Publications by authors named "Sujin R Lee"

Anisotropic stimuli-responsive microgels based upon the cholesteric phase of chitin nanocrystals and -isopropylacrylamide were designed and synthesized. The cholesteric structure was interrogated, and the texture was shown to directly influence the microgel shape and anisotropy. Changes in the microgel volume led to changes in the texture, where microgels comprising up to six bands exhibited a twisted bipolar texture, while those with greater volumes displayed a concentric-packing structure.

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Conjugated polymers possessing polar functionalities were shown to effectively anchor single-walled carbon nanotubes (SWNTs) to the surface of high-capacity anode materials and enable the formation of electrical networks. Specifically, poly[3-(potassium-4-butanoate) thiophene] (PPBT) served as a bridge between SWNT networks and various anode materials, including monodispersed FeO spheres (sFeO) and silicon nanoparticles (Si NPs). The PPBT π-conjugated backbone and carboxylate (COO-) substituted alkyl side chains, respectively, attracted the SWNT π-electron surface and chemically interacted with active material surface hydroxyl (-OH) species to form a carboxylate bond.

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A carbon nanotube (CNT) web electrode comprising magnetite spheres and few-walled carbon nanotubes (FWNTs) linked by the carboxylated conjugated polymer, poly[3-(potassium-4-butanoate) thiophene] (PPBT), was designed to demonstrate benefits derived from the rational consideration of electron/ion transport coupled with the surface chemistry of the electrode materials components. To maximize transport properties, the approach introduces monodispersed spherical FeO (sFeO) for uniform Li diffusion and a FWNT web electrode frame that affords characteristics of long-ranged electronic pathways and porous networks. The sFeO particles were used as a model high-capacity energy active material, owing to their well-defined chemistry with surface hydroxyl (-OH) functionalities that provide for facile detection of molecular interactions.

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