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  1. A new N-alkynylated dithieno[3,2- b :2′,3′- d ]pyrrole (DTP) monomer was synthesized using a Buchwald–Hartwig amination of 3,3′-dibromo-2,2′-bithiophene with pent-4-yn-1-amine. The obtained monomer was investigated for the possibility of a pre-polymerization modification via Huisgen 1,3-dipolar cycloaddition (“click”) reaction with azide-containing organic compounds. The synthesized N-alkynylated DTP monomer is soluble in a number of organic solvents and reacts with organic azides via “click” reactions in mild conditions, achieving high yields. The N-alkynylated DTP monomer and its “click”-modified derivative can be electropolymerized to form polymeric films. Herein, the synthesis and characterization of a “click” modified DTP monomer, its pre-modified derivative, and their corresponding polymers are described. The developed method is a facile route to synthesize a new generation of various N-functionalized DTP homopolymers.
    Free, publicly-accessible full text available October 11, 2023
  2. A series of multi-doped yttrium pyrosilicate (YPS) nanoparticles were synthesized using a high temperature multi-composite reactor, and used to explore the radioluminescent properties that have potential for biological applications. The luminescent activators explored in this work were cerium, terbium, and europium. A series of mono-doped YPS nanoparticles were synthesized that have optical and X-ray luminescent properties that span the entire visible spectrum. Energy transfer experiments were investiagted to increase the photo- and X-ray luminescence of terbium and europium. Cerium was used as a sensitizer for terbium where X-ray luminescence was enhanced. Similar results were also obtained using cerium as a sensitizer and terbium as an energy bridge for europium. By leveraging different energy transfer mechanisms X-ray luminescence can be enhanced for YPS nanoparticles.
  3. null (Ed.)
    As the most likely prospect for the construction of neuromorphic networks, the emulation of synaptic responses with memristors has attracted attention in both the microelectronic industries and the academic environment. To that end, a newly synthesized hybrid conjugated polymer with pendant carbazole rings, that is, poly(4-(6-(9 H -carbazol-9-yl)hexyl)-4 H -dithieno[3,2- b :2′,3′- d ]pyrrole) (pC6DTP), was employed in the fabrication of a two-terminal memristor with a Al/pC6DTP/ITO configuration where the polymer was electrochemically doped. Signature biological synaptic responses to voltage spikes were demonstrated, such as potentiation & depression and spike timing dependent plasticity. The device was able to be programed through a 1 mV pulse, requiring only 100 fJ of energy. The voltage-dependent conductive nature of the polymer was speculated to occur through two synergistic mechanisms, one associated with the conjugation along the backbone of the conjugated polymer and one mechanism associated with the pendant heterocyclic rings.
  4. X-ray active, terpolymer nanospheres are fabricated by copolymerizing styrene, propargyl acrylate, and anthracene methyl methacrylate. The strong Coulombic forces between particles induce spontaneous self-assembly into a crystalline colloidal array.

  5. An organic, x-ray radioluminescent colloid is fabricated by copolymerizing an organic scintillating monomer within a polystyrene basis. The intensity of emitted light from the radioluminescent colloidal particles can be manipulated by photonic means.

  6. Conjugated electrochemical memristors are a promising alternative towards bioelectronic circuitry. A self-doped PEDOT is synthesized, fabricated as a three-terminal device, and studied for electrochromic, memristive, and neuromorphic capabilities.
  7. Radioluminescent copolymer nanoparticles that self-assembled into a crystalline colloidal array due to electrostatic repulsion were encapsulated within hydrogels. The rejection wavelength of the gels was tuned through drying and swelling the system.

  8. Due to Coulombic forces, X-ray active copolymer nanoparticles self-assembled into crystalline colloidal arrays which were stabilized through encapsulation in hydrogels. The system was able to emit blue light when pumped with an X-ray source.
  9. Core/shell nanoparticles composed of a silica core over which a propargyl methacrylate (PMA) shell was polymerized around were synthesized. To employ the shell coating, the surface of the silica nanoparticles (SiNPs) was modified with an alkene-terminated organometallic silane linker that allowed for the covalent attachment of a poly(propargyl methacrylate) (pPMA) shell. The alkyne groups resulting from the pPMA shell were utilized in copper(I)-catalyzed azide/alkyne cycloaddition (CuAAC) reactions to attach azide-modified Förster resonance energy transfer (FRET) pairs of naphthalimide (azNap), rhodamine B (azRhod), and silicon phthalocyanine (azSiPc) derivatives to the shell surface. The luminescence of the system was manipulated by the covalent attachment of one, two, or three of the fluorophores resulting in no energy transfer, one energy transfer, or two energy transfers, respectively. When all three fluorophores were attached to the core/shell particles, an excitation of azNap with a wavelength of 400 nm resulted in the sequential energy transfer between two FRET pairs and the sole emission of azSiPc at 670 nm. These particles may have applications as bioimaging probes as their luminescence is easily detected using fluorescence microscopy.