Surface flashover as a well-known discharge phenomenon on the gas–solid interface can lead to the failure of power equipment. Although intensive studies have been devoted to improving the flashover voltage in gases, the perspective on exploiting gas characteristics has so far been ignored. We here directly utilize a polythiourea-assisted coating on epoxy to achieve beneficial gas adsorption and enhance the flashover voltage. The results show that the flashover voltage of the polythiourea-assisted epoxy is significantly improved in both N₂ and SF₆ compared with the blank epoxy. Combining the experimental and computational results, it is proved that the striking improvement in the flashover performance is attributed to the increased gas adsorption quantity resulting from the unique thiourea units in polythiourea. Although both esters in epoxy and thioureas in polythiourea act as active function sites for guest gases, polar thioureas not only lead to pronounced charge displacements but also own the larger density, which further enhances the adsorption energy and promotes the gas adsorption. The resulting increased gas adsorption quantity prevents the collision ionization effectively, thus improving the flashover voltage. Our research innovatively proposes a functional polythiourea-assisted coating that can enhance the flashover voltage by improving the gas adsorption ability.

表面闪络是气固界面上众所周知的放电现象，可导致电力设备发生故障。尽管大量研究致力于提高气体中的闪络电压，但迄今忽略了利用气体特性的观点。我们在这里直接在环氧树脂上使用聚硫脲辅助涂层来实现有益的气体吸附并提高闪络电压。结果表明，聚硫脲辅助环​​氧树脂的闪络电压在N ₂和SF _{6中都有显着提高}与空白环氧树脂相比。结合实验和计算结果，证明闪络性能的显着改善归因于聚硫脲中独特的硫脲单元增加的气体吸附量。虽然环氧树脂中的酯类和聚硫脲中的硫脲都是客体气体的活性功能位点，但极性硫脲不仅会导致明显的电荷位移，而且具有更大的密度，进一步提高吸附能，促进气体吸附。由此增加的气体吸附量有效地阻止了碰撞电离，从而提高了闪络电压。我们的研究创新性地提出了一种功能性聚硫脲辅助涂层，可以通过提高气体吸附能力来提高闪络电压。