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In this work, a novel environmentally friendly strategy toward phosphor-converted WLED employing Ce:YAG-doped glass via single-step low-temperature co-sintering technology was successfully synthesized, using low-cost PbO–B 2 O 3 –SiO 2 –ZnO glass as host, which showed good sintering behavior and high visible transparency under the sintering condition of 750 °C without noticeable interaction with phosphors. By simply changing thermal condition, phosphor doped concentration and specimen thickness for the viscous sintering of phosphor in glass (PiG), optical characterization of WLED can be easily tuned. As a result, it can be found that the ideal thermal condition is sintered at 700 °C for 40 min, the optimal amount of phosphor powder is controlled to be 5 wt% of the final mixture, and the best suitable thickness of specimens is 0.8 mm. The constructed PiG based WLED exhibits a high luminous efficiency of 134.33 lm/W, and a correlated color temperature of 4696 K as well as a color rendering index of 68.5. Enhanced thermal quenching property of PiG compared to phosphor with conventional silicone resin reveals the prominent feasibility of the present glass ceramic material in WLED application. [ABSTRACT FROM AUTHOR]

A general and facile chemical synthesis approach has been established for the successful doping of monodisperse semiconducting In 2 O 3 nanocrystals inside a porous transparent silica glassy matrix. The preparation of silica glassy matrix loaded with specific In 2 O 3 precursors is performed by using the sol–gel method. Then, the samples are sintered by using atmosphere control methods to generate the In 2 O 3 nanocrystals growth inside the deep volume of the silica matrix. The resulting In 2 O 3 nanocrystals are characterized by X-ray powder diffraction, energy dispersive X-ray spectrum and transmission electron microscopy. Photocatalytic activity of the as-prepared products is also measured, and the result shows that the photodegradation efficiency of silica glassy matrix has been significantly improved by doping In 2 O 3 nanocrystals. [ABSTRACT FROM AUTHOR]

Abstract: CuIn1−x Ga x S2 (x =0.5) flowers consisting of nanoflakes were successfully prepared by a biomolecule-assisted solvothermal route at 220°C for 10h, employing copper chloride, gallium chloride, indium chloride and l-cysteine as precursors. The biomolecule l-cysteine acting as sulfur source was found to play a very important role in the formation of the final product. The diameter of the CuIn0.5Ga0.5S2 flowers was 1–2μm, and the thickness of the flakes was about 15nm. The obtained products were characterized by X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction spectroscopy (SAED), and UV–vis absorption spectroscopy. The influences of the reaction temperature, reaction time, sulfur source and the molar ratio of Cu-to-l-cysteine (reactants) on the formation of the target compound were investigated. The formation mechanism of the CuIn0.5Ga0.5S2 flowers consisting of flakes was discussed. [Copyright &y& Elsevier]

We report the preparation of transparent Ce and Tb co-doped Y 3 Al 5 O 12 single crystal by the Czochralski method. The characterization of the resulting single crystal was accomplished by using X-ray powder diffractometer, scanning electron microscopy and energy dispersive X-ray spectroscopy. Absorption peak of the single crystal at about 460 nm has been obtained from ultraviolet–visible absorption spectrometer and their intensity is changed with different annealing condition. Its optical properties also have been investigated using fluorescence spectrometer. What’s more, its photoelectric parameters were studied by LED fast spectrometer. The constructed single crystal based white-light-emitting diode exhibits a high luminous efficiency of 140.89 lm/W, and a correlated color temperature of 4176 K as well as a color rendering index of 56.7, which reveal the prominent feasibility of the present single crystal material in white-light-emitting diode application. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots materials have achieved significant progress in the field of optoelectronics owing to their unique advantages, such as a wide color gamut, adjustable wavelength, and low cost. These advantages make them an ideal substitute for CdSe quantum dots in backlit display devices. As a kind of nanoparticles with a localized surface plasmon resonance effect, Au can be effectively used to enhance the photoluminescence of perovskite nanocrystals (NCs). In this study, Au nanoparticles were introduced into a borosilicate glass system with CsPbBrI 2 NCs to improve the optical properties. A series of Au@CsPbBrI 2 NCs glasses with tunable wavelengths in the range of 628–640 nm was successfully prepared. The photoluminescence quantum yield (PLQY) of the CsPbBrI 2 NCs glass was increased from 15% to 68% with the addition of AuBr 3. The Au@CsPbBrI 2 NC glass showed good aqueous, thermal, and blue light stabilities. Additionally, a backlight conversion film prepared by compounding the Au@CsPbBrI 2 NC glass powder exhibiting the optimal properties with polymethylmethacrylate (PMMA), was applied to a liquid crystal display (LCD). The presented image were more saturated and richer. Our results show that the optimized sample has immense potential for practical applications in the field of backlit displays. [Display omitted] • The fluorescence intensity of CsPbBrI 2 nanocrystals is increased by nearly 5 times, and PLQY is increased from 15% to 68%. • While Au@CsPbBrI 2 @glass has excellent water stability and blue light stability, the stability of Au@CsPbBrI 2 @glass@PMMA is further improved. • Large-scale production of optical conversion films can be achieved. [ABSTRACT FROM AUTHOR]

All-inorganic perovskite quantum dots (QDs) have become a hot material in the field of photoelectricity due to their excellent properties, such as high photoluminescence quantum yields (PLQYs), narrow emission wavelengths, and easily controlled PL spectra and particle sizes. However, colloidal perovskite QDs are readily oxidized, degraded in a humid environment, and generated by ion exchange. Here, the CsPb 1-X Sn X Br 2 I QDs were synthesized successfully, which the Sn2+ ions partly replacing Pb2+ to reduce the toxicity of Pb-based perovskite. The tunable PL spectrum and band gap from 2.27 to 2.14 eV were obtained by adjusting the Sn content. Meanwhile, we adopted a simple, green and low-cost approach to encapsulated CsPb 1-X Sn X Br 2 I QDs within solid paraffin, which not only greatly improved the water stability of QDs, but also maintained outstanding luminous intensity after being immersed in water for 20 days. Finally, the while light-emitting diodes (WLEDs) with varying correlated color temperature (CCT), color rendering index (CRI) and luminous efficiency (LE) based on a combination of blue chip, P–CsPb 1-X Sn X Br 2 I QDs and red phosphor were successfully achieved. Low toxicity CsPb 1-x Sn x Br 2 I QDs encapsulated in paraffin with tunble band gap, photoelectric properties and stable for WLED. Image 1 • CsPb 1-X Sn X Br 2 I QDs with tunable band gap and luminescence characteristics were successfully synthesized. • The low toxicity CsPb 1-X Sn X Br 2 I QDs were encapsulated in solid Paraffin. • The as-prepared samples shown excellent water-resistant and presented potential applications in WLED. [ABSTRACT FROM AUTHOR]

Abstract CsPbX 3 perovskite nanocrystals (NCs) are still limited in their use due to their extreme instability in the air as they will deteriorate in a few days, and their thermal stability is not optimistic. In this study, the red CsPbBr x I 3-x (X = 1.5, 1.0, 0.8, 0.5, 0.35, 0) NCs and Mn-doped CsPbBr x I 3-x NC in zinc borosilicate (B 2 O 3 -SiO 2 -ZnO) glass with cubic perovskite crystal structure were successfully synthesized through melt-quenching and heat-treatment method, which exhibited strong red emission in region of 572 nm–708 nm under 365 nm excitation. Additionally they are stable in the air for several months while showing excellent thermal stability. It is worth mentioning that Mn-doped CsPbBr x I 3-x NC glasses are brighter than CsPbBr x I 3-x NC glasses under UV light. Because Mn-doped CsPbBr x I 3-x NC glasses have good thermal and air stability, they can be used as a red fluorescent material. We fabricated glass with Y 3 Al 5 O 12 :Ce3+ (YAG:Ce3+) phosphor-in-glass (PiG) realized the chromaticity tuning for YAG:Ce3+ phosphor with white light-emitting-diodes (WLED). Highlights • Mn-doped CsPbBr x I 3-x NC glass with a strong red fluorescence. • The glass maintains the cubic perovskite crystal structure like NCs. • By changing the ratio of halogen, the emission band was tuned from 572 nm to 708 nm. • The glass overcomes the air instability and poor water resistant properties. • The glass can used as red phosphor and stacked on the Ce-PiG to achieve warm WLED. [ABSTRACT FROM AUTHOR]

Abstract In recent times, white-light emitting diodes (W-LEDs) have been widely used as light sources. However, most of the commercial lamps lack the red-light component. Herein, study on a novel blue-light activated alkaline earth ion doped Mn4+:Y 3 Al 5 O 12 (Mn4+:YAG) phosphor, exhibiting a strong red emission that is attributed to the Mn4+: 2E g →4A 2g spin-forbidden transition in the 650–750 nm spectral region, that can be excited by both near-ultraviolet and blue chips is presented. The dopants Be2+, Mg2+, Sr2+, and Ba2+ were found to be significantly beneficial for enhancing Mn4+ luminescence, the related mechanism is systematically discussed here. In addition, the concentration quenching is systematically investigated. The crystal field strength (Dq) and the Racah parameters (B and C) are carefully calculated. After incorporating Mn4+/Be2+:YAG phosphors (glass ceramics) and GaAG phosphors into a blue LED device, white light with a high color rendering index and a low correlated color temperature is successfully obtained. Therefore, the Mn4+/Be2+:YAG phosphor can serve as color converter for application in W-LED. Highlights • Luminescence of Mn4+YAG red phosphor was enhanced via alkali earth ion doping. • Mn4+/Be2+YAG GC was prepared via low temperature co-sintering technique. • Mn4+/Be2+YAG phosphors and GaAG phosphors into a blue LED device. [ABSTRACT FROM AUTHOR]

To achieve efficient phosphors that address the shortage of red emission for use in white light emitting diodes (WLED), a series of red-emitting phosphors of Sr 2 MgGe 2 O 7 doped with different concentrations of Mn 4+ have been successfully fabricated by a high-temperature solid-state method. The crystal structure properties including the phase purity were analysed by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Absolute quantum yield, temperature stability, and lifetime were utilized to characterize the samples. Furthermore, the excitation spectra of the samples exhibit two broad absorption bands with peaks located at approximately 308 nm and 419 nm, which could be excited by near-UV/blue LED light. The emission spectra range from 600 nm to 700 nm and exhibited a sharp peak at 659 nm due to the 4 E→ 4 A 2 spin- and parity-forbidden transition of Mn 4+ . The optimal Mn 4+ doping concentration in the Sr 2 MgGe 2 O 7 host is determined to be 0.7%. The critical energy transfer distance of these phosphors is calculated to be about 26.61 Å, and the concentration quenching mechanism is proved to correspond to a dipole-dipole interaction. The luminescence of the Sr 2 MgGe 2 O 7 :Mn 4+ phosphors decrease gradually with increasing temperature, and the Sr 2 MgGe 2 O 7 :Mn 4+ sample exhibits better thermal stability than the commercial Sr 2 Si 5 N 8 :Eu 2+ red phosphors. The warm WLED is fabricated by combining the Sr 2 MgGe 2 O 7 :0.7%Mn 4+ and YAG:Ce 3+ phosphor with a 420-nm blue LED chip to explore its possible applications in warm WLED. [ABSTRACT FROM AUTHOR]

Metal-halide perovskites have been hailed as remarkable materials for photovoltaic devices and, recently, their star has also been on the rise in optoelectronics and photonics. Nevertheless, challenging issues, such as the thermal/chemical stability and high-performance devices with long-term stability, limit their practical applications. Here, we successfully prepared CsPbBr 3 NCs incorporated into mesoporous silica (NCs-MS) by a simple stirred of MS with CsPbBr 3 NCs blended in toluene solution. The resultant NCs-MS nanocomposite exhibit excellent optical performance and good thermal and photostability under illumination of UV light for 120 h. Additionally, NCs-MS nanocomposite is resistant to water, which are beneficial for the fabrication of white light-emitting diode (WLED) devices. Thereby a WLED was constructed by combining NCs-MS nanocomposite with Sr 2 Si 5 N 8 :Eu 2+ red phosphor on an InGaN blue chip, achieving a highly efficient luminous efficacy of 47.6 lm/W. Moreover, the WLED also demonstrate wonderful color stability under 120 mA current. This work opens up the exciting opportunity of using all-inorganic CsPbBr 3 NCs-MS nanocomposite for high performance and low-cost WLEDs applications. [ABSTRACT FROM AUTHOR]

The formation of cesium lead halide perovskite nanocrystals are very effortless due to its extremely fast reaction kinetics. Herein, we present simple hot-inject approach and anion exchange reaction to fabricate all inorganic colloidal CsPbX 3 perovskite nanocrystals (NCs). The colloidal CsPbX 3 NCs with controlling-size exhibit the characteristics of the high luminescent intensity, superior quantum yields (QY, above 69%) and the narrow-band emission tuning, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 425–710 nm. Moreover, the third-order nonlinear optical properties of all inorganic colloidal perovskite nanocrystals (CsPbCl 3 , CsPbBr 3 , CsPbI 3 ) were measured using the Z-scan technique, indicating excellent third-order optical nonlinearities. Nonlinear optical susceptibilities reaching to 3.78 × 10 −11 esu for CsPbBr 3 NCs, figure of merit is achieving above 5 for CsPbI 3 NCs. These interesting results demonstrate that the as-prepared all inorganic colloidal CsPbX 3 perovskite nanocrystals are expected to hold great promise for application on nonlinear optoelectronic devices. [ABSTRACT FROM AUTHOR]

Laser lighting technology has become a new star in the field of modern lighting. However, the thermal quenching of optical conversion materials occurs at high incident power density, so it is an urgent problem to improve their heat resistance. In this paper, a kind of Lu 3 Al 5 O 12 :Ce&CaAlSiN 3 :Eu2+ (LuAG&CASN) composite phosphor-in-glass (PiG) suitable for high power laser diode is prepared, which shows high brightness and high display. In addition, the graphene monolayer grown by chemical vapor deposition (CVD) is coated on the surface of LuAG&CASN-PiG to further improve the luminescence performance of PiG. The saturation power threshold of the graphene-PiG (G-PiG) sample can reach 4.5 W and the maximum output lumen flux can reach 317.95 lm when the system is excited with 450 nm blue light using the reflective structure. Compared with the samples without graphene coating, the luminescence efficiency of G-PiG was improved by 23.2%. This single-layer graphene surface coating method provides a new idea for the preparation of high-performance fluorescence conversion materials for laser lighting applications, which may play an important role in the future laser lighting. • Adding CASN phosphor, the chromogenic index of the sample was improved. • A single layer of graphene was coated on the surface of LuAG&CASN-PiG composites. • The graphene-PiG sample has a saturation power threshold of 4.5 W and a maximum output lumen flux of 317.95 lm. • Compared with the samples without graphene coating, the luminescence efficiency of G-PiG was improved by 23.2%. [ABSTRACT FROM AUTHOR]

In this work, poly-crystalline CaCuO 2 /CaCu 2 O 3 thin films were deposited on quartz substrates using radio frequency (RF) magnetron sputtering and subsequent annealing. The deposition process was performed at room temperature under an oxygen partial pressure of 4 × 10 −2 Pa at a speed of 2 Å/s. The crystalline structure, distribution of the particles and size of the elements of the as-prepared and CaCuO 2 /CaCu 2 O 3 thin films were individually acquired and discussed in detail. Subsequent annealing was found to modify the composition, structure and morphological characteristics of the as-prepared thin film, resulting in changes of the film quality and, thereby, improving the nonlinear optical (NLO) response of the film. The sign and magnitude of third-order nonlinear susceptibility χ (3) of the as-prepared and CaCuO 2 /CaCu 2 O 3 thin films were determined using the top-hat Z-scan technique performed at 532 nm with a laser duration of 190 fs. The results show that annealed CaCuO 2 /CaCu 2 O 3 thin film exhibits a fast NLO response with a third-order nonlinear susceptibility χ (3) of 1.1 × 10 −12 esu, which is higher than that of the as-prepared thin film. The results indicate that CaCuO 2 /CaCu 2 O 3 thin films have potential applications in nonlinear optics. [ABSTRACT FROM AUTHOR]

Currently, the non-rare-earth Mn 4+ -activated oxide red phosphor is of great interest as color converter for warm white light-emitting diodes (W-LEDs), owing to its admirable luminescent properties and low price. Herein, a novel blue-light activated Ca 14 Zn 6 Ga 10 O 35 :Mn 4+ (CZG:Mn 4+ ) phosphor, exhibiting strong red emission attributed to Mn 4+ : 2 E g → 4 A 2g spin-forbidden transition in region of 650–750 nm under 462 nm excitation, is successfully synthesized through a traditional solid-state reaction route in air. Subsequently, the microstructure and luminescent performance of this red-emitting phosphor are discussed in detail. The crystal field strength ( Dq ) and the Racah parameters ( B and C ) are carefully calculated to estimate the nephelauxetic effect of Mn 4+ suffering from the CZG host lattice. In addition, the concentration quenching and thermal quenching characteristics are also systematically investigated. After incorporating CZG:Mn 4+ and commercial Y 3 Al 5 O 12 :Ce 3+ (Ce:YAG) phosphors into a blue LED device, warm white light with high color rendering index and low correlated color temperature is successfully achieved. Therefore, the CZG:Mn 4+ phosphor can serve as color converter for use in warm W-LED applications. [ABSTRACT FROM AUTHOR]

Glass containing metal nanoparticles (NPs) is a promising candidate for application in nonlinear optical devices. Hence, transparent sodium borosilicate (NBS) glass incorporated into NiO nanoparticles (NPs) was fabricated by sol-gel processes plus a controlled atmosphere. Fourier transform infrared (FTIR) analysis was applied to identify the formation mechanism of the NBS glass network. X-ray powder diffraction (XRD), Transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS) analysis were performed to confirm that spherical and well dispersed NiO NPs did exist in the glass host. Z-scan technique was used to investigate third-order nonlinear optical properties (NLO) of the as-obtained glass in the femtosecond (fs) and picosecond (ps) regimes. The results revealed that the glass displayed no nonlinear absorption and moderately strong self-focusing performance in the fs regime, while it exhibited a reverse saturable absorption (RSA) effect in the ps regime. [ABSTRACT FROM AUTHOR]

In recent years, the success of laser lighting and display technology depends on the comprehensive properties of light conversion materials such as thermal stability and luminous efficiency. Therefore, fluorescent glass has become the main research object due to its outstanding comprehensive properties such as simple preparation and high quantum efficiency. In this study, a kind of Na 2 O-K 2 O-SrO-MgO-CaO-Al 2 O 3 -B 2 O 3 -SiO 2 glass matrix was carefully designed to reduce the damage of Y 3 Al 5 O 12 :Ce3+(Ce:YAG) phosphor in the compounding process. This glass component not only has a low melting point, but also has a high thermal conductivity. More importantly, Ce:YAG phosphor-in-glass (Ce:YAG-PiG) prepared by mixing the optimized glass powder with Ce:YAG phosphors has high thermal conductivity and luminescent properties. Under the excitation of 460 nm blue light, the quantum efficiency of Ce:YAG-PiG can reach 84.8%, which is 91.8% of that of the phosphors (92.4%). When the temperature is below 225 ℃, the thermal conductivity of the sample can be kept above 2.0 Wm−1K−1. Particularly, without any heat dissipation measures, the sample can withstand 3.15 W/mm2 blue laser radiation, and the luminous flux (LF) is 517.83 lm. The results show that this Ce:YAG-PiG composite material can be used for ultra-high brightness laser illumination, which will have a good application prospect. • High-performance Ce:YAG-PiG was synthesized by well-designed glass matrix and Ce: YAG phosphors. • The excellent IQE of Ce:YAG-PiG is as high as 84.8 %, which keeps good optical performance. • The optimized Ce:YAG-PiG keeps the thermal conductivity of 1.9 Wm−1k−1 at 275 ℃ without any heat dissipation measures. • Ce:YAG-PiG can withstand an incident power density of 3.15 W/mm2 and achieve an ultra-high luminous flux of 517.83 lm. [ABSTRACT FROM AUTHOR]

Highly luminescent AgInS 2 –ZnS quantum dots were obtained by a one-pot two steps hot injection approach. The effect of the reaction time on the properties of the quantum dot was systematically investigated. By the introduction of Zn ions, the emission peak was blue-shift from 638 nm to 584 nm in 15 min, while the emission peaks of the obtained AgInS 2 –ZnS quantum dots were tuned in a narrow range with a bit red-shift from 584 to 589 nm as the reaction was continued. The highest photoluminescence quantum yield (PL QY) was up to about 72% when the reaction was prolonged to 15 min. Further, results showed that the morphologies were varied as the reaction was continued. In addition, the PL decay curves demonstrated that the component of PL bands resulted from Zn doping was observed, while the PL behavior was originated from the donor-acceptor recombination. [ABSTRACT FROM AUTHOR]

Lanthanide doped hexagonal β-NaGdF 4 nanocrystals embedded transparent bulk glass ceramics were successfully fabricated via a phase-separation-controlled crystallization route. Elemental mapping in the scanning transmission electron microscope and optical spectroscopy analysis demonstrated the partition of the active centers into the β-NaGdF 4 crystalline lattice. As a result, upconversion luminescence of the glass ceramic co-doped with Yb 3+ and Er 3+ is about 60 times as high as that of the precursor glass, attributing to the modification of Yb 3+ /Er 3+ surrounding from phase-separated amorphous nanoparticle to β-NaGdF 4 crystalline lattice with low phonon energy and high crystallinity after crystallization. Furthermore, the temperature-dependent green upconversion emissions assigned to 2 H 11/2 → 4 I 15/2 (520 nm) and 4 S 3/2 → 4 I 15/2 (540 nm) transitions were investigated, and the corresponding fluorescence intensity ratio of these two thermally coupled emitting-states greatly enhanced with increase of temperature. Using such fabricated glass ceramic as an optical thermometric medium, the maximum sensitivity reached as high as 0.0037 K −1 at 580 K. It is expected that the investigated Er 3+ /Yb 3+ codoped glass ceramic might be a very promising candidate for accurate optical temperature sensors. [ABSTRACT FROM AUTHOR]

Highlights: [•] The CuGaS2 quantum dots doped sodium borosilicate glass was prepared by sol–gel methods. [•] The obtained glass was investigated by XRD, (S)TEM and XPS. [•] Tetragonal crystalline phase of CuGaS2 quantum dots with spherical shape were formed uniformly in the glass matrix. [•] The third-order optical nonlinearity was investigated by Z-scan technique. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Pb nanoparticles embedded in Na2O–B2O3–SiO2 glass were prepared by sol–gel methods. [•] The crystal phase and composition of glass were characterized by XRD, EDS and XPS. [•] The morphology and microstructure were measured by TEM. [•] The formation mechanism of the glass was investigated. [•] The third-order optical nonlinearity was investigated by using Z-scan technique. [Copyright &y& Elsevier]

Highlights: [•] Monodisperse CIS NCs have been obtained via thermal decomposition of metal–thiolate. [•] The XRD pattern revealed that CIS NCs have chalcopyrite and wurtzite structures. [•] Pyramid-like (chalcopyrite) and nanospheres (wurtzite) were determined by TEM. [•] The third-order optical nonlinearity is investigated by using Z-scan technique. [Copyright &y& Elsevier]

Highlights: [•] The quantum yield of the obtained ternary AgInS2 QDs was up to 62% with the emission peak of 642nm under the excitation of 460nm. [•] Colorful luminescent Ag–Zn–In–S QDs were obtained by adding Zn salts directly as well as Ag and In precursors. [•] The obtained highly luminescent quantum dots showed promising applications in the white light emitting diodes (W-LED). [•] The electroluminescence (EL) of AgInS2 QDs was observed in QD-LED device. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Cu2In nanoparticles doped in Na2O–B2O3–SiO2 glass were prepared by sol–gel methods. [•] Microstructure of Cu2In nanoparticles was investigated by XRD, EDS and TEM. [•] The third-order optical nonlinearity was investigated by using Z-scan technique. [Copyright &y& Elsevier]

Abstract: The In2S3 quantum dots embedded in sodium borosilicate glass matrix was prepared using both sol–gel and atmosphere control methods. According to the results of X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectrum, high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED), In2S3 quantum dots in tetragonal crystal system have formed uniformly in the glass, and the size distribution of these quantum dots generally ranged from 12 to 20nm. The third-order optical nonlinearity of In2S3 quantum dots doped sodium borosilicate glass was investigated by Z-scan technique. The value of χ (3) was estimated to be 1.16×10−12 esu at 800nm. [Copyright &y& Elsevier]

Abstract: The growth of Mn-doped YAG:Ce (yttrium aluminum garnet doped cerium) single crystal by the Czochralski (CZ) method and the characterization of its spectroscopy and color-electric parameters are presented. The absorption spectra indicate that the crystal absorbed highly in the 300–500nm wavelength range. The emission spectrum of the crystal consists of a peak around 538nm when excited by 460nm blue light, which prove the YAG:Ce,Mn single crystal could be used in the white light emitting doides (LED). The different charges of Mn ions have different luminescence properties, and the air annealing process for the single crystal would change the concentration of Mn ions with different charges, which could influence the emission intensity of the single crystal. [Copyright &y& Elsevier]

Abstract: Copper quantum dots embedded in sodium borosilicate glass matrix were fabricated and analyzed in terms of their structural, chemical, and optical properties. X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses revealed that copper quantum dots were in face-centered-cubic crystalline phase and in the metallic state. Size and distribution of the quantum dots were measured by transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM). The results showed spherical shape have formed uniformly in the glass, and the size of these quantum dots were range from 1.5 to 5nm with the average particle size about 2.7nm. The third-order nonlinear optical properties of copper quantum dots doped glass were investigated by using Z-scan technique at the wavelength of 800nm with femtosecond Ti: sapphire laser radiation. The value of third-order optical nonlinear susceptibility χ (3) of the glass was estimated to be 2.41×10−11 esu. [Copyright &y& Elsevier]

Abstract: A mild biomolecule-assisted route for preparation of flower-like AgBiS2 crystals was developed via reactions among AgNO3, BiCl3, and l-cystine in N,N-dimethylformamide (DMF) at 200°C for 12h. l-cystine was used as both the sulfide source and complexing agent. The as-synthesized AgBiS2 crystals were characterized by XRD, EDS, XPS, PL, FESEM, TEM, HRTEM, and SAED. Results showed that the synthesized AgBiS2 crystals had stoichiometric composition, good crystallinity, and flower-like morphology. A possible formation mechanism for flower-like AgBiS2 crystals was also discussed based on the experiment. [Copyright &y& Elsevier]

Abstract: The sodium borosilicate glass containing Bi2S3 nanocrystals is prepared by employing both sol–gel and atmosphere control methods. The third-order nonlinear optical absorption of the glass is investigated in detail using the open-aperture Z-scan technique at the wavelength of 770nm with a pulse width of 200fs. The results show that the transformation from saturable absorption to reverse saturable absorption in the glass is observed with the increase of the input light intensity of the laser used. The mechanism of the third-order nonlinear optical absorption is discussed preliminarily in the glass. Meanwhile, XRD, XPS, TEM, (S)TEM, EDAX, HRTEM, and SAED are used to characterize the microstructures of the glass. [Copyright &y& Elsevier]

Abstract: Flowerlike cubic beta-indium (III) sulfide (β-In2S3) microspheres were synthesized via a one-step solvothermal route, in which thiosalicylic acid (TSA) and carbon disulfide (CS2) were used as the double sulfur sources. The phase structure, morphology and composition of the products were characterized by means of X-ray powder diffraction (XRD), field-emission scanning microscopy (FESEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The thermal behavior and the optical properties were investigated by thermogravimetric (TG) measurements and UV–vis spectrophotometer, respectively. Furthermore, the role of TSA was studied by the Fourier transform infrared spectroscopy (FTIR), and a possible mechanism for the growth of the flowerlike cubic β-In2S3 microspheres was proposed. [Copyright &y& Elsevier]

Abstract: 5.74Na2O–21.38B2O3–72.88SiO2 glasses doped with semiconductor 1% wt PbS nanocrystals were fabricated via a sol–gel route. The formation of PbS nanocrystals in the glass matrix was proven by X-ray photoelectron spectroscopy (XPS). The HRTEM images showed that the PbS crystals existed as nanocrystals with a narrow distribution diameter at 3.5nm. Furthermore, Fast Fourier transformation (FFT) demonstrated the existence of PbS with face-centered cubic (FCC) structure. Comparing with the bulk PbS, the absorption edge in the optical absorption spectra of the glass doped with PbS nanocrystals exhibited a blue shift with an obvious quantum size effect. The glass had a nonlinear refractive index (γ) of −2.03×10−14 cm2/GW and a nonlinear absorption coefficient (β) of 7.05×10−10 cm/GW) based on Z-scan technique measurement. [Copyright &y& Elsevier]

• β-Sialon-PiG have been successfully prepared and hold a good thermal stability. • β-Sialon-PiG has a high internal quantum efficiency of 72% after synthesis. • Under the 450 nm blue laser, higher luminous efficiency of 154 lm/W was obtained. • A high threshold of 363 lm of lumen flux was obtained for the sample under laser. [Display omitted] With the high demand of modern people for lighting quality, higher requirements have been put forward for the lighting technology. Compared with traditional light emitting diodes (LEDs), laser diode (LD)-driven lighting technology has more prominent advantages in the fields of industry, military and life. Here, we report a phosphor-in-glass (PiG) material formed by co-firing commercial β-Sialon:Eu2+ phosphor and SiO 2 -Na 2 CO 3 -H 3 BO 3 -CaO (SNBC) glass. It is found that the powder perfectly dispersed in the glass without obvious interface reaction. Fluorescence intensity of PiG sintered at 800 °C is the strongest, and the position of the luminescence peak is around 540 nm. Then through the analysis of different concentrations of PiG phosphors, it is found that the internal quantum efficiency (IQE) can reach 72%. The specific heat capacity decreases with the increase of temperature, indicating that the heat dissipation effect is fine. Under the blue LD irradiation of 450 nm, the luminous flux of the PiG sample reaches 363 lm and the high luminous efficiency of 154 lm/W. Our research found that the prepared β-Sialon-PiG can provide green light for high-power laser illumination and is a stable and efficient fluorescent conversion material. [ABSTRACT FROM AUTHOR]

Abstract: A novel biomolecule-assisted method has been successfully developed to prepare pyrargyrite (Ag3SbS3) nanorods via the reactions between AgNO3 and SbCl3 with l-cystine in ethylene glycol at 200°C for 15h, in which l-cystine was used as the sulfide source and complexing agent. The crystal phase, morphology, grain size, and chemical composition of the as-prepared products were characterized in detail by X-ray powder diffraction (XRD), energy dispersion spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). Results revealed that the as-synthesized Ag3SbS3 nanorods had diameters range from 150 to 200nm and lengths up to several micrometers. The experimental results showed that the reaction time played an important role in the formation of Ag3SbS3 nanocrystalline. A possible formation mechanism for Ag3SbS3 nanorods was discussed. [Copyright &y& Elsevier]