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All‐solid‐state sodium‐ion batteries (NIBs) are emerging as a strong contender to the widely used lithium‐ion batteries due to their abundant resources and high safety performance. Solid‐state electrolytes, as the key component of SSBs, have gained widespread attention for their high safety and chemical stability. This study presented a novel solid glass‐ceramic electrolyte, Na3Sb0.75As0.25S4, which was synthesized by high ball milling and heat treatment. The findings demonstrate that elemental As can have a dual effect of improving ionic conductivity and successfully lowering H2S gas emission. Na3Sb0.75As0.25S4 exhibits superior performance in the cubic phase due to the partial replacement of Sb by As, with ionic conductivity up to 2.42 mS/cm and a low activation energy of 0.119 eV at room temperature. Furthermore, it releases only 0.017 cm3/g H2S in a conventional humidity environment for 30 min, much lower than the amount of 0.05 cm3/g H2S released by undoped Na3SbS4, making it an excellent candidate for all‐solid‐state NIB electrolyte. [ABSTRACT FROM AUTHOR]

Solid Na‐ion‐conducting sulfides exhibited potential applications for commercial solid‐state rechargeable batteries because of their low cost and good contact with the electrode. In the present work, a sulfide sodium‐ion conductor 2Na3SbS4·Na2WS4 with a conductivity of 1.55 mS cm−1 was obtained, which was identified as superior to the 2Na3SbS4·Na4XS4 (X = Si, Ge, Sn) systems. Further exploration of the heat treatment to improve the crystallinity of the glass resulted in a high conductivity of 1.9 mS cm−1 and low activation energy of 0.24 eV for the 2Na3SbS4·Na2WS4 glass–ceramic electrolyte. The high crystallinity after heat treatment at 380°C facilitated the migration of Na+ together with large sodium vacancies formed by doping with W6+ in 2Na3SbS4·Na2WS4 glass–ceramic electrolyte, resulting in the improved electrochemical performance. In addition, the air stability of the 2Na3SbS4·Na2WS4 glass–ceramic electrolyte decreased monotonically with increase of the annealing temperature, and heat application at 380°C effectively improved the electrolyte tolerance to the air compared with pure Na3PS4 electrolyte. The origins of aliovalent ion doping and thermal effect on the electrochemical performance were discussed in detail. [ABSTRACT FROM AUTHOR]

High ionic conductivity, low grain boundary impedance, and stable electrochemical property have become the focus for all‐solid‐state lithium–sulfur batteries (ASSLSB). One of the approaches is to promote the rapid diffusion of lithium ions by regulating the chemical bond interactions within the framework. The structure control of P5+ substitution for Sn4+ on lithium‐ion transport was explored for a series of Li3PS4–Li4SnS4 glass–ceramic electrolytes. Results showed that the grain boundary impedance of the glass electrolyte was reduced after heat treatments. The formation of LiSnPS microcrystals, a good superionic conductor, was detected by X‐ray diffraction tests. Electrochemical experiments obtained the highest conductivity of 29.5 S cm−1 at 100°C and stable electrochemical window from –0.1 to 5 V at 25°C. In addition, the cell battery was assembled with prepared electrolyte, which is promoted as a candidate solid electrolyte material with improved performance for ASSLSB. [ABSTRACT FROM AUTHOR]

The translation matching method (TMM) was presented here to obtain the refractive index (RI) of chalcogenide films more accurately. It solved the problem of calculation errors of the RI of the film that resulted from using the Swanepoel method after conventional treatments such as illumination, electrical measurement, and annealing. The TMM was suitable for calculating the RI of the film by calibrating the transmission spectrum regardless of whether it had been dealt with. The accuracy of the RI calculation is about 0.1% using the method. Experimentally, the method was used to obtain the RI of three chalcogenide films: they are original homogeneous film and RI nonuniform film treated by annealing and by femtosecond laser direct writing, respectively. The results showed that the decrease in the transmittance and weakened interference effect were effectively overcome and the RI of the three kinds of films was accurately obtained by using the method. This work should provide a useful guideline for obtaining the RI of the transparent optical films. [ABSTRACT FROM AUTHOR]

Through a careful composition design, new oxyfluoride glass-ceramics (GCs) containing BaLiF3 nanocrystals with sizes of around 30 nm were prepared. Microstructural characterizations show interpenetrating phase separation in the sample with a composition of 15BaF2-15ZnF2-70SiO2, after thermal treatment at 580°C for 40 h which leads to the nanocrystallization of BaLiF3. The BaLiF3 nanocrystals embedded in the glassy matrix could provide Ba or Li sites for the incorporation of optically active rare earth and transition-metal ions, which provides a possibility to explore novel photonic properties by the codoping of rare earth and transition-metal ions in GC materials. [ABSTRACT FROM AUTHOR]

transparent chalcogenide glass ceramics (ChGCs) based on a binary germanium-sulfur (Ge–S, GS) chalcogenide system were synthesized by heat treatment method. Compared with the precursor glass, the GS ChGCs embedded with GeS 2 nanocrystals have the same infrared transparency, but smaller optical bandgap energy and higher mechanical strength. Z-scan measurements show that third-order optical nonlinearity in the GS ChGCs was remarkably enhanced, and this material would be suitable for applications in optical limiting. [ABSTRACT FROM AUTHOR]

We demonstrate the modification of the third-order optical nonlinearity (TONL) of chalcogenide glasses (within the GeS 2 –In 2 S 3 –CsCl ternary system) by nanocrystallization, i.e., by controlling the precipitation of nanocrystals (in pure In 2 S 3 phase) within the amorphous background. Compared with the parent glass, the resultant chalcogenide glass ceramics (ChGCs) have unchanged infrared transmittance but modifiable optical bandgap energy with treatment duration. Both nonlinear refraction coefficient and nonlinear absorption coefficient of the ChGCs are increased due to the appearance of In 2 S 3 nanocrystals. ChGCs subjected to heat treatment for 1.3–2 h are found to exhibit the optimum TONL performance. [ABSTRACT FROM AUTHOR]

Abstract In this work, whole visible transparent chalcogenide glass ceramics (ChGCs) were prepared by heat treating a chalcohalide glass (with a molar composition of 20GeS 2 -35Ga 2 S 3 -45CsCl, GGC) for different time, and the formation of nano-crystals (NCs) belonging to the Ga 2 S 3 phase was identified. The femtosecond Z-scan technique was employed to observe, variations in the third-order optical nonlinearity (TONL) properties, especially the nonlinear refractive behaviour, due to the appearance of the Ga 2 S 3 NCs in the GGC glass network. The experimental results show that both sign and magnitude of the nonlinear refractive index (n 2 at 800 nm) changed as a result of the local field effect generated by the size-confined Ga 2 S 3 NCs. The maximum n 2 value obtained from the Ga 2 S 3 NCs was over 4 times that of the base glass and over 230 times to that of silica glass. [ABSTRACT FROM AUTHOR]

High-capacity and affordable all-solid-state Na-ion batteries have gathered increasing interest in recent years owing to low-cost sodium, which contributes to reducing the price of these Na-ion batteries to approximately 70% of that in lithium batteries. However, in terms of electrolyte performance and battery cost, the complete replacement of lithium batteries has a long way to go. In this work, low-cost and high-safety Na 2 S·9H 2 O materials are used in synthesizing Na 3 SbS 4 solid electrolyte, the price of which is only one-fifth that of high-purity Na 2 S. The structure and electrochemical properties are studied through X-ray diffraction analysis, Raman spectroscopy, scanning electron microscopy, and electrochemical tests. Results indicate that a multiphase Na 3 SbS 4 structure containing cubic and tetragonal phases formed after heat treatment at 300 °C. In addition, a third phase transition of Na 3 SbS 4 is inferred after further heating at 600 °C. This phase structure contributes to the improvement of electrochemical performance by promoting increasing ionic conductivity to 0.54 mS cm−1 at room temperature (25 °C) and reducing activation energy to 0.076 eV. This work provides an affordable material with good electrochemical properties and not only simplifies the preparation but also greatly reduces the risk of the process. [ABSTRACT FROM AUTHOR]

• The acousto-optic properties of chalcogenide glass ceramics are investigated firstly. • The highest M 2 of 189.43 × 10−18 s3/g was measured for chalcogenide glass ceramics. • The acoustic attenuation (α) value of chalcogenide glass ceramics is 9.17 dB/cm. • The studied glass-ceramic would be a new type of promising IR material for low-frequency acousto-optic devices. The acousto-optic (AO) characteristics of the 80GeSe 2 -20Ga 2 Se 3 chalcogenide glass and glass-ceramic (GC) samples at 10.6 μm is compared for the first time in this study. The thermomechanical performance and AO figure of merit M 2 (189 × 10―18 s3/g) of the GC sample are improved greatly compared with the corresponding base glass. The maximum M 2 value of the GC sample is ∼126 times greater than that of fused silica and ∼1.6 times greater than that of single-crystal germanium. A significant reduction in acoustic attenuation (5 dB/cm) is also observed. The micro-structural results indicated that, the precipitated Ga 2 Se 3 crystal grains and the tetrahedral structure in the residual matrix glass jointly reduced the acoustic attenuation of the glass ceramics with a heat treatment time of 15 h and improved the thermomechanical performance. This work suggests that chalcogenide glass-ceramic can be a new type of promising infrared AO material. [ABSTRACT FROM AUTHOR]

In comparison to narrow-band upconversion (UC) luminescence from lanthanide-doped systems, broadband UC emission enables a broad and tailorable emissive color, which is desirable for tunable lasers and multicolor display applications. Herein, dual continuous broadband UC emission covering the visible spectral region at 480–720 nm has been achieved for the first time in Yb3+/Mn2+ co-doped glass ceramics (GCs) functionalized with the precipitation of dual-phase γ -Ga 2 O 3 / β -YF 3 nanocrystals. A tunable UC emissive color from yellowish to orange could be obtained under 980 nm excitation by varying the Mn2+ doping content and heat treatment temperature of GCs. We ascribe this phenomenon to the typical transition of exchange-coupled Yb3+-Mn2+ dimers in tetrahedral and octahedral ligand environments. The Stokes and power-dependent UC luminescence properties, fluorescence lifetimes, site occupation and the involved UC mechanism are discussed in detail. This research contributes to a better understanding of the UC process between Yb3+ and Mn2+ in transparent hosts and provides a novel perspective for designing broadband-emitting UC materials. • Yb3+/Mn2+ co-doped transparent glass ceramics (GCs) containing γ -Ga 2 O 3 and β -YF 3 nanocrystals were prepared. • Dual continuous UC broadband emission covering 480~720 nm region has been achieved in this dual-phase system. • The GCs showed tunable UC emissive color from yellowish to orange by varying Mn2+ content and heat-treated temperature. [ABSTRACT FROM AUTHOR]

Mid-infrared (MIR) laser operating at 2–5 μm has gained increasing interest because of the extensive applications in fields from biomedicine, sensing to nanomaterial science. Chalcogenide glass (ChG) is a kind of matrix that is promising for MIR laser due to its low phonon energy and wide infrared transmittance region. However, significant challenges in the enhancement of MIR optical properties of rare-earth ion-doped ChGs still exist. Here, enhanced MIR emission was realized in Pr3+-doped chalcogenide glass ceramics (ChGCs). By controlling the heat treatment temperature and duration, biphasic-phase nanocrystals of Ga 2 Se 3 and GeSe 2 were successively precipitated in the glass host. Compared to the as-prepared glass, the GCs exhibit an obvious increase in emission intensity by more than 5 times. The improvement of the MIR emission may be induced by the enhanced cross-relaxation between Pr3+ ions and the increased multiple scattering effects. Furthermore, the obtained ChGC enables large stimulated emission cross section 0.42 × 10−20 cm2 at 2.44 μm and 0.62 × 10−20 cm2 at 4.75 μm. The superior optical properties of the ChGC indicate that it is an attractive candidate for MIR laser. • Biphasic-phase nanocrystals of Ga 2 Se 3 and GeSe 2 embedded glass-ceramic was prepared by controlled heat treatment. • Enhanced MIR emission of Pr3+ was observed in the glass ceramics. • Effect of biphasic-phase nanocrystals on the enhancement of MIR emission was investigated. • The glass-ceramic with large stimulated emission cross section endows its potential application in MIR laser. [ABSTRACT FROM AUTHOR]

Germanium (Ge)-sulfur (S) (GeS) binary system is a simple and green chalcogenide glass system. In this work, we prepared a Ge-rich non-stoichiometric GeS film and investigated its optical property and network structure. Findings show that improving or modifying the optical properties (optical transmittance, refractive index, etc.) of the GeS film with a one-step annealing process, and the structural evolution of GeS film network that is attribute to the annealing-induced property changing is identified. [ABSTRACT FROM AUTHOR]