Publications by authors named "B D Koivisto"

A theoretical study of the reported photocatalytic systems based on Zr-based MOF (UiO-67) with biphenyl-4,4'-dicarboxylic acid (bpdc) and 2,2'-bipyridine-5,5'-dicarboxylic acid (bpydc) as linkers was performed. Quantum chemical calculations were carried out to understand the optical properties of the materials and to facilitate the rational design of new UiO-67 derivatives with potentially improved features as photocatalysts under ambient conditions. Hence, the effect of the structural modifications on the optical properties was studied considering different designs based on the nature of the linkers: in 1 only the bpdc linker was considered, or the mixture 1 : 1 between bpdc and bpydc linkers (labeled as 1A).

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Electrospinning is a cost-effective and efficient method of producing polymeric nanofibre films. The resulting nanofibres can be produced in a variety of structures, including monoaxial, coaxial (core@shell), and Janus (side-by-side). The resulting fibres can also act as a matrix for various light-harvesting components such as dye molecules, nanoparticles, and quantum dots.

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The optical properties and transduction mechanisms in three reported optical chemosensors based on crown ether with selectivity turn-on luminescence toward Na over K , were investigated using Density Functional Theory/Time-Dependent Density Functional Theory (DFT/TD-DFT). The analysis of the structural stability of the conformers enables us to understand the optical properties of the sensors and their selectivity toward Na . The UV-Vis absorption and the radiative channels of the adiabatic S excited state were assessed.

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near-infrared (NIR) photoacoustic imaging (PAI) studies using novel contrast agents require validation, often fluorescence imaging. Bioconjugation of NIR dyes to proteins is a versatile platform to obtain contrast agents for specific biomedical applications. Nonfluorescent NIR dyes with higher photostability present advantages for quantitative PAI, compared to most fluorescent NIR dyes.

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Article Synopsis
  • A new family of organic dyes inspired by nature was created for use in dye-sensitized solar cells (DSSC), featuring a structure that includes donor and acceptor units.
  • The dyes have two triphenylamine units as donors and two cyanoacetic acid units as acceptors, which attach to a titania semiconductor; the study evaluated the impact of a thiophene π-spacer between the donor units.
  • The performance of the DSSCs was optimized by modifying the distal TPA with different substituents, revealing that fewer π-spacers were more effective and that the interaction of substituents with the electrolyte was crucial for enhancing performance.
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