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In this study, we propose a new design strategy that introduces unique mixed-anion AgSxCly ligands into thiophosphate to afford a successful synthesis of a promising Ag5PS4Cl2 IR NLO chalcohalide. Compared with chlorine-free Ag3PS4, Ag5PS4Cl2 undergoes overall performance enhancement and achieves a good balance between large NLO effect (2.0 × Ag3PS4) and high laser damage threshold (3.8 × Ag3PS4). Theoretical analysis further indicates that AgSxCly groups are the new superior NLO-active units since they can maintain the wide bandgap while concurrently making a great contribution to the origin of NLO effects. Therefore, the incorporation of AgSxCly groups into the crystal structure can be expected to be one feasible way to design new IR NLO candidates with excellent performance. [ABSTRACT FROM AUTHOR]

Lanthanum hexaaluminate is a promising candidate to establish yttria partially stabilized zirconia as a thermal barrier coating material for super alloy due to their remarkable stability and thermophysical performance. In order to understand the relationship between the structure and properties and gain new low thermal conducting materials, the LnMgAl11O19 (LnMA, Ln: La, Pr, Nd, Sm, Eu, Gd) materials were synthesized firstly and further used to produce the LnMA ceramics. With the increasing relative atomic mass of the replaced Ln3+ ions from La to Gd, the lattice parameters and grain sizes of the LnMA platelets decrease, while the mechanical properties increase, and the thermal physic properties decrease. The GdMgAl11O19 ceramics obtain the lowest thermal conductivity with the value of 1.91‐1.78 W/m K in the range from room temperature to 800°C, which could be considered as a promising candidate for application in thermal barrier coating materials. These results could further provide reference for developing novel materials lower thermal conductivity. [ABSTRACT FROM AUTHOR]

• Y 3 LiGeS 7 and Y 3 Cd 0.5 GeS 7 were successfully synthesized for the first time. • Optical performances of title crystals were systematically investigated. • All of them exhibit large SHG responses with requisite phase-matching behavior. • SHG-density and dipole moment calculation analyze the origin of NLO effect. [Display omitted] Combination of multiple structural groups was developed as one effective method for regulating material property and exploring new nonlinear optical (NLO) crystals. For that reason, four Ln 3 MGeS 7 (Y 3 LiGeS 7 , Y 3 Cd 0.5 GeS 7 , Gd 3 Cd 0.5 GeS 7 and Sm 3 Zn 0.5 GeS 7) crystals with various structural motifs were successfully synthesized and systematically investigated. Note that Y 3 LiGeS 7 and Y 3 Cd 0.5 GeS 7 were firstly synthesized so far. Performance test shows that Ln 3 MGeS 7 compounds exhibit the variable optical bandgaps (1.62–2.33 eV) and good second harmonic generation (SHG) responses (0.7–1.1 × commercial AgGaS 2) with requisite phase-matching behavior, which agree well with the theoretical results (Y 3 LiGeS 7 : Δ n = 0.058 and d 33 = 19.97 pm/V; Y 3 Cd 0.5 GeS 7 : Δ n = 0.055 and d 33 = 20.6 pm/V) and introduction of MIIB (Zn, Cd) atoms into crystal structure is conducive to enlarge the SHG effect. SHG density and dipole-moment calculations indicate that their SHG effects are originated from the major contribution on LnS n units with moderate effect of GeS 4 and MIIBS 6 (Zn, Cd) ligands. Therefore, selecting appropriate functional motifs (LnS n and MIIB) into crystal structure can promote the enhancement of NLO property and further realize the rational design of new promising infrared NLO materials. [ABSTRACT FROM AUTHOR]

The development of white-light-emitting diodes (w-LEDs) makes it meaningful to develop novel high-performance phosphors excited by blue light. Herein, BiOCl:Pr3+ green-yellow phosphors were prepared via a high-temperature solid-state reaction method. The crystal structure, luminescent properties, lifetime, thermal quenching behavior, and quantum yield were studied in detail. The BiOCl:Pr3+ phosphors presented several emission peaks located in green and red regions, under excitation at 453 nm. The CIE coordinates could be tuned along with the changed doping concentration with fair luminescence efficiency. The results also indicated that the optimized doping concentration of Pr3+ ions was at x = 0.0075 because of the concentration quenching behavior resulting from an intense exchange effect. When the temperature reached 150 °C, the intensity of the emission peak at 495 nm could remain at 78% of that at room temperature. The activation energy of 0.20 eV also confirmed that the BiOCl:Pr3+ phosphor exhibited good thermal stability. All these results indicate that the prepared products have potential to be used as a high-performance green-yellow-light-emitting phosphor for blue-light-based w-LEDs. [ABSTRACT FROM AUTHOR]

Two quaternary metal chalcogenides, Ba2AlSbS5 and Ba2GaBiSe5, were successfully synthesized by solid-state reaction in sealed silica tubes. Both of them crystallize in the same orthorhombic space group Pnma, but they appear with obviously different construction features. For example, Ba2AlSbS5 exhibits [SbS3]3− units and zero-dimensional (0D) [AlSbS5]4− clusters, which is different from those ([BiSe6]3− units and 1D ∞[GaBiSe5]4− chains) of Ba2GaBiSe5. We also systematically investigated the entire series of Ba2MIIIMIII’Q5 (MIII = Al, Ga, In; MIII’ = As, Sb, Bi; Q = S, Se, Te) compounds, and the results showed that the interconnection of MIIIQ4 and MIII’Qn (n = 3, 5, 6) units can form three different structural types, including 0D [MIIIMIII’Q5] clusters, single [MIII’Q3] chains and isolated [MIIIQ4] units, or [MIIIQ3]n and [MIII’Q3]n double chains, which may be induced by the flexible coordination and on-link modes of MIII’ atoms. Spectral investigation shows that their bandgaps are about 2.57 eV for Ba2AlSbS5 and 2.14 eV for Ba2GaBiSe5. Theoretical calculation was also used to analyze their structure-property relationships, and the results indicate that the title compounds exhibit larger birefringences (Δn > 0.10), thus having potential as the IR birefringent materials. [ABSTRACT FROM AUTHOR]

The single-component BiOCl:Dy3+ white-light-emitting phosphor was successfully prepared. The luminescence performance with excellent thermal stability indicated that this as-prepared product could act as a high-performance phosphor candidate for n-UV w-LED application. • The single-component BiOCl:Dy3+ phosphor was prepared successfully. • The phosphor emitted white light under the excitation in n-UV light region. • The PL properties obtained excellent thermal stability at higher temperatures. • The phosphor could have great potential for n-UV w-LED application. The advantages of single-component white-light-emitting phosphor make it more important for n-UV-light emitting diodes with excellent properties and efficiency. Herein, the BiOCl:Dy3+ white-light-emitting phosphor was firstly prepared by high temperature solid-state reaction. And the crystal structure, luminescence properties, lifetime, and thermal quenching behavior were carried out in detail. The results revealed that the BiOCl:Dy3+ phosphor could be excited efficiently in a broad near ultraviolet (n-UV) light region, which matched well with the n-UV chips for w-LEDs. Under the excitation at 390 nm, the BiOCl:Dy3+ phosphor exhibited white light with three emission peaks centered at 481, 575, and 664 nm, respectively. The optimal doping concentration of Dy3+ ions was found to be x = 0.03, and exchange interaction was confirmed to result in the concentration quenching. Furthermore, when the test temperature turned up to 150 °C, the intensity of emission peaks at 481 and 575 nm could still remain 77.96% and 77.93% of the initial intensity at room temperature. With the their activation energy of 0.33 eV and 0.27 eV, the excellent thermal stability of the BiOCl:Dy3+ phosphor were confirmed. All these results indicated that this as-prepared product could act as a high-performance phosphor candidate for n-UV w-LED application. [ABSTRACT FROM AUTHOR]

The Eu 3+ ion activated pyrochlore-type La 2 Zr 2 O 7 red emitting phosphor was prepared through solid-state reaction. The electronic structure of La 2 Zr 2 O 7 was investigated with density functional theory (DFT) calculation. The phase purity, crystalline structure, morphology and lattice parameters of the Eu 3+ ion doped La 2 Zr 2 O 7 through powder X-ray diffraction and Rietveld refinement were also elucidated in details. The as-prepared La 2 Zr 2 O 7 : Eu 3+ phosphors presented excellent red light emission with intense absorption bands in the near-ultraviolet and blue light regions. The optimized doping concentration of Eu 3+ ions was found to be 0.05 with an ideal CIE coordinate index of (0.62, 0.38). Finally, the excellent thermal stability of La 2 Zr 2 O 7 : Eu 3+ phosphor was also determined according to the temperature dependent emission spectra, excited at 393 nm. All these results indicated that the La 2 Zr 2 O 7 : Eu 3+ phosphors had high potential for applications in solid-state white light-emitting diodes as suitable red-emitting components for white light emitting diodes (w-LEDs), combined with near-ultraviolet or blue lighting chips. [ABSTRACT FROM AUTHOR]

A new family of rigid periodically zigzag structure of TiN 1 + x and columnar TiN 1 + x rods were synthesized by a vapor–liquid–solid deposition method, using iron as the catalyst and milled TiO 2 /Al powders as the starting material. Fundamental mechanism studies based on interface thermodynamics and surface tension were conducted in order to understand the formation of the near-perfect periodically zigzag structure. Four-terminal electrical measurements showed that the single crystalline rods yielded very different resistances due to their nonstoichiometric characteristics. The conductivity of the TiN 1 + x rods could be affected by insulating-type electric field. The results indicated that TiN-based nano-rods have a big potential for application in electric scopes. [ABSTRACT FROM AUTHOR]

A series of apatite-type phosphors Ba 4.97− x Sr x (PO 4 ) 3 Cl:Eu 2+ ( x = 0, 0.5, 1.0, 1.5, 2.0) were synthesized by the high temperature solid-state reaction method, and its luminescence properties were investigated in detail. It can be found that a red shift of the emission peak wavelength emerged from 439 to 462 nm with the continuous introduction of Sr 2+ into the crystal lattice which has been simulated by a crystal-field model. The red shift is explained by the distortion in the crystal structure through X-ray diffraction and the Rietveld refinement analysis. According to a recently raised structural model, Eu 2+ ions are surrounded by O atoms, PO 4 tetrahedrons and Ba/Sr ions. After introducing Sr 2+ into the lattice, the interatomic distance between Ba/Sr atoms and Eu 2+ was expected to become shorter, resulting in a distortion of the inner EuO n polyhedrons. Then the crystal field strength surrounding Eu 2+ was increased, finally resulting in the red shift. [ABSTRACT FROM AUTHOR]

Ca 2 TiMnO 6 compounds were synthesized by the conventional solid-state reaction in air. The crystal structure and magnetic properties were investigated. Characterization of X-ray diffractions and the refinement analysis confirmed the orthorhombic (space group Pbnm) structure of Ca 2 TiMnO 6 at room temperature. Magnetic measurements reveal that the double perovskite Ca 2 TiMnO 6 has antiferromagnetic interactions at low temperature and a paramagnetic order above 40 K. According to the Curie–Weiss fitting at high temperature, the Neel constant θ p and experimental efficient moment μ eff was estimated to be about −161.98 K and 4.91 μ B , respectively. The theoretical efficient moment was calculated to be 3.87 μ B . The XPS analysis indicates that the difference between experimental and theoretical efficient moment caused by the mixed valence state of Mn in Ca 2 TiMnO 6 . The temperature dependence of coercivity field shows a soft magnetic property in Ca 2 TiMnO 6 oxides. The mechanism of the low temperature anomaly which was appeared in magnetization curve was discussed in detail. [ABSTRACT FROM AUTHOR]

Cyan-emitting LiBaBO 3 :Eu 2+ phosphor was synthesized by solid-state reaction at 800 °C. Structure refinement by Rietveld method reveals that LiBaBO 3 crystallizes in a monoclinic cell, space groups P 2 1 / c or P 2 1 / n . Upon 365 nm excitation, LiBaBO 3 :Eu 2+ shows a symmetric emission band peaking at 496 nm with full-width at half-maximum of 80 nm; when monitoring at 496 nm, a broad excitation band in the UV region (250–420 nm) is observed. The luminescence property of LiBaBO 3 :Eu 2+ is considerably different from LiSrBO 3 :Eu 2+ which holds the same space group. The local structures of the two hosts are compared to explain the different behaviors of Eu 2+ . [ABSTRACT FROM AUTHOR]

An orange reddish emitting phosphor, LaMgAl 11 O 19 :Sm 3+ , was synthesized by a high temperature solid-state reaction, and the phase formation, crystal structure and luminescence properties were investigated respectively. The LaMgAl 11 O 19 :Sm 3+ phosphor presents a highly intense orange reddish emission peak under the near ultraviolet excitation at 403 nm, which is corresponds to the 4 G 5/2 → 6 H J ( J = 5/2, 7/2, 9/2 and 11/2) transitions of Sm 3+ ions. It was found that the dipole–dipole interactions mainly results in the concentration quenching in the LaMgAl 11 O 19 :Sm 3+ phosphor with a critical quenching concentration at about 5 mol%. The temperature dependence of luminescence properties was studied from 25 to 200 °C and indicated that LaMgAl 11 O 19 :0.05Sm 3+ phosphors had a relatively higher quenching temperature. The chromatic properties of LaMgAl 11 O 19 :0.05Sm 3+ phosphor have been found to have chromaticity coordinate of (0.578, 0.420). All these properties indicate that the orange reddish emitting LaMgAl 11 O 19 :Sm 3+ phosphor has a potential application in w-LEDs. [ABSTRACT FROM AUTHOR]