Polybenzimidazole copolymer derived lacey carbon film for graphene transfer and contamination removal strategies for imaging graphene nanopores

The study of the nanometer-scale vacancy defects (nanopores) in graphene by transmission electron microscopy (TEM) is severely hindered presence polymeric residues originating from graphene-transfer-step to TEM grid. state-of-the-art transfer strategies yield contamination-free pristine specimens but do not work well for nanoporous graphene. This because relatively high energy vacant nanopores which makes it difficult remove without altering structure Herein, we present a novel strategy fabricate sub-100-nm-thick lacey polymer film hosting see-through windows (10–900 nm) using facile nonsolvent-induced phase separation (NIPS). transformed into carbon that reinforces and allows residue-free grid as one avoids direct contact between within window. Finally, atmospheric-, graphene-synthesis-, transfer-bath-related contaminants are removed annealing specimen inside an activated bed at 900 °C reducing atmosphere. method results samples with large areas easy find during aberration-corrected high-resolution (AC-HRTEM) imaging, enabling throughput structural analysis nanopores.