Energy transfer and the anti-thermal quenching behavior of Sr8MgCe(PO4)7:Tb3+ for temperature sensing

Defect compensation and intervalence charge transfer state-based Pr3+-doped niobate antithermal quenching phosphors

Herein, a scheme of Sr2+/Ca2+ ion substitution was employed to simultaneously regulate the defect and intervalence charge transfer (IVCT) state of Sr2-xCaxNb2O7:Pr3+ phosphors, resulting in a dual-modulation strategy for enhancing phosphor thermal stability.

Realizing near white and warm light emission of cuprous iodide complexes by alkyl-isomerization of ligands

Four novel all-in-one structured cuprous iodide hybrid materials are presented. Isomerization of the alkyl chain on the ligand improved material thermal stability and regulated their luminescence to warm and near-white light emission, with the internal quantum yield increasing from 5% to 83%. This provides a reasonable route for designing white light emitting cuprous iodide materials for solid-state lighting in future.

Optical temperature-sensing properties based on upconversion luminescence of La9.31Si6.24O26:Er3+,Yb3+ with different strategies

A series of novel La_9.31Si_6.24O₂₆:Er³⁺,Yb³⁺ (LS:Er³⁺,Yb³⁺) luminescent materials have been successfully synthesized by conventional solid-state reaction method. The phases, morphologies and upconversion (UC) luminescence properties were systematically researched by XRD, SEM, PL spectra, etc. The optimum Yb³⁺ concentration in LS:1%Er³⁺,xYb³⁺ was determined to be ×  = 15%, above which the concentration quenching effect appeared due to the increasing energy back transfer from Er³⁺ to Yb³⁺. Meanwhile, the FIR technique (by using I₅₂₂/I₅₅₄ and I₆₆₀/I₅₂₂ of Er³⁺) was employed to study the temperature-sensing performance. As the rise of temperature for all the different Yb³⁺ concentrations, the values of the absolute sensitivity S_A increased first and then decreased by utilizing I₅₂₂/I₅₅₄, but showed continuous decrease by using I₆₆₀/I₅₂₂. For the relative sensitivity S_R, it has been found that the S_R values for all the samples exhibited gradual decrease with rising temperature. Besides, the experiment of the heating-cooling cycles between 283 and 523 K proved that the LS:Er³⁺,Yb³⁺ material has good reversibility and repeatability. The above results indicated that the LS:Er³⁺,Yb³⁺ may be a potential candidate for optical temperature sensor.