5G 电子消费产品日益普及，给人们的生活带来便利的同时也存在一些问题，如电磁干扰 (EMI) 风险大幅度提高，5G 网络耗电速度快等。因此需要开发具有高 EMI 屏蔽性能的膜材料和高容量的电极材料来解决这些问题。作为一种新型二维材料，过渡金属碳化物、氮化物或氮碳化物 (称为 MXene) 具有出色的导电性、低密度、亲水性表面、二维层状形态和可调节的表面化学性质等诸多优势。此外，由于 MXene 具有容易成膜的特点，在 EMI 屏蔽和储能设备等领域具有巨大的应用潜力。目前已经报道了很多基于 MXene 复合薄膜的工作，本文首先介绍了 MXene 纳米片的合成方法，然后讨论了 MXene 基复合薄膜的制备方法，目的是总结制备 MXene 复合薄膜的各种方法及其优缺点。其次，分别介绍了 MXene 在锂离子电池和超级电容器及 EMI 屏蔽膜中的应用，分析了目前的发展趋势，并且对目前主流的复合材料进行了对比，归纳了 MXene复合薄膜在结构和性能上的特点和优势。最后，提出了目前 MXene 复合薄膜的发展所存在的问题，并对未来发展进行了展望。

The increasing popularity of 5G electronic consumer products has brought convenience to people's life, while there are some problems, such as high risk of electromagnetic interference (EMI) and high power consuming of 5G networks. To solve these problems, it is necessary to develop novel materials with high EMI shielding performance and high-capacity electrode materials. As a new two-dimensional (2D) material, transition metal carbides/nitrides (MXene) have excellent conductivity, low density, hydrophilic surface, 2D layer morphology and tunable surface chemistry, etc. MXene shows promising application prospects in EMI shielding and energy storage due to the facile operation for fabricating films. A lot of MXene-based composite films have been reported recently. Thus in this article, we introduced the preparation methods of MXene nanosheets and MXene-based composite films including their advantages and disadvantages. Secondly, we summarized the research progress of MXene in lithium battery, supercapacitor and EMI shielding fields, and concluded the current mainstream composite materials and the characteristics of MXene composite film in structure and performance. Finally, we proposed critical insights on these scientific challenges and potential solutions. Besides, a future perspective on this technology including other challenges was also described.