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Mechanical luminescence (ML) is the conversion of mechanical energy into light energy when a material is subjected to a force. It is challenging to develop ML materials with tunable luminescent properties by single ion doping, which have broad application prospects in the fields of stress sensing and dynamic signature anticounterfeiting. In this study, a Pr3+ doped Sr2Ga2GeO7 tunable ML material is reported. Due to the traps resulting from unequal substitution of Pr3+–Sr2+ in [SrO6] heptahedra, the deep/shallow traps redistribution occurs towards a multicolor ML from red to green. In addition, even after continuous friction sliding force (15 N), the ML intensities can be recovered after ultraviolet pre‐irradiation, indicating that Sr2Ga2GeO7: Pr3+ has excellent ML emission stability. Based on thermoluminescence analysis, potential PersL and ML mechanisms are further elaborated by a lattice engineering (trap regulation) strategy. In all, the development of single‐ion doped multicolor ML materials may have crucial research value and show a variety of potential applications in the fields of anticounterfeiting and information encryption. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) materials have found potential applications in information storage, anti‐counterfeiting, and stress sensing. Conventional stress sensing based on absolute ML intensity is prone to significant mistakes owing to the unpredictability of measurement surroundings. However, implementing a ratiometric ML sensing technique may considerably ameliorate this issue. In this study, a single activator‐doped gallate material (LiGa5O8:Pr3+) is proposed to determine the relationship between the ML intensity and the change in local positional symmetry that occurs when the material is subjected to stress. The sensing reliability of the ML intensity ratio under different factors (Force; Content; Thickness and Materials) is systematically analyzed, where the factor that has the greatest effect on the proportional ML is the concentration, with the ML intensity asymmetry ratio decreasing from 1.868 to 1.300 varying concentration at constant stress. The colour‐resolved visualization of stress sensing is further realized, which opens a new path for a ratiometric ML‐based strategy to improve the reliability of stress sensing. [ABSTRACT FROM AUTHOR]

Luminous properties play an essential role in phosphor-converted white light-emitting diodes for high-quality illumination, where the self-reducing behavior of doped activators and their excellent thermal stability have received significant attention. Here, we prepared NaY9Si6O26:Mn2+ red phosphors by a high-temperature solid-state reaction method, which achieved self-reduction of Mn4+ → Mn2+ and excellent thermal stability (luminous intensity at 420 K is 98% of that at room temperature) under ambient conditions. First-principles calculations and X-ray photoelectron spectroscopy elucidated a self-reduction mechanism from Mn4+ to Mn2+. The defect types were calculated in conjunction with thermoluminescence, verifying that the low thermal quenching properties originated from the transfer of electrons from the defect energy level to the Mn2+ excited state center induced by the cationic vacancy defect, which suppressed the luminescence loss from thermal quenching. In this work, the effect of defects on luminescence properties is highlighted and the further exploration of defect control is stimulated, opening up a new avenue for new types of highly thermally stable materials. [ABSTRACT FROM AUTHOR]

A novel, magnetic, p – n heterojunction-structured La 0.7 Sr 0.3 MnO 3 /g-C 3 N 4 (LS/CN) photocatalyst was designed by hybridizing p -type La 0.7 Sr 0.3 MnO 3 with n -type g-C 3 N 4. Several characterizations showed that the as-preparedLS/CN-0.5 nanoparticles possessed a saturation magnetization of 27.3 emu/g, coercivity of 60.3 Oe, specific surface area of 25.68 m2/g, and average particle size of 23 nm. The photocatalytic investigation determined a degradation efficiency of 95.0% for a 100-mL tetracycline solution with an initial concentration of 50 mg/L within 210 min over 0.05 g of the LS/CN-0.5. Experiments showed that LS/CN-0.5 exhibited good reusability, where a degradation efficiency of 88.6% was obtained after six cycles. It was found that the p – n heterojunction realized the excitation of photogenerated electrons in the high-potential conduction band of La 0.7 Sr 0.3 MnO 3. Furthermore, the synergistic effects of oxygen vacancies and high-potential photogenerated electrons induced the generation of more superoxide radicals, leading to the high photocatalytic activity of LS/CN. This study demonstrates a new strategy to design and construct highly efficient, magnetic, p – n heterojunction photocatalysts. • Successfully prepared magnetic CN/LS p – n heterojunction photocatalyst. • The construction of p – n heterojunction creates more oxygen vacancies and introduces high-potential photogenerated electrons. • The synergistic effects of oxygen vacancies and high-potential photogenerated electrons induced the generation of more superoxide radicals. [ABSTRACT FROM AUTHOR]