4 research outputs found
Structure of the FeBTC Metal–Organic Framework: A Model Based on the Local Environment Study
The local environment of iron in
FeBTC, a metal organic framework
commercially known as Basolite F300, is investigated combining XANES
and EXAFS studies of the iron K-edge. The building block of the FeBTC
can be described as an iron acetate moiety. Dehydration induces a
change in the coordination of the first shell while preserving the
network. We propose that the local structure around Fe atoms does
not undergo a rearrangement, thus, leading to the formation of an
open site. The analysis conveys that the FeBTC is a disordered network
of locally ordered blocks
Shifting Demand for Non Medical Services Evaluation Report
This evaluation looked at the feasibility and utility of a city-wide, brief intervention provided by community support workers to link people with non-medical issues to a range of services and support. The GP referral system effectively identified people at high risk of avoidable hospital admissions. Over 90% of patients referred received an assessment from a community support worker (CSW). The approach used by CSWs was consistent with the international evidence base for providing effective peer support. Clients initially self-reported reduced anxiety and social isolation. After being linked, however, there were delays in getting needs met, leading to disengagement and return to the high risk group. Effectiveness of the service is dependent upon the capacity and responsiveness of the sectors to which clients are referred.<br
β‑C<sub>3</sub>N<sub>4</sub> Nanocrystals: Carbon Dots with Extraordinary Morphological, Structural, and Optical Homogeneity
Carbon
nanodots are known for their appealing optical properties,
especially their intense fluorescence tunable in the visible range.
However, they are often affected by considerable issues of optical
and structural heterogeneity, which limit their optical performance
and limit the practical possibility of applying these nanoparticles
in several fields. Here we developed a synthesis method capable of
producing a unique variety of carbon nanodots displaying an extremely
high visible absorption strength (ε > 3 × 10<sup>6</sup> MÂ(dot)<sup>−1</sup> cm<sup>–1</sup>) and a high fluorescence
quantum yield (73%). The high homogeneity of these dots reflects in
many domains: morphological (narrow size distribution), structural
(quasi-perfect nanocrystals with large electronic bandgaps), and optical
(nontunable fluorescence from a single electronic transition). Moreover,
we provide the proof of principle that an aqueous solution of these
dots can be used as an active medium in a laser cavity, displaying
a very efficient laser emission with dye-like characteristics, which
reflects the benefits of such a highly homogeneous type of carbon-based
nanodots
Porous Magneto-Fluorescent Superparticles by Rapid Emulsion Densification
Porous superstructures are characterized by a large surface
area
and efficient molecular transport. Although methods aimed at generating
porous superstructures from nanocrystals exist, current state-of-the-art
strategies are limited to single-component nanocrystal dispersions.
More importantly, such processes afford little control over the size
and shape of the pores. Here, we present a new strategy for the nanofabrication
of porous magneto-fluorescent nanocrystal superparticles that are
well controlled in size and shape. We synthesize these composite superparticles
by confining semiconductor and superparamagnetic nanocrystals within
oil-in-water droplets generated using microfluidics. The rapid densification
of these droplets yields spherical, monodisperse, and porous nanocrystal
superparticles. Molecular simulations reveal that the formation of
pores throughout the superparticles is linked to repulsion between
nanocrystals of different compositions, leading to phase separation
during self-assembly. We confirm the presence of nanocrystal phase
separation at the single superparticle level by analyzing the changes
in the optical and photonic properties of the superstructures as a
function of nanocrystal composition. This excellent agreement between
experiments and simulations allows us to develop a theory that predicts
superparticle porosity from experimentally tunable physical parameters,
such as nanocrystal size ratio, stoichiometry, and droplet densification
rate. Our combined theoretical, computational, and experimental findings
provide a blueprint for designing porous, multifunctional superparticles
with immediate applications in catalytic, electrochemical, sensing,
and cargo delivery applications