Three new rhodamine-based probes Y1-Y3 were synthesized as "off-on" chemosensors for Fe(3+) imaging in living cells. The recognizing behaviors were investigated both experimentally and computationally. The crystal structure of the complex Y3-Fe(3+) revealed that Fe(3+) preferred to coordinate with the N atom of benzothiazole moiety rather than the O atom of carboxyl group.

The Suzuki-Miyaura coupling of aryl nitriles with aryl/alkenyl boronic esters is reported. With this method, the cyano group could be applied as a protecting group of arenes and finally as a leaving group to further construct polyaryl scaffolds.

An optical temperature sensor and optical heater based on Yb3+/Tm3+ co-doped Ba5Gd8Zn4O21 phosphors.

Ce3+/Pr3+ codoped Li2SrSiO4 (LSS) phosphors with blue, red, and near‐infrared (NIR) tri‐emission have been prepared via a high‐temperature solid‐state reaction method. Under the excitation of 200 to 400 nm near‐ultraviolet (n‐UV), the photoluminescence (PL) spectra of phosphors are composed of visible and NIR two parts. The former exhibits blue and red emission bands centered at around 428 nm from 5d–4f transition of Ce3+ and 611 nm from 1D2 → 3H4 transition of Pr3+, those overlap with photosynthesis action spectra of plants and absorption spectra of chlorophylls and carotenoids. While the later presents a broad NIR emission band peaking near 1039 nm caused by the 1G4 → 3H4 of Pr3+, matching with the absorption of bacteriochlorophyll. Their emission intensity ratios (B: R: NIR) could be tuned by altering the relative ratios of Ce3+ and Pr3+ concentration in the phosphors to meet the requirements of multifarious plants and bacteria. The efficient energy transfer from Ce3+ to Pr3+ takes place in the LSS host, which ascribed to an exchange interaction according to PL spectra and decay curves of phosphors. Results suggest that the present LSS: Ce3+, Pr3+ phosphors have great potential applications in plant growth n‐UV LED.

Ce 3+ -doped Ba 2 Ln(BO 3 ) 2 Cl (Ln ¼ Gd, Y) phosphors were synthesized through a conventional hightemperature solid state method in CO atmosphere. Structural and spectroscopic characterizations of the samples have been performed by X-ray diffraction and photoluminescence spectra measurements. The phosphors can be efficiently excited by near ultraviolet (n-UV) light resulting in blue emission. The optimal Ce 3+ dopant concentrations in both compounds were determined, and the concentration quenching mechanisms were also discussed. The photoluminescence excitation (PLE) and emission (PL) spectra, and decay curves at liquid helium temperature were measured to analyze the crystallographic occupancy sites of Ce 3+ in the Ba 2 Ln(BO 3 ) 2 Cl (Ln ¼ Gd, Y) hosts. The thermal stabilities of the phosphors Ba 2 Ln(BO 3 ) 2 Cl:Ce 3+ (Ln ¼ Gd, Y) were studied using the dependence of the luminescence intensities on temperature (300-500 K), and their luminescence quenching temperatures and thermal activation energies were also determined. The results indicate that the phosphor Ba 2 Gd(BO 3 ) 2 Cl:Ce 3+ offers excellent optical properties as a potential blue-emitting phosphor candidate for n-UV LEDs, such as a higher thermal stability and a stronger luminescence intensity, than those of the phosphor Ba 2 Y(BO 3 ) 2 Cl:Ce 3+ .

No abstract

No abstract

No abstract