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Abstract We present a versatile platform for fabricating two‐photon excitable carbon dot‐based nanocomposite thin films by harnessing the structural versatility of polymer brushes in combination with electron‐beam lithography (EBL). This approach enables the precise spatial organization of carbon dots (CDs) at the nanoscale, facilitating dynamic modulation of their photoluminescent properties in response to environmental stimuli. Three model systems were examined, incorporating pH‐ and thermally responsive polymers, functionalized through covalent and dynamic covalent bonding strategies. By leveraging the spatial control afforded by nanostructured polymer brushes, we achieved precise tuning of optical properties while mitigating aggregation‐induced quenching, a longstanding challenge in solid‐state CD applications. In addition to the advances in controlling optical properties, this work highlights the potential of polymer brush systems to function as optically active, reprogrammable surfaces. The resulting nanoscale‐engineered materials exhibit highly responsive, reconfigurable photonic behavior, offering a scalable pathway for integrating advanced optical interfaces into microchip technologies, biosensing platforms, and multiplexed diagnostic systems. The fusion of polymer brushes, carbon dots, and advanced lithographic techniques marks a substantial advancement in the development of functional materials with nanoscale precision and stimuli‐responsive properties. 

Abstract Hypergolic reactions have emerged as a new synthetic approach enabling the rapid production of a diverse set of materials at ambient conditions. While hypergolic reactions bear several similarities to the well-established flame spray pyrolysis (FSP), the former has only recently been demonstrated as a viable approach to materials synthesis. Here we demonstrate a new pathway to 2D materials using hypergolic reactions and expand the gallery of nanomaterials synthesized hypergolically. More specifically, we demonstrate that ammonia borane complex, NH₃BH₃, or 4-fluoroaniline can react hypergolically with fuming nitric acid to form hexagonal boron nitride/fluorinated carbon nanosheets, respectively. Structural and chemical features were confirmed with x-ray diffraction, infrared, Raman, XPS spectroscopies and N₂porosimetry measurements. Electron microscopy (SEM and TEM) along with atomic force microscopy (AFM) were used to characterize the morphology of the materials. Finally, we applied Hansen affinity parameters to quantify the surface/interfacial properties using their dispersibility in solvents. Of the solvents tested, ethylene glycol and ethanol exhibited the most stable dispersions of hexagonal boron nitride (h-BN). With respect to fluorinated carbon (FC) nanosheets, the suitable solvents for high stability dispersions were dimethylsulfoxide and 2-propanol. The dispersibility was quantified in terms of Hansen affinity parameters (δ_d,δ_p,δ_h) = (16.6, 8.2, 21.3) and (17.4, 10.1, 14.5) MPa^1/2for h-BN and FC, respectively.