对太赫兹（THz）波的传输调控是THz光学系统设计、通信、成像应用等领域的基础技术之一。界面阻抗匹配效应可以用于实现高效THz波反射调控，但尚未见硅基界面阻抗设计实现THz波调控的报道。本研究利用自组装法在高阻硅基底上制备MXene膜层，通过增加膜层厚度改变其电阻特性，进而连续调节Si/MXene/空气界面阻抗，实现高效的THz波减反射。在接近阻抗匹配态时，界面THz波反射率减少幅度达83%，透过率衰减约为30%。还利用THz波层析扫描成像技术，得到了Si/MXene/空气界面阻抗变化导致的THz波反射强度变化趋势。设计的具有高效THz波反射调控性能的Si基功能界面为THz波传输调控提供了一种新思路。

光热治疗以其无创性、非侵入性、副作用小等特点受到了广泛关注。二维碳化钛（MXene）作为一种新型纳米材料，具有优异的物理和化学性能，其中包括良好的光热效应。本课题组通过静电吸附作用构建了基于MXene的光热/化疗协同治疗纳米试剂，该纳米试剂具有优异的消光系数［24.05 L/（g·cm）］以及出色的光热转效率（31.34%）。体外细胞实验结果表明该纳米对HepG2细胞起到了良好的抑制效果，经其治疗后的细胞存活率仅为21.09%。

MXene V₂CT_x has great practicability because it is not easy to degrade under ambient conditions. In this paper, a V₂CT_x saturable absorber (SA) was firstly applied to a passively Q-switched (PQS) laser, to the best of our knowledge. The V₂CT_x-SA was prepared by the spin-coating method. The linear absorption of the V₂CT_x-SA in the 1000–2200 nm region and the nonlinear absorption near 2 µm were studied. With the V₂CT_x-SA, a typical PQS operation at 1.94 µm was realized in a Tm:YAlO3 laser. The minimum pulse width produced by the PQS laser was 528 ns, and the peak power, repetition rate, and average output power were 10.06 W, 65.9 kHz, and 350 mW, respectively. Meanwhile, the maximum pulse energy was 6.33 µJ. This work demonstrates that the V₂CT_x can be used as an effective SA to obtain nanosecond pulses with high peak power and high repetition rate simultaneously.

银基电触头在低压开关领域扮演重要角色。作为一种具有良好导电导热性能的新型二维碳化物材料,MXene家族典型代表材料(Ti₃C₂T_x)在多个领域显示出极大的应用潜力。Ti₃C₂T_x有望作为一种新型环保银基电触头增强相材料。本研究采用粉末冶金法制备了Ag/Ti₃C₂T_x复合材料,并对Ti₃C₂T_x和Ti₃AlC₂的物相和微观结构进行表征。同时研究了Ti₃C₂T_x增强Ag基复合材料的综合性能,包括电阻率、显微硬度、机械加工性能、抗拉强度和抗电弧侵蚀性能,并与Ti₃AlC₂增强Ag基复合材料进行了比较。Ag/Ti₃C₂T_x的电阻率(30×10 ^-3 μΩ·m)相对于Ag/Ti₃AlC₂(42×10 ^-3 μΩ·m)降低了29%。Ag/Ti₃C₂T_x硬度适中(64 HV),具有良好的可加工性,作为无毒电触头材料应用前景广阔。Ag/Ti₃C₂T_x复合材料导电性能的提高主要归因于Ti₃C₂T_x本身优异的金属性以及由Ti₃C₂T_x微观结构特征带来的可变形性。由于缺乏Al-Ag相互扩散,Ag/Ti₃C₂T_x复合材料的拉伸强度(32.77 MPa)明显低于Ag/Ti₃AlC₂复合材料(145.52 MPa)。正因为缺失Al层,Ag/Ti₃C₂T_x的抗电弧侵蚀性能也无法与Ag/Ti₃AlC₂相媲美。尽管Ag/Ti₃C₂T_x的抗电弧侵蚀性能有待进一步提高,但优异的导电性使其有望替代当下有毒的Ag/CdO电接触材料。该研究结果为开发新型环保电触头材料提供了新的探索方向。

MXene (M_n+1X_n) is an emerging class of layered two-dimensional (2D) materials, which are derived from their bulk-state MAX phase (M_n+1AX_n, where M: early transition metal, A: group element 13 and 14, and X: carbon and/or nitrogen). MXenes have found wide-ranging applications in energy storage devices, sensors, catalysis, etc. owing to their high electronic conductivity and wide range of optical absorption. However, the absence of semiconducting MXenes has limited their applications related to light emission. Research has shown that quantum dots (QDs) derived from MXene (MQDs) not only retain the properties of the parent MXene but also demonstrate significant improvement on light emission and quantum yield (QY). The optical properties and photoluminescence (PL) emission mechanisms of these light-emitting MQDs have not been comprehensively investigated. Recently, work on light-emitting MQDs has shown good progress, and MQDs exhibiting multi-color PL emission along with high QY have been fabricated. The synthesis methods also play a vital role in determining the light emission properties of these MQDs. This review provides an overview of light-emitting MQDs and their synthesis methods, optical properties, and applications in various optical, sensory, and imaging devices. The future prospects of light-emitting MQDs are also discussed to provide an insight that helps to further advance the progress on MQDs.

作为一种新兴的二维材料,MXene是一种具有潜力的非线性光学材料,为此制备Nb₂C纳米片并使用分光光度计测量其吸收谱。首先通过氢氟酸刻蚀和液相剥离来制备Nb₂C纳米片,然后使用扫描电子显微镜来表征其形貌,最后通过实验对其进行讨论。实验结果表明,MXene所修饰的微纳光纤器件可以在通信波段实现四波混频现象,四波混频的转换效率增强5 dB;对于恒定的泵浦光,信号光的波长变化范围约为4 nm;当波长间隔为0.4 nm时,逐渐增加信号光和泵浦光的放大功率,则四波混频的转换效率会逐渐增加,转换效率和入射功率呈线性关系,转换效率并未出现饱和,为此其具有进一步提升的空间。

高强电磁屏蔽薄膜材料在柔性器件、汽车电子和航空航天等领域具有广泛应用前景, 受珍珠母微纳米结构及其优异机械性能的启发, 利用简单的溶液共混及真空抽滤方法, 将纤维素纳米晶(CNC)和MXene混合, 经层层组装制备了高性能MXene基复合薄膜。结果表明: 薄膜的机械性能有了显著提高, 拉伸强度从18 MPa提高到57 MPa, 韧性从70 kJ/m ³提高到313 kJ/m ³, 同时保留了复合薄膜的高电导率(10 ⁴ S/m)和优异的电磁屏蔽性能, 厚度8 μm时可达40 dB以上。