Porous, atomically thin graphene membranes have interesting properties for filtration and sieving applications. Here, graphene membranes are used to pump gases through nanopores using optothermal forces, enabling the study of gas flow through nanopores at frequencies above 100 kHz. At these frequencies, the motion of graphene is closely linked to the dynamic gas flow through the nanopore and can thus be used to study gas permeation at the nanoscale. By monitoring the time delay between the actuation force and the membrane mechanical motion, the permeation time-constants of various gases through pores with diameters from 10–400 nm are shown to be significantly different. Thus, a method is presented for differentiating gases based on their molecular mass and for studying gas flow mechanisms. The presented microscopic effusion-based gas sensing methodology provides a nanomechanical alternative for large-scale mass-spectrometry and optical spectrometry based gas characterisation methods.

多孔，原子薄的石墨烯膜对于过滤和筛分应用具有令人感兴趣的特性。在这里，石墨烯膜用于利用光热力将气体泵送通过纳米孔，从而能够研究高于100 kHz频率的气体通过纳米孔的情况。在这些频率下，石墨烯的运动与通过纳米孔的动态气流紧密相关，因此可以用于研究纳米级的气体渗透。通过监测驱动力和膜机械运动之间的时间延迟，各种气体通过直径为10-400 nm的孔的渗透时间常数显示出显着不同。因此，提出了一种基于分子质量区分气体并研究气体流动机理的方法。