Two-dimensional (2D) transition metal carbides and nitrides, known as MXenes, are a large class of materials that are finding numerous applications ranging from energy storage and electromagnetic interference shielding to water purification and antibacterial coatings. Yet, despite the fact that more than 20 different MXenes have been synthesized, the mechanical properties of a MXene monolayer have not been experimentally studied. We measured the elastic properties of monolayers and bilayers of the most important MXene material to date, Ti₃C₂T _x (T _x stands for surface termination). We developed a method for preparing well-strained membranes of Ti₃C₂T _x monolayers and bilayers, and performed their nanoindentation with the tip of an atomic force microscope to record the force-displacement curves. The effective Young's modulus of a single layer of Ti₃C₂T _x was found to be 0.33 ± 0.03 TPa, which is the highest among the mean values reported in nanoindentation experiments for other solution-processed 2D materials, including graphene oxide. This work opens a pathway for investigating the mechanical properties of monolayers and bilayers of other MXenes and extends the already broad range of MXenes' applications to structural composites, protective coatings, nanoresonators, and membranes that require materials with exceptional mechanical properties.

中文翻译：

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2D Ti3C2T x MXene单层和双层的弹性性能。

二维（2D）过渡金属碳化物和氮化物，称为MXenes，是一类广泛的材料，正在发现许多应用，从能量存储和电磁干扰屏蔽到水净化和抗菌涂层。然而，尽管已经合成了20多种不同的MXene，但尚未通过实验研究MXene单层的机械性能。我们测量了迄今为止最重要的MXene材料Ti ₃ C ₂ T _x（T _x表示表面终止）的单层和双层的弹性性能。我们开发了一种制备应变良好的Ti ₃ C ₂ T _x膜的方法 单层和双层，并用原子力显微镜的尖端进行纳米压痕，以记录力-位移曲线。发现单层Ti ₃ C ₂ T _x的有效杨氏模量为0.33±0.03 TPa，在纳米压痕实验中报道的其他溶液处理2D材料（包括氧化石墨烯）的平均值中最高。这项工作为研究其他MXene的单层和双层的机械性能开辟了道路，并将MXene的广泛应用范围扩展到需要具有优异机械性能的材料的结构复合材料，保护涂层，纳米谐振器和膜。