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A series of Sm3 +-doped 0. 96Na0 .5Bi0.5TiO3-0.04CaTiO3 (NBT-0. 04CT:xSm3+, 0. 002 ≤x ≤ 0. 020) lead-free piezoelectric ceramics were prepared by a conventional solid-state reaction method. The phase structures of the samples were characterized by X-ray diffractometry, and all the samples show a single perovskite structure. The photoluminescence properties of the samples were measured by fluorescence spectrophotometer, and the samples show the strongest excitation peak at 479 nm, which matches well with the blue LED chip used in the white LED synthesis. The dominant emission peak is located at 597 nm (4G5/2→ 6 H7/9), presenting strong orange-red luminescence. NBT-0. 04CT:0. 010Sm3+ ceramics shows optimal luminescence performances among the Sm3 +-doped NBT-0. 04CT ceramics, and superior thermal stability of its luminous properties is achieved in the temperature range from 278 K to 473 K. The results indicate that NBT-0. 04CTxSm3 + ceramics have promising applications in white LED. [ABSTRACT FROM AUTHOR]

Samples of (110), (100), and (111) MgO single crystals were implanted with 70 keV N ions at room temperature. All as-implanted samples showed room temperature hysteresis in magnetization loops. The observed saturation magnetization (Ms) was 0.79 × 10−4 emu/g, 1.28 × 10−4 emu/g, and 1.5 × 10−4 emu/g for (110), (100) and (111) orientation implanted-MgO and follows the relation Ms(111) > Ms(100) > Ms(110), indicative of crystalline orientation-dependent ferromagnetism in N-implanted MgO. The samples were characterized by X-ray photoelectron spectroscopy (XPS), high resolution X-ray diffraction (HRXRD), reciprocal space mapping (RSM), and photoluminescence (PL). The results indicated that the amount of N-substitute-O and N-interstitial defects in these three N-implanted MgO samples showed the same changing tendency as compared with Ms data. Thus, we conclude that the N-substitute-O and N-interstitial defects may play a crucial role in controlling the N+-implanted-induced ferromagnetism. [ABSTRACT FROM AUTHOR]

A series of Ho3+-doped 0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3 lead-free piezoelectric ceramics (NBT-0.06BT: x Ho3+, 0.0025≤ x ≤ 0.03) are prepared by a conventional solid-state reaction method. Under the excitation of 980 nm, all the samples exhibit strong green, red and near infrared upconversion emissions, which are ascribed to the 5F 4 /5S 2 →5I 8 (∼547 nm), 5F 5 →5I 8 (∼656 nm), 5F 4 /5S 2 →5I 7 (∼756 nm) transitions of Ho3+ ions, respectively. The NBT-0.06BT: 0.015Ho3+ ceramic displays the optimal emission among these Ho3+-doped NBT-0.06BT solid solutions. Optical thermometry behavior is evaluated via fluorescent intensity ratio (FIR) of green to red emissions of Ho3+ ions. The temperature sensing performances is investigated in the temperature range of 293–473 K based on non-thermally coupled levels (NTCL). The maximum relative sensitivity is found to be 0.35% K−1 at 293 K. The present investigation results imply the promising application of NBT-0.06BT: Ho3+ in non-contact optical thermometers. • Under a 980 nm diode excitation, the NBT-0.06BT: x Ho3+ specimens exhibit strong prominent green emission. • The upconversion photoluminescence intensity exhibits extremely sensitive to temperature in range of 293–473 K. • A maximum relative sensitivity of 0.35% K−1 at 293 K is obtained for NBT-0.06BT: 0.015Ho3+ ceramic. [ABSTRACT FROM AUTHOR]

• The quantum cutting was directly observed and confirmed in CGP:Tm3+. • The improved QC model was established in Tm3+ ion. • The effect of Tm3+ concentration on the spectral characteristics was clarified. • The investigations can help to understand the QC and ET processes in Tm3+. In this work, to develop new quantum cutting (QC) luminescent materials and clarify the QC process, a series of Tm3+-activated Ca 9 Gd(PO 4) 7 (CGP) phosphors were prepared by conventional high-temperature solid state reaction method. The phase purity of the samples was checked by XRD patterns, and the structural features were analyzed on the basis of Rietveld refinement. The emission spectra of Tm3+ were measured by exciting at different wavelengths, in which the QC was identified. The main QC model was proposed when the Tm3+ is excited into 1D 2 level. The occurrence of QC was further verified by comparing the decay lifetimes on 3H 4 level under 357, 470 and 685 nm excitation. With increasing Tm3+ concentration, it was found that the 3H 4 →3H 6 transition intensity around 806 nm exhibits faster increase rate than other ones by exciting at either 357 or 470 nm. This increase rate is more effective under 357 nm excitation thanks to the existence of QC process. The above investigation could show instructional significance for the development of other rare earth ions doped luminescent materials. [ABSTRACT FROM AUTHOR]

Luminescent temperature sensors based on photoluminescent materials have received considerable attention for their advantages of quick and noninvasive measurement. In this paper, a series of Tb3+, Eu3+ single-doped and co-doped Ca 2 Al 2 SiO 7 (CAS) phosphors were synthesized by sol-gel method. The phase purity, surface morphology, energy transfer, luminescence characteristics and temperature sensing properties of Tb3+, Eu3+ doped CAS phosphors have been studied carefully. Due to the energy transfer of Tb3+→Eu3+, CAS: Tb3+, Eu3+ phosphors demonstrate tunable luminescence under 238 nm excitation, in which the luminescence color gradually changes from purple-red to cool white, and then to warm white by continuously increasing the concentration of Tb3+ ions. The elongation of the fluorescence lifetime of Eu3+ with increasing Tb3+ ions content further confirms the energy transfer of Tb3+→Eu3+. The thermal behavior of CAS: Tb3+, Eu3+ phosphors shows enhanced luminescence intensity for 404 nm emission while suppressed luminescence intensity for 616 nm emissions with raising temperature, implying its potential in optical temperature sensing. Therefore, the temperature sensing performance is evaluated by using the fluorescence intensity ratio (I 404 nm /I 616 nm) in CAS: Tb3+, Eu3+ phosphors, showing a maximum relative sensitivity of 1.17%K−1 at 443 K. These results indicate that CAS: Tb3+, Eu3+ phosphors are promising candidates for tunable luminescence and non-contact temperature sensing. [ABSTRACT FROM AUTHOR]

A series of Sm3+ doped 0.92(Na 0.5 Bi 0.5)TiO 3 -0.08(Ba 0.90 Ca 0.10)(Ti 0.92 Sn 0.08)O 3 (NBT-8BCTS: x Sm3+, x = 0–0.025) lead-free piezoelectric ceramics are fabricated via a conventional solid-state reaction method, and their phase structure, photoluminescence properties and temperature dependent of luminescence spectra are studied in detail. The emission spectra with dominant orange-red emission consist of four emission peaks at 542 nm, 598 nm, 644 nm and 709 nm, which are ascribed to the 4G 5/2 → 6H J/2 (J = 5, 7, 9, 11) transition of Sm3+ ions, respectively. Furthermore, the optical temperature sensing properties of the NBT-8BCTS: 0.01Sm3+ ceramic in the temperature range between 313 K and 533 K are analyzed with a maximum relative sensitivity 1.29%K−1 at T = 463 K. Besides, the phosphors exhibit excellent stable temperature sensing performance under repeated heat-cooling cycles. These results suggest that the Sm3+ doped NBT-8BCTS ceramics may have potential applications in multifunctional sensing devices by integrating its optical temperature sensing and intrinsic ferroelectric property. [Display omitted] • Ferroelectricity and photoluminescence emissions coexist in NBT-BCTS: x Sm3+. • A maximum relative sensitivity of 1.29% K−1 at 463 K is obtained. • Sm doped NBT-BCTS ceramics have potential for developing multifunctional optical-electric devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Organotin(IV) complexes 2 and 4 exhibited strong cytostatic activity towards HeLa and HepG-2 cell lines. Meanwhile, the complex 4 exhibited much stronger inhibition against five common plant pathogenic fungi in vitro. Then, the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs were used to study changes on the fungal morphology for the treatments with the complex 4, which indicated the complex 4 can damage the cell wall of mycelia. • The organotin(IV) complexes 1 – 4 formed varieties of supramolecular structures. • The organotin(IV) complexes 2 and 4 showed higher anticancer activities. • Complex 4 exhibited a broad spectrum of antifungal potential activity. • Complex 4 could break down the cell wall of the fungus. Four new organotin(IV) complexes, [(Me 2 Sn) 4 O 2 (C 10 H 10 F 2 NO 4 S) 4 ] (1), [(n -Bu 2 Sn) 4 O 2 (C 10 H 10 F 2 NO 4 S) 4 ] (2), [Me 3 SnC 10 H 10 F 2 NO 4 S] (3) and [ n -Bu 3 SnC 10 H 10 F 2 NO 4 S] (4) have been synthesized by the reactions of 2,6-difluoro-3-(propylsulfonamido)benzoic acid with R 2 SnO (R = Me, and n -Bu) or R 3 SnCl (R = Me, and n -Bu). The four complexes have been characterized by elemental analysis, FT-IR, NMR (1H, 13C and 119Sn), and X-ray crystallography. The X-ray crystallography analyses revealed that the complexes 1 and 2 represent tetranuclear tin ladder-like geometries. In comparison, complexes 3 and 4 exhibit 1D zig-zag chains. Complex 1 constructs a 2D planar structure by N H···O and C H···O intermolecular hydrogen bonding. Complex 2 constructs a 3D supramolecular framework via the C H···O and C H···F intermolecular hydrogen bonding. The 3D supramolecular frameworks of complexes 3 and 4 were formed by S O···H intermolecular hydrogen bonding, respectively. Furthermore, in vitro cytostatic activity of complexes 1 – 4 against the cervical carcinoma (HeLa) and the hepatocellular carcinoma (HepG-2) cell lines were examined by MTT screening. Results indicated that complexes 2 and 4 exhibited strong cytostatic activity. Meanwhile, the inhibition of complexes 1 – 4 against five common plant pathogenic fungi in vitro was obtained by the mycelial growth inhibition method, and the results revealed that complex 4 exhibited much stronger inhibition. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs were used to study changes on the fungal morphology for the treatments with complex 4. [ABSTRACT FROM AUTHOR]

Eu3+ singly-doped Ba 2 La 6 Y 2 (SiO 4) 6 O 2 phosphors with hexagonal structure have been synthesized by the high-temperature solid-state reaction method. The crystal structure of the samples was analyzed. To investigate the site occupation of Eu3+ in Ba 2 La 6 Y 2 (SiO 4) 6 O 2 , the photoluminescence behavior of the phosphor was studied systematically. The emission spectra under specific wavelength excitations and the excitation spectra by monitoring emissions at 5D 0 →7F 0 transition wavelengths indicated that Eu3+ ions have entered two distinct sites in the compound. According to the concentration-dependent photoluminescence properties, the preferential site occupation was illustrated. In addition, the temperature-dependent PL measurement results revealed the high thermal stability of the sample and its application potential as a noninvasive optical thermometer. This work may help to provide an alternative approach to study the site occupation of Eu3+ ions in other functional materials. • A new Eu3+-activated Ba 2 La 6 Y 2 (SiO 4) 6 O 2 phosphor was synthesized via solid-state method. • The site occupation of Eu3+ was investigated according to the photoluminescence properties. • The phosphor has a high thermal stability. • The synthesized sample could have application potential as a noninvasive optical thermometer. [ABSTRACT FROM AUTHOR]