Kyueui Lee

Direct Insulation‐to‐Conduction Transformation of Adhesive Catecholamine for Simultaneous Increases of Electrical Conductivity and Mechanical Strength of CNT Fibers

Increase in conductivity and mechanical properties of a carbon nanotube (CNT) fiber inspired by mussel-adhesion chemistry is described. Infiltration of polydopamine into an as-drawn CNT fiber followed by pyrolysis results in a direct insulation-to-conduction transformation of poly(dopamine) into pyrolyzed-poly(dopamine) (py-PDA), retaining the intrinsic adhesive function of catecholamine. The py-PDA enhances both the electrical conductivity and the mechanical strength of the CNT fibers.

Facile method to sort graphene quantum dots by size through ammonium sulfate addition

We report a method to purify graphene quantum dots size simply by adding ammonium sulfate. The addition of a salt to a heterogeneous GQD suspension results into the sorting of GQD sub-populations with diameters corresponding to 2.7 ± 1.6, 5.1 ± 1.5, 13.3 ± 1.9, and 18.7 ± 4.4 nm. These GQDs also exhibit different optical properties.

Progress in internal/external stimuli responsive fluorescent carbon nanoparticles for theranostic and sensing applications

In the past decade, fluorescent carbon nanoparticles (FNPs) prepared from natural resources and biomaterials have been attractive due to their various properties, such as unique optical properties, great biocompatibility, water dispersion, and facile surface functionalization. Depending on the properties of the carbon sources and the subsequent carbonization processes, internal/external stimuli responsive carbon nanoparticles have been generated that are useful for theranostic and sensing applications. In this review, we highlight the recent developments in the use of FNPs in nanomedicine in great detail, particularly for FNPs responding to internal stimuli, including redox, pH, and enzymes, and external stimuli, including temperature, light, and magnetic fields, for drug delivery and sensing applications. Furthermore, we hope to provide insight that could stimulate further research aiming for unparalleled useful applications. As a result, there are many possibilities that can be explored from this smart material.