In an HVDC gas-insulated system, the surface of the insulator accumulates electric charges that distort the surface electric field and reduce the flashover voltage. Therefore, it is crucial to find a material that can effectively suppress the surface charge accumulation. In this work, MXene, a two-dimensional nanomaterial, is doped into an epoxy resin at different concentrations. By doping a small amount of MXene (30ppm), the resistivity of the composite is improved by about 4 times compared to pure epoxy resin. At the same time, the trap level of deep traps increases to 1.07 from 1.04 eV of pure epoxy. Measuring the surface potential of the insulator and using an inversion algorithm to calculate the surface charge establishes that a doping level of 30 ppm of MXene effectively suppresses the accumulation of the surface charge of the insulator, which is only about 1/3 of that of the pure epoxy resin. The surface flashover voltage is also increased by 10%. However, when the doping amount of MXene is increased to 100 or 150 ppm, the insulation performance is lowered. We used a potential barrier model to explain the effect of MXene doping in the epoxy resin. This work presents a possible way to suppress the charge accumulation on the surface of insulators in HVDC gas-insulated systems and provides a link between the microstructure and the macroscopic properties in the material.

中文翻译：

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MXene掺杂环氧树脂抑制直流气体绝缘系统绝缘体表面电荷积累

在 HVDC 气体绝缘系统中，绝缘体表面会积累电荷，从而扭曲表面电场并降低闪络电压。因此，寻找一种能够有效抑制表面电荷积累的材料至关重要。在这项工作中，将二维纳米材料 MXene 以不同浓度掺杂到环氧树脂中。通过掺杂少量MXene（30ppm），复合材料的电阻率比纯环氧树脂提高了约4倍。同时，深陷阱的陷阱能级从纯环氧树脂的 1.04 eV 增加到 1.07。测量绝缘体的表面电位并使用反演算法来计算表面电荷确定 30 ppm 的 MXene 掺杂水平有效地抑制了绝缘体表面电荷的积累，仅为纯环氧树脂的1/3左右。表面闪络电压也提高了10%。然而，当MXene的掺杂量增加到100或150ppm时，绝缘性能会降低。我们使用势垒模型来解释 MXene 在环氧树脂中掺杂的影响。这项工作提出了一种可能的方法来抑制 HVDC 气体绝缘系统中绝缘体表面的电荷积累，并提供了材料的微观结构和宏观特性之间的联系。