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Micron/sub-micron hard X-ray imaging is an important development direction of X-ray detection technology. Scintillation screens with excellent X-ray stopping power and high light output are desired to obtain good imaging quality. Europium-doped lutetium oxide (Lu 2 O 3 :Eu) film with micro-columnar structure is an ideal candidate for this application. In this study, micro-columnar structured Lu 2 O 3 :Eu films were prepared on quartz glass substrates by laser chemical vapor deposition (LCVD) method. The influences of preparation conditions on structure and morphology properties of films were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Photoluminescence and scintillation properties of the films, including photoluminescence excitation (PLE), photoluminescence (PL), PL decay, X-ray excitation luminescence (XEL), and afterglow curves, were recorded. The relationships between structure, morphology, luminescence properties of films, and preparation conditions were investigated and discussed as well. The preparation conditions include laser power, oxygen flow rate, and precursor evaporation temperature. In addition, dual-layer Lu 2 O 3 :Eu film was prepared for the first time by just turning off the laser. [ABSTRACT FROM AUTHOR]

Pr3+ doped high density germanate glasses were prepared by the melt-quenching method. The physical and luminescent properties were investigated. The glass containing BaF 2 represented maximum phonon energy of 810 cm−1, and the glass density was greater than 6 g/cm3. The glass exhibited good radiation resistance under 2 h of X-ray irradiation. Intense blue, green emissions and weak red emissions were observed when the glass was excited by X-ray, and the blue fluorescence lifetimes were in the range of 9.15–12.59 μs The results show that Pr3+ doped germanate glass could be a potential scintillating material in the field of X-ray detection for fast events. [ABSTRACT FROM AUTHOR]

Lead-free halides, with the advantages of non-toxicity and high stability, have broad application prospects. Here, we studied the synthesis and luminescent properties of the Sb-doped Rb 2 ZnCl 4 and explored their utilizations for white light-emitting diode (WLED) and X-ray detection. The as-synthesized Rb 2- x Zn 1- x Sb x Cl 4 single crystals exhibit bright red emission centered at 740 nm with a large full width at half maximum (FWHM) of 220 nm, and the maximum photoluminescence quantum yield (PLQY) is determined to be 59.7 % for the sample with x = 0.01. The assembled WLED achieves a high color rendering index (CRI) of 93.6 and a low correlated color temperature (CCT) of 3755 K. Under continuous X-ray irradiation for 600 s at a dose rate of 26.5 Gy min−1, the irradiation luminescence intensity of Rb 1.99 Zn 0.99 Sb 0.01 Cl 4 did not decrease, indicating that the single crystal has a high tolerance to X-ray irradiation. Our work demonstrates that Zn halides are also a promising lead-free family for multiple optoelectronic applications. • Significantly improve the luminescence properties of Rb 2 ZnCl 4 by doping with Sb. • The effect of Sb doping concentration on luminescence properties of Sb-doped Rb 2 ZnCl 4. • Sb-doped Rb 2 ZnCl 4 show high stability in WLED and X-ray detection applications. [ABSTRACT FROM AUTHOR]

Ce3+ activated high-density lanthanum lutetium germanate glass was fabricated by melt quenching method. Their densities, fluorescence decay curves, transmittance spectra, and luminescence excited by UV light and X-ray were measured and investigated. The densities of the glasses are between 5.90 g/cm3 and 5.97 g/cm3. The glasses present blue emission upon 379 nm light and X-ray. The blue emission lifetimes of the glasses are between 11.26 ns and 18.83 ns. The results shows that Ce3+ activated high-density lanthanum lutetium germanate glass would be a potential fast-event X-ray detection scintillating material. • Ce3+ doped germanate glasses with density around 6 g/cm3 were prepared. • The glass showed blue emissions upon UV light and X-ray. • The blue emission lifetimes were in the range of 11.26–18.83 ns. [ABSTRACT FROM AUTHOR]

The urgent demand for radiation detection in diverse applications boosts extensive investigations on scintillators. However, the current scintillating materials are mostly limited to mono-crystals with high cost, restricted volume and time-consuming fabrication techniques. Here, we report an efficient and transparent Tb3+-doped Sr 2 GdF 7 glass ceramic (GC) prepared via simple melt-quenching method, and its optical response to X-ray. By incorporating Tb3+ into crystallized Sr 2 GdF 7 inside a typical aluminosilicate glasses, highly enhanced green emission was observed under UV and X-ray excitation. After thermal treatment, the internal and external photo-luminescence quantum yields can be as high as 59.1 and 26.4%, respectively, with the high transparency (65%@550 nm) preserved. More interestingly, this composite material, combining the advantages of oxide glasses and fluoride crystals, presents strong X-ray excited luminescence (XEL). Its XEL intensity is 194% of that of commercial BGO scintillator. Evidenced by detailed optical and structural properties, it can be concluded that rare earth ions activated bulk oxyfluoride glass ceramics with unique merits, such as low-cost, high efficiency and intense radio-luminescence, could be alternative scintillating materials for high energy ray detection. [ABSTRACT FROM AUTHOR]

Europium doped borosilicate glasses were prepared in CO reducing atmosphere. The glasses were systematically investigated through XPS, photoluminescence (PL), fluorescence decay curves and X-ray excited luminescence (XEL). XPS results show that the glasses contain Eu2+ and Eu3+ at the same time. Under the excitation of 360 nm light, only a broad blue emission with peak around 440 nm due to the 5d→4f transition of Eu2+ is observed, while the emissions from Eu3+ do not appear in the PL spectra. The fluorescence decay curves were monitored at 440 nm, and the measured lifetimes are in the range of 0.17–0.42 μs. The PL results indicate that the PL emission from Eu2+ is significantly intense than the PL emissions from Eu3+. Upon X-ray excitation, two main emissions with peaks at 445 nm and 616 nm corresponding to Eu2+ and Eu3+ are obtained. The XEL results reveal that the XEL emissions from Eu3+ are comparably intense as the XEL emission from Eu2+. The results indicate that europium doped borosilicate glass could be a potential scintillating material in X-ray detection filed. [ABSTRACT FROM AUTHOR]

A series of UVA-emitting LaB 3 O 6 :Ce3+ phosphors and La 0.96 Ce 0.04 B 3 O 6 /PMMA films were prepared. The calcining temperature, activator concentration and PL test temperature were studied for the luminescence properties of the phosphor. And the effect of phosphor content on transmittance and X-ray radiation capacity of the composite films was also studied. The results show that LaB 3 O 6 :Ce3+ emits continuous double peaks at 358 nm and 380 nm when excited at 333 nm, the fluorescence lifetime is about 10 ns, and the luminescence intensity at 150 °C is 73.71% of that at room temperature, which can be used as phosphors for UV phototherapy applications. Under X-ray excitation, the integrated intensity of the La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film has a good linear relationship with the X-ray tube current and tube voltage, and the X-ray imaging of a car key taken by La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film has good signal-to-noise ratio, which can be used for X-ray detection and imaging. • A UVA phosphor with good thermal stability can be applied to UV phototherapy. • LaB 3 O 6 :Ce3+ phosphor has no significant afterglow and can be used as scintillator material. • La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film with good X-ray radiation capability can be used for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

The Eu 3+ -doped CaO-Gd 2 O 3 -SiO 2 -B 2 O 3 glasses were prepared to study photoluminescence, lasing potential and scintillation properties. Glasses absorb photons in ultraviolet, visible light and near infrared regions and are assigned to the energy transitions of Gd 3+ and Eu 3+ . Ultraviolet with 275 nm can generate the strong red emission with 614 nm via energy transfer form Gd 3+ to Eu 3+ . X-ray scintillation study exhibits strong emission pattern due to Gd-Eu energy transfer. The optimum concentrations of Eu 3+ ion in this glass is 0.30 mol% as it results maximum emission intensity. The fluorescence lifetime of the 5 D 0 level decreases from 1.763 to 1.726 ms when concentration increased from 0.05 to 0.40 mol%. From Judd-Ofelt analysis, this glass exhibit high potential for using as laser medium for red laser device with high lasing power and energy extraction ratio. Moreover, this glass performs the integral scintillation efficiency as 13% compared with BGO. [ABSTRACT FROM AUTHOR]

The Gd 2 O 3 –La 2 O 3 –ZnO–B 2 O 3 –Eu 2 O 3 glasses with different Gd 2 O 3 concentration (Gd:LaZnBEu) were studied in the physical, structural, optical and luminescence properties. The density and refractive index of glass increased with addition of Gd 2 O 3 content. The FTIR spectra demonstrated the BO 3 and BO 4 borate complexes as the main construction in glass those were more disturbed by Gd 2 O 3 increasing. The BO 4 /BO 3 and bridging/non-bridging oxygen ratio, observed from XPS, changed by following the Gd 2 O 3 concentration whose 10 mol% owned the highest values of both ratios. In the absorption spectra, glasses absorbed some photons in UV – NIR region. The excitation by O2−→Eu3+ charge transfer (240 nm), Gd3+→Eu3+ energy transfer (275 nm) and direct Eu3+ excitation (394 nm) caused the strongest Eu3+ photoluminescence at 613 nm (5D 0 →7F 2). The glass with 5 mol%-Gd 2 O 3 , that possessed the optimum Eu3+ local site, exhibited the highest absorbance and photo-/radio-luminescence intensity. The CIE 1931 and UV lamp excitation revealed the strong reddish-orange emission of glasses. The photoluminescence decay time of Eu3+ in glasses were between 1.6 and 2.1 ms and decreased with added Gd 2 O 3 amount. The Gd:LaZnBEu glasses have a potential for LED, laser, display, and X-ray detection devices with integration mode. • The strong luminescence of Eu3+ under different excitations on Eu3+, Gd3+ and charge transfer. • High absorbance and luminescence intensity by the optimum BO 4 /BO 3 and BOs/NBOs ratio in glass. • The strong reddish-orange emission for LED, laser, display and X-ray detection applications. [ABSTRACT FROM AUTHOR]

We developed a two-stage microfluidic reactor consisting of one hot and one cold region to systematically investigate a radiolytic method to synthesize colloidal silver and to improve the sensitivity of radiation dosimeters based on the Ag nanoparticles plasmon intensity. The microfluidic approach avoided growth during the heating stage, resulting in the total absence of a plasmon band for non-irradiated samples, greater control of the particle size distribution, and decreased minimal detectable dose. Doses as low as 0.2 Gy could be detected with sensitivities higher than the reported in the literature. This is a great achievement once most chemical dosimeters, besides 3D gels, are not sensitive to such low doses. Samples prepared in the microreactor and exposed to doses from 0 to 0.75 Gy presented an unexpected absorption band above 500 nm and a fluorescence emission around 380 nm, evidencing the presence of Ag nanoclusters (AgNCs). Both, absorption and emission bands from AgNCs, increase in the 0-0.75 Gy range, suggesting that nucleation predominates in the microreaction stage and in the radiolytic step for doses below 1 Gy. Decreased fluorescence intensity and undetected absorption above 500 nm indicate that growth prevails for doses ≥ 1 Gy. Thus, our work presents a novel way to measure doses based on silver nanoclusters, including both absorption and emission as dosimetric parameters. Besides unveiling nucleation and growth mechanisms associated to nano clusters and particles formation in this radiolytic microreaction, the results put the spotlight on new possibilities for enhanced radiation detection employing AgNCs. [Display omitted] • Two-stage microfluidic reactor leads to decreased minimal detectable dose. • Microreaction results in silver nanoclusters (AgNCs) or nanoparticles (AgNPs). • Ag nanoclusters are formed for irradiation with doses below 0.75 Gy. • Doses as low as 0.2 Gy can be detected with both AgNPs and AgNCs. • AgNPs and AgNCs constitute a new multimodality platform for x-ray detection. [ABSTRACT FROM AUTHOR]

Ce 3 + –doped, Tb 3 + –doped and (Ce 3 + , Tb 3 + )–codoped BaO–Gd 2 O 3 –Al 2 O 3 –B 2 O 3 –SiO 2 glasses were prepared by high temperature melting method and their luminescence properties have been investigated under UV excitation. Ce 3 + –doped borosilicate glass has a strong purplish–blue emission with the maximum about at 399 nm. Tb 3 + –doped borosilicate glass shows bright green emission at about 545 nm. (Ce 3 + , Tb 3 + )–codoped borosilicate glasses present a broad band emission ranging from 350 to 475 nm except emitting light at about 490, 545, 588 and 624 nm. There is an effective energy transfer from Ce 3 + ion to Tb 3 + ion and Ce 3 + ion strongly sensitizes the luminescence of Tb 3 + ion in (Ce 3 + , Tb 3 + )–codoped borosilicate glasses. A fast luminescence decay time of Tb 3 + ion is in an order of ms in (Ce 3 + , Tb 3 + )–codoped borosilicate glasses, which indicates it could be useful for X–ray detection for slow event. [ABSTRACT FROM AUTHOR]

The Gd 2 Y (1-x) Dy x Al 2 Ga 3 O 12 phosphors were prepared by the solid state reaction to study in the structure, photon absorption, photo- and radioluminescence properties. The XRD represented a crystalline cubic with Ia 3 ‾ d space group as the main structure of phosphor. The Y atomic sites were fine replaced by Dy in phosphor structure with Dy content (x) in a range of 0.25–1.00. The grain sizes of phosphor samples observed by SEM were in several micrometers. In the absorption spectra, phosphors absorbed the photons with various wavelengths in UV, VIS and NIR region. Both direct Dy3+ excitation and Gd3+→Dy3+ energy transfer caused the strong photoluminescence (PL) of Dy3+ around 481 (4F 9/2 → 6H 15/2) and 582 (4F 9/2 → 6H 13/2) nm. The PL decay times of phosphors were around 0.10–0.74 ms. Phosphors performed the strong response to X-rays in radioluminescence (RL) spectroscopy which composed of the sharp emission of Dy3+ ion, broad emission of Y-related complex and weak emission of defects. Phosphor with 0.25 Dy content owned the highest PL and RL intensity of Dy3+ due to the concentration quenching effect and appropriate lattice constant, while free-Dy phosphor had the highest RL intensity of Y complexes. The Gd 2 Y 0.75 Dy 0.25 Al 2 Ga 3 O 12 phosphors is a promising material for the X-ray detection applications, especially the X-ray imaging screen. • X-ray detection ability from luminescence of Dy3+ ion and Y-complex. • Photoluminescence of Dy3+ surrounded by high-symmetry environment in phosphor. • Luminescence under the Gd3+ → Dy3+ energy transfer. • The influence of lattice constant on luminescence properties. [ABSTRACT FROM AUTHOR]

Developing efficient strategies to fabricate planar photoluminescence scintillators is of great importance to explore X-ray detectors with new platform. Rare-earth (RE) doped Lu 2 O 3 thin films are successfully fabricated by mild aqueous phase electrochemical deposition on ITO/glass substrates with low-temperature post-annealing treatment. The as-prepared Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) thin films exhibit steerable thickness, high transparency in the visible-NIR range, and low transmittance at UV band mainly due to the oxygen-metal (O2--RE3+) charge transfer processes and the 4f-4f transitions of the RE3+. The Lu 2 O 3 :RE3+ thin films emit intense red, green and blue (RGB) photoluminescence, which mainly correspond to the 5D 0 -7F 2 transition of Eu3+, 5D 4 -7F 5 transition of Tb3+ and 1G 4 -3H 6 transition of Tm3+ respectively. Moreover, the transparent Lu 2 O 3 :RE3+ thin films also exhibit high sensitivity and linearity luminescence to the X-ray stimulation in a dose rate from 30 to 160 mGy s−1. This rapid and energy-saving synthesis show high efficiency to fabricate rare-earth doped thin-film with a tunable optical performance for optoelectrical application in the fields of solar light concentrators, agricultural light conversion thin films, biosensors, photodetectors and especially the X-ray detectors. [Display omitted] • The thickness of Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) films prepared by electrodeposition is controllable. • The thin films exhibit high transparency at Visible-NIR band. • The Lu 2 O 3 :RE3+ thin films emit intense RGB photoluminescence upon UV light excitation. • The Lu 2 O 3 :RE3+ thin films exhibit high sensitivity and linearity to the X-ray. [ABSTRACT FROM AUTHOR]

The K 2 O–Gd 2 O 3 –B 2 O 3 –P 2 O 5 glass doped with Dy 2 O 3 (Dy:KGPB) were synthesized by the melt-quenching technique. These glasses were subjected to characterize the physical, structure, optical and luminescence properties. It was observed that the density, molar volume and refractive index of glass increased with increasing Dy 2 O 3 concentration. The FTIR result confirmed the main glass network of B O B and P O P linkages those were degraded by adding Dy 2 O 3 modifier. Glasses absorbed photons in ultraviolet, visible light and near-infrared region. The photoluminescence under direct Dy3+ excitation performed the strong emissions at 574 and 482 nm corresponding to 4F 9/2 → 6H 13/2 and 4F 9/2 → 6H 15/2 transition, respectively. The Gd3+ excitation also caused strong emission of Dy3+ by the Gd3+-Dy3+energy transfer. Glass doped with 1.00 mol% of Dy 2 O 3 owned the highest emission intensity due to the concentration quenching. The lifetime of 4F 9/2 level was found to decrease with addition of Dy 2 O 3 content via dipole-diploe interaction between Dy3+ ion. Judd-Ofelt (J-O) intensity parameters were initially calculated and applied to evaluate the radiative parameters such as branching ratios, radiative transition probabilities, and stimulated emission cross-sections. The radioluminescence of glass was also investigated and found the scintillation efficiency around 15.6%, compared to BGO scintillator. The Dy:KGPB glass has an interesting potential for solid-state laser, LED and X-ray detection applications. • The energy transfer phenomenon was observed from Gd3+-Dy3+ ions. • The bright greenish-yellow emission was observed for present glasses. • Energy transfer parameter show increasing trend with increase in Dy3+ ions. • X-rays scintillation efficiency of glass was 15.6% compared to BGO scintillator. • CIE chromaticity diagram show greenish-yellow emission under UV lamp excitation. [ABSTRACT FROM AUTHOR]

• PL, XEL and sensing properties of Er3+ and Er3+/Yb3+ doped Gd 2 Zr 2 O 7 are studied. • A good radiation resistance is realized for these samples with pyrochlore structure. • Er3+ emissions keep stable under continuous X-ray excitation. • FIR of 2H 11/2 to 4S 3/2 is insensitive to excitation powers with S r-max of 1.1% K−1. • Er3+/Yb3+: Gd 2 Zr 2 O 7 can be used for optical thermometry and X-ray detection. A series of Er3+-doped and Er3+-Yb3+ co-doped Gd 2 Zr 2 O 7 phosphors were synthesized via hydrothermal method, and their multifunctional properties were studied in detail. The Raman spectra indicated that the products were the ordered pyrochlore phase of Gd 2 Zr 2 O 7 , which exhibited a good radiation resistance. The up-conversion (UC), down-conversion (DC) photoluminescence (PL) and X-ray excited luminescence (XEL) spectra of the Er3+: Gd 2 Zr 2 O 7 samples showed the similar spectra profiles, which were composed of the prominent green (2H 11/2 /4S 3/2 →4I 15/2) and weak red (4F 9/2 →4I 15/2) emissions. The co-doping of Yb3+ ions was beneficial for the improvement in UC PL but led to the reductions in DC PL and XEL. Besides, the X-ray induced green emissions demonstrated a high-sensitivity to the dose rate and a long-term stability against the continuous X-ray irradiation. Moreover, using the fluorescence intensity ratio (FIR) technique, the temperature sensing behaviors were analyzed based on the thermally coupled levels (TCLs) 2H 11/2 and 4S 3/2 of Er3+. The FIRs were found to be insensitive to the excitation power variation, and the optimal relative sensing sensitivity reached ~1.1%K−1 at 298 K. These characteristics may enable the studied system applicable for optical thermometry, X-ray detection and X-ray imaging. [ABSTRACT FROM AUTHOR]

A novel Eu3+ ions-based metal–organic coordination polymer with a peculiar "snake-shaped" chain structure has been synthesized, which exhibits efficient light emission, excellent line response to X-rays and high structure and luminescence stability against continuous irradiation. [Display omitted] • A new type of luminescent Eu-MOCP was synthesized by simple solvothermal method. • Synthesized Eu-based MOCP shows an efficient and stable light emission under X-ray excitation, and delivers an excellent linear response to X-ray dose. • Compound 1 demonstrates high structure and luminescence stability against continuous X-ray irradiation. In this paper, a novel Eu ions-based metal–organic coordination polymer (MOCP) named Eu(1,3,6,8-PTS)(H 2 O) 7 ·4H 2 OHbipy (1) (PTS = pyrenetetrasulfonic acid) has been prepared, and its structure, stability, photoluminescence and scintillation properties were systematically investigated. Compound 1 gives a peculiar "snake-shaped" chain structure with the aid of π-π stacking effect of 4,4′-bipyridine auxiliary template. An efficient and stable light emission was detected under X-ray irradiation, which presents an excellent linear response to X-ray dose. Moreover, this compound demonstrates high radiation stability, illustrating its potential as a scintillator for X-ray detection. This work not only provides guidance for the design and fabrication of sulfonic ligand derived MOCPs with Eu (III) ions coordiantion, but also demonstrates the potential of MOCPs scintillators for X-ray detection technology. [ABSTRACT FROM AUTHOR]

The physical, structural, optical, shielding, thermal and luminescence properties of WO 3 -Gd 2 O 3 –B 2 O 3 glasses were studied in this work. The effect of WO 3 replacement by Gd 2 O 3 on radiation shielding and radiation detection potential was evaluated. The glass density increases with increasing Gd 2 O 3 concentration and the maximum value is 5.97 g/cm3. The FTIR and XRD result confirm that the trigonal BO 3 , tetrahedral BO 4 and tungsten complex are the main chemical groups and coorperate into the amorphous structure of glass. The optical absorption spectra exhibit the absorbance of glasses in ultraviolet and visible light region. The shielding parameters of glasses, such as mass attenuation coefficient, effective atomic number, electron density and half value layer, were investigated theoretically and experimentally. They perform a small degradation of shielding property by increasing Gd 2 O 3 content. There is no obvious dependence of Gd 2 O 3 concentration on glass thermal conductivity and expansion. The strong photoluminescence of [WO 6 ]6- group with 524 nm occurred under its charge transfer excitation and under the energy transfer from excited Gd3+ ion. In the radioluminescence, WGB glasses emitted the visible light with 562 nm based on the mixed emission from [WO 6 ]6- group and oxygen vacancy. The glass possesses the X-ray detection efficiency around 18.65% of BGO crystal. The WO 3 –Gd 2 O 3 –B 2 O 3 glass with 17.5 and 27.5 mol% of Gd 2 O 3 is a promising γ-ray shielding material at room temperature and high temperature circumstance, respectively and one with 25 mol% of Gd 2 O 3 owns the attractive potential for the X-ray radiation detection applications. • The self-luminescence of WO 3 –Gd 2 O 3 –B 2 O 3 glass. • X-ray detection ability. • High radiation shielding quality compared to shielding concrete and Schott's glass. • High-density glass. [ABSTRACT FROM AUTHOR]

A promising composite scintillator for used in ultrafast X-ray detection was successfully developed by compounding Cl-doped CuI phosphor with polystyrene (PS) (CuI:Cl-PS), and its crystal structure and luminescence characteristics were investigated in detail. The CuI:Cl-PS composite scintillator only exhibited an intense near-band-edge (NBE) luminescence with a decay time of sub-nanosecond, and the slow luminescence of CuI was entirely suppressed under the excitation of ultraviolet light or X-ray. Furthermore, the intensity of the ultrafast NEB emission for the composite scintillator was not basically deteriorated after storage in air at room temperature for six months. It is expected that the CuI:Cl-PS composite scintillator demonstrates a great potential application in ultrafast hard X-ray detection or imaging. • The CuI:Cl-polystyrene (CuI:Cl-PS) composite scintillator was successfully synthesized, and firstly proposed to use in ultrafast X-ray detection. • The CuI:Cl-PS scintillator has only an intense near-band-edge (NBE) emission under X-ray excitation. • The decay time of NBE emission for CuI:Cl-PS scintillator is up to sub-nanosecond, which is greatly significant for ultrafast X-ray detection. • The intensity of NBE for CuI:Cl-PS scintillator is not basically deteriorated after storage for 6 months in air. [ABSTRACT FROM AUTHOR]

• Laser chemical vapor deposition can significantly increase deposition rates. • The use of sapphire substrate helps to reduce thermal stress. • Micro-columnar film achieves high spatial resolution without reducing thickness. • The film in synchrotron radiation X-ray detection shows sub-micrometer resolution. Lu 2 O 3 :Eu scintillation film is one of the most attractive candidate for the hard X-ray imaging, especially for sub-micrometer spatial resolution X-ray detectors. This study was focused on the preparation and characterization of Lu 2 O 3 :Eu structured scintillation film on (0 0 1) sapphire substrate by laser chemical vapor deposition (LCVD). The grazing incidence X-ray diffraction (GIXRD) measurement shows that the film with thicknesses of 3 μm is oriented along the (4 1 1) direction. The morphology and luminescent properties, including photoluminescence excitation (PLE), photoluminescence (PL) and PL decay, were measured and discussed. The sub-micrometer spatial resolution was obtained at BL13W1 station at Shanghai synchrotron radiation facility (SSRF). [ABSTRACT FROM AUTHOR]

Tb3+ ions single-doped transparent oxyfluoride glass-ceramics (GC) containing LiYF 4 nanocrystals were prepared via a conventional high-temperature melt quenching way and subsequent further thermal-treatment. The microstructure and related luminescent properties of the composite materials were studied in detail. It was confirmed by XRD and TEM techniques that the precipitated particles in the glass phase of the GC590-4h sample were LiYF 4 nanocrystals having a size of approximately 26 nm. Compared to the PG sample, the luminescence intensity of the GCs at 378 nm light excitation was significantly enhanced and the corresponding lifetime was prolonged. This is because the Tb3+ ions are preferentially enriched in the precipitated low-phonon-energy LiYF 4 nanocrystals, which can effectively induce the reduction of non-radiative transitions. It is worth noting that the emission intensity of Tb3+ single-doped GCs containing LiYF 4 nanocrystals at 545 nm (5D 4 →7F 5) is also greatly improved (under X-ray excitation). The obtained results indicate that Tb3+ single-doped LiYF 4 GC may have the potential to be a novel scintillator applied to X-ray detection for the slow event. • Tb3+-doped transparent oxyfluoride glass ceramics containing LiYF 4 nanocrystals. • Have the potential of a novel scintillator. • The enhancement of the luminescence were improved under ultraviolet and X-ray excitation. [ABSTRACT FROM AUTHOR]