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Carbon nanomaterials, including carbon nanotubes,[1] fullerenes,[2] graphene,[3] and porous carbons,[4] have attracted tremendous attention owing to their unique properties and potential applications, including adsorption, separation, catalysis, gas storage, and electrode materials, among others. More recently, carbon nanomaterials with photoluminescent properties have presented exciting opportunities in the search for benign “nanolanterns” that are highly desired in bioimaging, disease detection, and drug delivery.[5] Compared to organic dyes and fluorescent semiconductor nanocrystals (quantum dots),[6] photoluminescent carbon nanomaterials are superior in chemical inertness and possess distinct benefits, such as no optical blinking, low photobleaching, low cytotoxicity, and excellent biocompatibility.[7] Thus far, numerous approaches, including arc discharge,[8] laser irradiation,[9] electrochemical synthesis,[10] pyrolysis,[11] and hydrothermal [12] methods have been developed to prepare these versatile materials. However, there is still a bottleneck for progress in understanding and controlling the morphology, size, and surface chemistry of the resultant products with high quantum yields (QYs), which impede their practical applications. Moreover, exploration of photoluminescent carbon nanomaterials with high QYs (> 30%), for use as fluorescent chemosensors to monitor and image biological processes, still remains in an early stage.[13] It has been demonstrated that functionalizing fluorescent carbon nanomaterials with nitrogen groups can significantly enhance their properties and expand their novel applications.[14] Despite several …