Investigation on the site occupation of rare-earth ions in CaIn2O4 with the fluorescence probe of Eu3

Two Novel Fluorescent Probes as Systematic Sensors for Multiple Metal Ions: Focus on Detection of Hg2

Many precedents prove that fluorescent probes are promising candidates for detection of metal ions in the environment and biological systems. Herein, two novel photoinduced electron transfer (PET)-based fluorescent probes, CH 3 -R6G and CN-R6G, were rationally synthesized by incorporating a triazolyl benzaldehyde moiety into the rhodamine 6G fluorophore. The optical properties of these probes were studied using an ultraviolet-visible (UV-vis) absorption spectrophotometer and a fluorescence spectrophotometer. Through the analysis of the test results, it is concluded that the selectivity and sensitivity of these two probes to Hg2+ are better than to other metal ions (Ag+, Al3+, Ba2+, Cd2+, Co3+, Cu2+, Cr3+, Fe3+, Ga2+, K+, Mg2+, Na+, Ni2+, Pb2+, and Zn2+). According to the standard curve diagram, the detection limits of CH 3 -R6G and CN-R6G were determined to be 1.34 × 10-8 and 1.56 × 10-8 M, respectively. Reaction of the probes with Hg2+ resulted in a color change of the solution from colorless to pink. The corresponding molecular geometric configuration, orbital electron distribution, and orbital energy of these two compounds were predicted by density functional theory (DFT). The two probes CH 3 -R6G and CN-R6G have been successfully used for imaging Hg2+ in live breast cancer cells, thereby indicating their great potential for the micro-detection of Hg2+ in vivo.

One-step surfactant-free controllable synthesis and tunable up-conversion/down-shifting white light emissions of Sr2YF7 crystals doped with Ln3+ ions

In this work, uniform and monodisperse Sr₂YF₇ spheres were successfully synthesized via a facile one-step hydrothermal route without employing any surfactant.

Color-Tunable Binuclear (Eu, Tb) Nanocomposite Powder for the Enhanced Development of Latent Fingerprints Based on Electrostatic Interactions

Fluorescence color of rare earth-based nanopowder can be modulated by regulating the molar ratio of components, which offers a promising strategy in many fields of applications. Herein, a series of binuclear Eu _xTb_{1- x}(AA)₃Phen ( x = 1, 0.75, 0.5, 0.25, 0.1, 0) complexes were fabricated using acrylic acid (AA) as the first ligand and using 1,10-phenanthroline (Phen) as the second ligand. The characterization results showed that this novel binuclear (Eu, Tb) complex can emit strong red or green light via simply varying the molar ratio of europium and terbium. Moreover, the results of spectroscopic and zeta potential analyses suggested that there was an electrostatic adherence mode in the interaction between the Eu _xTb_{1- x}(AA)₃Phen complex and fingerprint residues. Importantly, our Eu _xTb_{1- x}(AA)₃Phen nanopowder was successfully applied to the enhanced development of latent fingerprints on various surfaces by the powder dusting method, exhibiting a high contrast, sensitivity, and selectivity, as well as a low detection limit in forensic science, which was further confirmed by analysis with an automatic fingerprint identification system. In summary, our synthetic rare earth-based nanopowder exhibits promise as an ideal fluorescent probe for the enhanced development of latent fingerprints, based not only on physical absorption at the macrolevel but also on electrostatic interactions between our rare earth complex and fingerprint residues at the molecular level, which could provide an enhanced affinity compared with traditional fingerprint powders.

Morphology/phase controllable synthesis of monodisperse ScVO4 microcrystals and tunable multicolor luminescence properties in Sc(La)VO4(PO4):Bi3+,Ln3+ phosphors

A facile one-pot hydrothermal approach was employed to prepare novel chocolate-like ScVO₄ microcrystals using polyethylene glycol as an additive.

808 nm-triggered optical thermometry based on up-conversion luminescence of Nd3+/Yb3+/Er3+ doped MIn2O4 (M = Ca, Sr and Ba) phosphors

808 nm driven UCL mechanism and intrinsic structure-dependent optical thermometric performance of MIn₂O₄:Nd³⁺/Yb³⁺/Er³⁺ (M = Ca, Sr, and Ba) are elucidated.