We report on the control of π-stacking modes (herringbone vs slipped-stack) and photophysical properties of 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene (BP4VA), an anthracene-based organic semiconductor (OSC), by isosteric cocrystallization (i.e., the replacement of one functional group in a coformer with another of "similar" electronic structure) with 2,4,6-trihalophenols (3X-ph-OH, where X = Cl, Br, and I).
View Article and Find Full Text PDFTitanium implants are widely used in dental and orthopedic surgeries. Osseointegration phenomena lead to direct contact between bone tissue and the implant surface. The quality of the bone-implant interface (BII), resulting from the properties of newly formed bone, determines the implant stability.
View Article and Find Full Text PDFBy using complementary DNA sequences as surface ligands, we selectively allow two individual diffusing "dual-color" carbon dots to interact and . Spontaneous nanoscale oxidation of surface-abundant nitroso-/nitro-functionalities leads to two distinctly colored carbon dots (CD) which are isolated by polarity driven chromatographic separation. Green- and red-emitting carbon dots (gCD and rCD) were decorated by complementary single-stranded DNAs which produce a marked increase in the fluorescence emission of the respective carbon dots.
View Article and Find Full Text PDFFor robust single particle optical detection, a high sensitivity in photoluminescence (PL) of Carbon Dots (CDs) must be achieved. PL sensitivity can be successfully correlated with their surface chemistry but requires high synthetic control without altering their basic surface properties. Here we describe conditions for the controlled synthesis of CDs that resulted in a PL sensitivity at the single-particle level.
View Article and Find Full Text PDFSelf-assembly via nanoscale phase separation offers an elegant route to fabricate nanocomposites with physical properties unattainable in single-component systems. One important class of nanocomposites are optical metamaterials which exhibit exotic properties and lead to opportunities for agile control of light propagation. Such metamaterials are typically fabricated via expensive and hard-to-scale top-down processes requiring precise integration of dissimilar materials.
View Article and Find Full Text PDFColloidal quantum dots display a wide range of novel optical properties that could prove useful for many applications in photonics. Here, we report the enhancement of fluorescence emission from colloidal quantum dots on the surface of two-dimensional photonic crystal slabs. The enhancement is due to a combination of high-intensity near fields and strong coherent scattering effects, which we attribute to leaky eigenmodes of the photonic crystal.
View Article and Find Full Text PDFBecause of their potential for use in advanced electronic, nanomechanical, and other applications, large two-dimensional, carbon-rich networks have become an important target to the scientific community. Current methods for the synthesis of these materials have many limitations including lack of molecular-level control and poor diversity. Here, we present a method for the synthesis of two-dimensional carbon nanomaterials synthesized by Mo- and Cu-catalyzed cross-linking of alkyne-containing self-assembled monolayers on SiO(2) and Si(3)N(4).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2006
We developed a class of quasi-3D plasmonic crystal that consists of multilayered, regular arrays of subwavelength metal nanostructures. The complex, highly sensitive structure of the optical transmission spectra of these crystals makes them especially well suited for sensing applications. Coupled with quantitative electrodynamics modeling of their optical response, they enable full multiwavelength spectroscopic detection of molecular binding events with sensitivities that correspond to small fractions of a monolayer.
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