保质期受到影响。在此，进行了系统的研究，以探索各种氨基化合物作为 Ti3C2Tx MXenes 抗氧化剂的潜力。检查了一系列碱性、酸性和中性氨基酸的有效性，其中某些抗氧化剂无法保护 MXenes 免受氧化，而另一些则加速了它们的分解。丝氨酸、苏氨酸和天冬酰胺表现出优异的抗氧化活性，这可能是由于它们均匀分布的分子电荷。这些中性氨基酸的性能优于谷氨酸，谷氨酸具有吸电子 -COOH 基团，赖氨酸具有电子供体 -NH2 基团。丝氨酸功能化的 MXene 实现了达到 128 天的稳定时间常数，由一级反应动力学确定。此外，当用作超级电容器电极时，老化的 MXene 和丝氨酸官能化的 MXene 在 6 周后在 5 A g-1 下的比电容值分别为 219.2 和 280.3 F g-1。这项工作解决了 2D MXenes 离子稳定化实际工作中的空白，并对使用更环保化学品的 MXenes 的长期胶体储存具有重要意义。