2 research outputs found
Four-coordinate N-heterocyclic carbene (NHC) copper(I) complexes with brightly luminescence properties
<p>Three four-coordinate N-heterocyclic carbene (NHC) copper(I) complexes, [Cu(Py-Im)(POP)](PF<sub>6</sub>) (<b>P1</b>), [Cu(Py-BenIm)(POP)](PF<sub>6</sub>) (<b>P2</b>), and [Cu(Py-<i>c</i>-BenIm)(POP)](PF<sub>6</sub>) (<b>P3</b>) (Py-Im = 3-methyl-1-(pyridin-2-yl)-1H-imidazolylidene, Py-BenIm = 3-methyl-1-(pyridin-2-yl)-1H-benzo[d]imidazolylidene, Py-<i>c</i>-BenIm = 3-methyl-1-(pyridin-2-ylmethyl)-1H-benzo[d]imidazolylidene, POP = bis([2-diphenylphosphino]-phenyl)ether), have been synthesized without transmetalation of the NHC–Ag(I) complex for the first time. The photophysical properties of the resultant NHC–Cu(I) complexes have been systematically investigated via spectroscopic methods. All complexes exhibit good photoluminescence properties with long excited-state lifetimes and moderate quantum yields. Density functional theory and time dependent density functional theory calculations were employed to rationalize the photophysical properties of the NHC–Cu(I) complexes.</p
Adsorption of Estrogen Contaminants by Graphene Nanomaterials under Natural Organic Matter Preloading: Comparison to Carbon Nanotube, Biochar, and Activated Carbon
Adsorption of two estrogen contaminants
(17β-estradiol and
17α-ethynyl estradiol) by graphene nanomaterials was investigated
and compared to those of a multi-walled carbon nanotube (MWCNT), a
single-walled carbon nanotube (SWCNT), two biochars, a powdered activated
carbon (PAC), and a granular activate carbon (GAC) in ultrapure water
and in the competition of natural organic matter (NOM). Graphene nanomaterials
showed comparable or better adsorption ability than carbon nanotubes
(CNTs), biochars (BCs), and activated carbon (ACs) under NOM preloading.
The competition of NOM decreased the estrogen adsorption by all adsorbents.
However, the impact of NOM on the estrogen adsorption was smaller
on graphenes than CNTs, BCs, and ACs. Moreover, the hydrophobicity
of estrogens also affected the uptake of estrogens. These results
suggested that graphene nanomaterials could be used to removal estrogen
contaminants from water as an alternative adsorbent. Nevertheless,
if transferred to the environment, they would also adsorb estrogen
contaminants, leading to great environmental hazards