With the continuous improvement of in situ techniques inside transmission electron microscope (TEM), the capabilities of TEM extend beyond structurual characterization to high-precision nanofabrication and property measurement. Based on the idea of "setting up a nanolab inside a TEM", we present our recent progress in 2D Materials research including in situ growth, nanofabrication with atomic resolution, in situ property characterization, nanodevice construction and possible applications (e.g. a 5nm-diameter hole on graphene for third-generation gene sequencing, the spongy graphene as an ultra-efficient sorbent for oils and organic solvents, etc.). In addition, reconstructed point defects in graphene are created by electron irradiation and annealing. By applying electron microscopy and density functional theory, it is shown that the strain field around these defects reaches far into the unperturbed hexagonal network and that metal atoms have a high affinity to the non-perfect and strained regions of graphene. The electron irradiation induced trapping of metal atoms in strained areas and at defects in graphene may be used for engineering the local electronic and magnetic structure of graphene which is an alternative to substitutional doping.
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