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We have synthesized a co-condensed hollow ethane-bipyridine periodic mesoporous organosilica (HEt-bpy-PMO) as a host material to anchor lanthanides for the purpose of developing a multifunctional chemical sensor. The host material was grafted with lanthanide chloride salts or complexes. The luminescence properties of the developed series of hybrid materials were studied in detail in the solid-state and after dispersing in water. The Eu3+ or Tb3+ singly incorporated materials were investigated for their use as ion sensors, showing ions selectivity towards Cu2+, Co2+ and Fe3+. Additionally, the Eu3+ or Tb3+ incorporated materials showed obvious luminescence quenching behavior towards acetone compared to other organic solvents, indicating excellent acetone sensing selectivity. [ABSTRACT FROM AUTHOR]

Lanthanide hydrogen-bonded organic frameworks (LnHOFs) are recently emerging as a novel versatile class of multicomponent luminescent materials with promising potential applications in optics and photonics. Trivalent europium (Eu3+) incorporated polymeric hydrogen-bonded triazine frameworks (PHTF:Eu) have been successfully obtained via a facile and low-cost thermal pyrolysis route. The PHTF:Eu material shows a porous frame structure principally composed of isocyanuric acid and ammelide as a minor constituent. Intense red luminescence with high colour-purity from Eu3+ is obtained by exciting over a broad absorption band peaked at 300 nm either at room or low temperature. The triazine-based host works as excellent optical antenna towards Eu3+, yielding ~42% sensitization efficiency (ηsens) and an intrinsic quantum yield of Eu3+ emission (ΦEu) as high as ~46%. Temperature-dependent emission studies show that PHTF:Eu displays relatively high optical stability at elevated temperatures in comparison to traditional inorganic phosphors. The retrieved activation energy of 89 meV indicates that thermal quenching mechanisms are attributed to the intrinsic energy level structure of the metal-triazine assembly, possibly via a thermally activated back transfer to ligand triplet or CT states. Finally, by using an innovative approach based on excitation spectra, we demonstrate that PHTF:Eu can work as a universal primary self-referencing thermometer based on a single-emitting center with excellent relative sensitivity in the cryogenic temperature range. [ABSTRACT FROM AUTHOR]

Under exceptional circumstances, light and molecules bond together, creating new hybrid light–matter states with far-reaching consequences for these strongly coupled entities. The present article describes the quantum-mechanical foundation of strong-coupling and experimental evidence for molding the radiation properties of nanoprobes by strong-coupling. When applied to tracing and marking, the new fluorometry technique proposed here, which harnesses strong-coupling, has a triple advantage compared to its classical counterparts such as DNA tracing. It is fast, and its signal-to-noise ratio can be improved by spectral filtering; moreover, it reveals a specific quantum signature of the strong-coupling, which is extremely difficult to reproduce classically, thereby opening the door to new anti-counterfeiting strategies. [ABSTRACT FROM AUTHOR]

Here, three unique organic–inorganic hybrid nanocomposite materials prepared by combining NaYF4:Yb3+,Ln3+ (Ln3+ = Er3+, Tm3+, Ho3+) and periodic mesoporous organosilica (PMO) are proposed for both metal ion sensing and solvent sensing. The luminescence properties of the developed hybrid materials, PMO@NaYF4:Yb3+,Ln3+, were studied in detail in the solid state and after dispersing in water. It is found that PMO@NaYF4:Yb3+,Er3+ showed selective "turn on" luminescence for Hg2+ with the detection limit of 24.4 μM in an aqueous solution. Additionally, the above three materials showed different luminescence emission responses towards water and organic solvents. It is worth noting that all three PMO@NaYF4:Yb3+,Ln3+ materials showed "turn on" luminescence towards alcohols. PMO@NaYF4:Yb3+,Er3+ and PMO@NaYF4:Yb3+,Ho3+ were selected and further developed into sensitive sensors for the detection of water in alcohols by taking advantage of their quenching behavior in water. The detection limit for sensing of water was determined to be 0.21%, 0.18% and 0.29%, corresponding to isopropanol (PMO@NaYF4:Yb3+,Er3+), n-butanol (PMO@NaYF4:Yb3+,Er3+) and ethanol (PMO@NaYF4:Yb3+,Ho3+), respectively. The above results illustrate the potential of these hybrid materials for applications in environmental fields as well as in chemical industries. [ABSTRACT FROM AUTHOR]

Uranyl complex dissolved in room-temperature ionic liquids has diagnostic absorption and emission spectra that has allowed the identification of the symmetry and geometry of the complex. The uranyl complexes are examined in imidazolium and pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids.

Near‐infrared persistent luminescent materials have great potential for in vivo bioimaging and night‐vision surveillance due to their long‐lasting autofluorescence‐free emission through deep tissues and multicycle photostimulated luminescence by releasing energy from captured traps using high‐intensity 808 or 980 nm lasers. However, phosphors combining both near‐infrared persistent luminescence and photostimulated luminescence are found mostly in chromium doped gallates hosts, other emitters are rarely reported. Herein, a new material system with near‐infrared persistent luminescence is achieved in tetravalent manganese doped double‐perovskite alkali‐earth metal tungstates via the aliovalent substitution of calcium ions with lanthanum ions. Persistent luminescence can be generated via X‐ray irradiation, providing great promise in long‐term deep‐tissue ultrasensitive imaging, information storage, and X‐ray detection. Photostimulated detrapping is successfully demonstrated using a common 420 nm light emitting diode instead of a high‐intensity 808 or 980 nm laser. The traps distribution is proved to be reshuffled upon this laser‐free visible light stimulation. Reshuffling of trap distributions upon visible light stimulation may be promising for optical information storage applications. This work is expected to broaden the range of near‐infrared persistent material systems and provides new insights into manipulating photostimulated traps via laser‐free light stimulation. [ABSTRACT FROM AUTHOR]

Panchromatic single-component pure white light generation with a PLQY of ∼14.5% is obtained from a dysprosium complex with the 5,7-dichloro-8-quinolinol ligand (HClQ) thanks to a peculiar orange-red excimer-like emission induced by π-staking interactions between discrete dimeric units in the crystal packing. The emission color is highly tunable by phase change and mechanical stimuli. Remarkably, this compound also displays Dy-centered NIR emission at telecommunication wavelengths upon photoexcitation over an extraordinarily broad spectral range. [ABSTRACT FROM AUTHOR]