5 research outputs found
Thermally enhanced photoluminescence and temperature sensing properties of ScWO:Eu phosphors
Currently,lanthanide ions doped luminescence materials applying as optical
thermometers have arose much concern. Basing on the different responses of two
emissions to temperature, the fluorescence intensity ratio (FIR) technique can
be executed and further estimate the sensitivities to assess the optical
thermometry performances. In this study, we introduce different doping
concentrations of Eu ions into negative expansion material
ScWO:Eu, accessing to the thermal enhanced luminescence
from 373 to 548 K, and investigate the temperature sensing properties in
detail. All samples exhibit good thermally enhanced luminescence behavior. The
emission intensity of ScWO: 6 mol% Eu phosphors reaches
at 147.81% of initial intensity at 473 K. As the Eu doping concentration
increases, the resistance of the samples to thermal quenching decreases. The
FIR technique based on the transitions 5D0-7F1 (592 nm) and 5D0-7F2 (613 nm) of
Eu ions demonstrate a maximum relative temperature sensitivity of 3.063%
K-1 at 298 K for ScWO:Eu: 6 mol% Eu phosphors. The
sensitivity of sample decreases with the increase of Eu concentration.
Benefiting from the thermal enhanced luminescence performance and good
temperature sensing properties, the ScWO:Eu: Eu
phosphors can be applies as optical thermometers
Reinforced Self-Assembly of Donor–Acceptor π‑Conjugated Molecules to DNA Templates by Dipole–Dipole Interactions Together with Complementary Hydrogen Bonding Interactions for Biomimetics
One of the most important criteria for the successful
DNA-templated polymerization to generate fully synthetic biomimetic
polymers is to design the complementary structural monomers, which
assemble to the templates strongly and precisely before carrying polymerization.
In this study, water-soluble, laterally thymine-substituted donor–acceptor
Ï€-conjugated molecules were designed and synthesized to self-assemble
with complementary oligoadenines templates, dA<sub>20</sub> and dA<sub>40</sub>, into stable and tubular assemblies through noncovalent
interactions including π–π stacking, dipole–dipole
interactions, and the complementary adenine-thymine (A-T) hydrogen-bonding.
UV–vis, fluorescence, circular dichroism (CD), atomic force
microscopy (AFM), and transmission electron microscopy (TEM) techniques
were used to investigate the formation of highly robust nanofibrous
structures. Our results have demonstrated for the first time that
the dipole–dipole interactions are stronger and useful to reinforce
the assembly of donor–acceptor π-conjugated molecules
to DNA templates and the formation of the stable and robust supramolecular
nanofibrous complexes together with the complementary hydrogen bonding
interactions. This provides an initial step toward DNA-templated polymerization
to create fully synthetic DNA-mimetic polymers for biotechnological
applications. This study also presents an opportunity to precisely
position donor–acceptor type molecules in a controlled manner
and tailor-make advanced materials for various biotechnological applications