Hollow nanostructures exhibit a wide range of potential applications because of the quantum confinement effect that arises from the narrow width of such nanostructures. It is challenging to synthesize hollow nanostructures of 2D materials. A facile top‐down approach is presented for synthesizing high‐quality hollow graphene nanostructures from highly oriented pyrolytic graphite target. Hollow graphene nanostructures composed of few‐layered graphene nanorings (GNRs) are synthesized in acetone and poly(4‐vinylpyridine) (P4VP) using the laser ablation in liquid technique. Density functional theory calculations of the layered GNRs indicate that their bandgap converges with an increase in the number of layers. To demonstrate the feasibility of the synthesized NRs for use in device applications, flexible two‐terminal devices with a Pt/GNRs‐P4VP/indium tin oxide structure are fabricated; the devices exhibit excellent memory characteristics, with the ON/OFF ratio being 2 × 10⁴ and the retention time being 10⁵ s. These results suggest that synthesizing uniform bandgap‐engineered GNRs in organic media through laser ablation is an excellent method for realizing high‐density, low‐cost nonvolatile memories in a scalable manner.

中文翻译：

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自上而下的中空石墨烯纳米结构的合成，用于电阻开关存储设备

由于这种纳米结构的窄宽度引起的量子限制效应，中空纳米结构展现出广泛的潜在应用。合成2D材料的空心纳米结构具有挑战性。提出了一种简便的自上而下的方法，用于从高度定向的热解石墨靶合成高质量的中空石墨烯纳米结构。使用液相激光烧蚀技术，在丙酮和聚（4-乙烯基吡啶）（P4VP）中合成了由几层石墨烯纳米环（GNR）组成的空心石墨烯纳米结构。分层GNR的密度泛函理论计算表明，其带隙随着层数的增加而收敛。为了证明合成的NR在设备应用中的可行性，制作了具有Pt / GNRs-P4VP /氧化铟锡结构的柔性双端子设备；该器件具有出色的存储特性，开/关比为2×10⁴，保留时间为10 ⁵ s。这些结果表明，通过激光烧蚀在有机介质中合成均匀带隙工程化的GNR是一种以可扩展的方式实现高密度，低成本非易失性存储器的极佳方法。