论文标题
通过受控的电化学蚀刻来轻松和超清洁石墨烯玻璃纳米孔
Facile and Ultraclean Graphene-on-Glass Nanopores by Controlled Electrochemical Etching
论文作者
论文摘要
已经探索了各种方法,以应对石墨烯纳米结构的挑战,所有方法都需要复杂而高端的纳米化平台,并遭受表面污染的困扰,可能会产生电噪声并增加原子薄石墨烯膜的厚度。在这里,通过在低电容石墨烯(GOG)膜上使用电脉冲,我们在具有异常低的电噪声的市售玻璃基板上制造了干净的石墨烯纳米孔。原位液体AFM研究和电化学测量结果表明,石墨烯纳米孔成核和生长均源自对缺陷部位对碳原子的电化学攻击,从而确保了石墨烯纳米孔的产生。令人惊讶的是,与传统的TEM钻石纳米孔相比,GOG纳米孔具有刻度降低的宽带噪声,我们将其归因于机械稳定的玻璃芯片上的石墨烯纳米孔的电化学刷新,并具有可忽略的寄生虫能力(1 pf)。对双链DNA易位的进一步实验表明,电流噪声大大降低,并且也证实了单纳米孔的激活。因此,极低的噪声和易于制造的易用性将有助于理解基本特性和这种原子较薄的纳米孔传感器的应用。
A wide range of approaches have been explored to meet the challenges of graphene nanostructure fabrication, all requiring complex and high-end nanofabrication platform and suffering from surface contaminations, potentially giving electrical noise and increasing the thickness of the atomically thin graphene membrane. Here, with the use of an electrical pulse on a low capacitance graphene-on-glass (GOG) membrane, we fabricated clean graphene nanopores on commercially available glass substrates with exceptionally low electrical noise. In situ liquid AFM studies and electrochemical measurements revealed that both graphene nanopore nucleation and growth stem from the electrochemical attack on carbon atoms at defect sites, ensuring the creation of a graphene nanopore. Strikingly, compared to conventional TEM drilled graphene nanopores on SiN supporting membranes, GOG nanopores featured an order-of-magnitude reduced broadband noise, which we ascribed to the electrochemical refreshing of graphene nanopore on mechanically stable glass chips with negligible parasitic capacitance (1 pF). Further experiments on double-stranded DNA translocations demonstrated a greatly reduced current noise, and also confirmed the activation of single nanopores. Therefore, the exceptionally low noise and ease of fabrication will facilitate the understanding of the fundamental property and the application of such atomically thin nanopore sensors.