| Self-Assembled Functional Nanomaterials | ||
| We are broadly interested in developing new chemical, physical, engineering, and biological applications related to self-assembled nanostructured materials. Our research is highly multidisciplinary: students are educated in a wide range of fields and exposed to a variety of techniques. Brief summations of current projects are listed below Self-Assembled Colloidal Photonic Crystals: Photonic crystals offer unprecedented opportunities for the realization of all-optical integrated circuits and high-speed optical computing. We have recently developed a simple spin-coating technique that combines the simplicity and cost benefits of traditional self-assembly with the scalability and compatibility of nanolithography in creating wafer-scale colloidal photonic crystals with nonclose-packed structures. We currently focus on the fundamental understanding of the shear-induced ordering mechanisms during spin-coating and the photonic band gap properties of self-assembled photonic crystals. |
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| Figure 1: Micropatterned colloidal photonic crystal prepared by spin coating. | ||
| Templated Plasmonic Nanostructures:Surface plasmon-based photonics (or plasmonics) provides another powerful tool for confining, channeling, and amplifying light on the subwavelength scale, enabling highly complex nanooptical circuits. We are investigating the plamonic properties of templated metallic nanostructures, including enhanced optical transmission through metallic nanohole arrays and surface-enhanced Raman scattering (SERS) at nanostructured metallic surfaces. We are also developing new plasmonic nanostructures for targeted drug delivery and hypothermal treatment of cancers. Furthermore, multifunctional nanostructures are being explored for developing efficient OLEDs by combining the directional inhibition and redistribution of light in photonic band gaps with surface-plasmon-enhanced emission. | ||
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| Figure 2: SERS spectra of benzenethiol on a templated Au grating and a featureless Au control sample. | ||
| Biomimetic Antireflection Coatings: Light reflection from flat-panel displays, automobile dashboards, optical elements, and solar cell collectors can impair the legibility of displays by generating “ghost images” and glaring, degrade the quality of optical lens systems, reduce the conversion efficiency of photovoltaincs, and even cause tragic accidents. Inspired by the microstructured cornea of nocturnal moths that can greatly reduce reflection by creating a refractive index gradient across the air/cornea interface, we are developing subwavelength-structured biomimetic antireflection coatings (ARCs). Templated broadband silicon ARCs with self-cleaning functionality have recently been demonstrated by our group. We focus on developing self-cleaning ARCs for improving the light collection efficiencies of crystalline silicon solar cells, which dominate current production of photovoltaics. | ||
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| Figure 3: Templated moth-eye antireflection coating | ||
| Nanocrystalline for Ultra-High Density Magnetic and Optical Recording: Self-organizing ferromagnetic nanocrystalline is promising for ultra-high density magnetic recording materials. Our group is exploring new synthetic and assembly approaches to produce sub-10-nm ferromagnetic nanocrystals and wafer-scale thin-film nanocomposites to target terabits per square inch areal density. We are also interested in developing synthetic strategies for ternary chalcogenide optical recording materials (e.g., GeSbTe and GeBiTe) and investigating their size-dependent structural phase change behavior upon laser irradiation. | ||
© Jiang Group 2007