In this paper, we present an electrostatic self-assembly method for the controlled placement of individual nanoparticle emitters based on reusable inorganic templates. This method can be used to integrate quantum emitters into nanophotonic structures over macroscopic areas and is applicable to a variety of patterning materials and emitter systems. By utilizing surface-charge-mediated self-assembly, highly ordered arrays of nanoparticle emitters were created. To illustrate the broad applicability of this technique, we demonstrate self-assembly using colloidal quantum dots (QD), nitrogen vacancy (NV) centers in diamond nanoparticles, and lanthanide-doped upconversion nanoparticles (UCNP). Placement of single QDs and NV centers was confirmed by performing photon antibunching measurements using a Hanbury-Brown Twiss setup. In addition, template reusability was demonstrated through daily redeposition experiments over a one month period.
Exploiting near-infrared
(NIR) light responsive photocatalysts
is especially significant for effective use of solar energy. Enhancing
the luminescence of upconversion (UC) photocatalysts is particularly
important for the development of NIR-driven photocatalysts. Here,
Yb3+/Er3+/Ho3+ triple-doped BiOBr
nanosheets were synthesized by solvothermal method. The UC luminescence
and NIR photocatalytic activity of BiOBr:Yb3+/Er3+/Ho3+ nanosheets can be optimized by tuning the Ho3+ doping concentrations. Results indicated that the green
UC emission intensity of BiOBr:Yb3+/Er3+/0.5%Ho3+(BYE-0.5Ho) was improved by about 4.2 times that of BiOBr:Yb3+/Er3+(BYE-0Ho). Based on the UC spectra and lifetime
decay curves, the energy transfer of Er3+ → Ho3+ was the main factor responsible for the enhanced green UC
luminescence. As expected, the BYE-0.5Ho demonstrated superior photocatalytic
performance in degrading RhB under NIR light irradiation, which was
1.53 times higher than that of BYE-0Ho. Moreover, this superior photoactivity
can achieve the degradation of MB and BPA, verifying the universal
applicability of BiOBr:Yb3+/Er3+/Ho3+ nanosheets. In depth investigations confirmed that the improving
activity can be ascribed to enhanced green UC luminescence and improved
the separation efficiency of the electron–hole pairs through
doping Ho3+ ions, as evidenced by photoluminescence and
electrochemical analyses. This work provides an effective way of enhancing
NIR photocatalytic performance, which will be conducive to making
full use of solar energy in the future.
13 Cobalt-free perovskite-type mixed ionic and electronic conductor (MIEC) is of 14 technological and economic importance in many energy related applications. In this work, a new 15 group of Fe-based perovskite MIEC with BaFe 1-x Gd x O 3-δ (0.025≤x≤0.20) compositions was 16 developed for the application in oxygen permeation membrane. Slight Gd doping (x=0.025) can 17 stabilize the cubic structure of BaFe 1-x Gd x O 3-δ perovskite. The Gd substitution of BaFe 1-x Gd x O 3-δ 18 materials increases the structural and chemical stability in atmosphere containing CO 2 and H 2 O, 19and decreases the thermal expansion coefficient. The BaFe 0.975 Gd 0.025 O 3-δ membrane exhibits fast 20 oxygen surface exchange kinetics and high bulk diffusion coefficient, and achieves a high oxygen 21 2 permeation flux of 1.37 mL cm -2 min -1 for 1 mm thick membrane at 950 o C under Air/He oxygen 1 gradient, which can maintain stable at 900 o C for 100 h. Compared to the pristine BaFeO 3-δ and the 2 well-studied Ba 0.95 La 0.05 FeO 3-δ membranes, lower oxygen permeation activation energy and higher 3 oxygen permeability are obtained for the 2.5 at. % Gd doped material, which might be attributed to 4 the expanded lattice by doping large Gd 3+ cations and limited negative effect from strong Gd-O 5 bond. A combination study of first principle calculation and experimental measurements was 6 further conducted to advance the understanding of Gd effects on oxygen migration behavior in 7BaFe 1-x Gd x O 3-δ . These findings are expected to provide guidelines for the material design of high 8 performance MIECs. 9
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.