The first results of high-speed atomic oxygen (AO) irradiation tests for atomically thin single-layer graphene sheets are presented as space environmental tolerance evaluation tests toward application in astronomy. The single-layer graphene sample was prepared without a metal coating, and high-speed AO irradiation tests were conducted with an averaged velocity of ∼6 km/s using a laser-detonation AO beam source assuming a low Earth orbit (LEO) case. The Raman spectral features were examined before and after the tests with fluence values of 2×1015, 2×1016, 2×1017, 2×1018, and 2×1019 atoms/cm2. It was found that there is no significant change in the observed D/G ratios for fluence up to 2×1017 atoms/cm2. In contrast, the D/G ratios changed from 0.04±0.03 to 0.8±0.4 for 2×1018 atoms/cm2 drastically in both the averaged value and 1-sigma range. Furthermore, the D/G ratio could not be measured beyond 2×1019atoms/cm2 because no peaks were observed in both the G and D bands, which suggests that the degradation occurs between 2×1017 and 2×1018 atoms/cm2 and no graphene sheets exist after the 2×1019 atoms/cm2 irradiation. Scanning electron microscopy images also support this conclusion in terms of the observed image contrast. Consequently, to protect the single-layer graphene sheets from erosion, a special treatment such as coating is needed to survive in an LEO for ≳ a day.

中文翻译：

---

原子薄石墨烯的高速原子氧辐照用于天文应用


原子薄单层石墨烯片的高速原子氧（AO）辐照测试的第一个结果作为天文学应用的空间环境耐受性评估测试提出。在没有金属涂层的情况下制备单层石墨烯样品，并假设低地球轨道（LEO）情况下使用激光爆轰AO光束源以平均速度~6 km/s进行高速AO辐照测试。测试前后的拉曼光谱特征分别为2×1015、2×1016、2×1017、2×1018、2×1019atoms/cm2。结果发现，注量高达 2×1017 个原子/cm2 时，观察到的 D/G 比率没有显着变化。相比之下，对于 2×1018 原子/cm2，D/G 比率在平均值和 1-sigma 范围内都从 0.04±0.03 急剧变化到 0.8±0.4。此外，D/G 比无法测量超过 2×1019atoms/cm2，因为在 G 和 D 带中均未观察到峰值，这表明降解发生在 2×1017 和 2×1018atoms/cm2 之间，并且没有石墨烯2×1019原子/cm2照射后存在片状。扫描电子显微镜图像在观察到的图像对比度方面也支持这一结论。因此，为了保护单层石墨烯片免受侵蚀，需要进行涂层等特殊处理，才能在近地轨道中存活≳一天。