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Chalcogenides with high ionic conductivity and appropriate mechanical properties are promising solid‐state electrolytes (SSEs) to substitute current liquid electrolytes in lithium‐ion batteries. Yet, their practical applications in all‐solid‐state batteries are still retarded by both the low critical current density and the inferior interfacial stability toward electrodes. In this work, a series of superior SSEs, that is, Li2S‐P2S5‐B2S3 electrolytes, are developed via a ball‐milling and then melt‐quenching strategy. These SSEs exhibit a high critical current density of 1.65 mA cm−2 and a long cycling life of over 300 h. In addition, the evolution mechanism of the interphase between SSEs and metallic lithium is revealed via operando electrochemical impedance spectroscopy, depth‐profiling XPS, and in situ Raman spectroscopy. The structural and chemical heterogeneities are found to be the main origins of the continual interphase evolution. The resulting "multi‐layer mosaic like" interphase facilitates the suppression of Li dendrite growth, and hence, prolongs the lifetime of lithium‐ion all‐solid‐state batteries. In addition, the preparation technique of SSEs developed in the present work is feasible for scale‐up production. [ABSTRACT FROM AUTHOR]

Fiber‐based inorganic thermoelectric (TE) devices, owing to the small size, light‐weight, flexibility, and high TE performance, are promising for applications in flexible thermoelectrics. Unfortunately, current inorganic TE fibers are strictly constrained by limited mechanical freedom because of the undesirable tensile strain, typically limited to a value of 1.5%, posing a strong obstacle for further application in large‐scale wearable systems. Here, a superflexible Ag2Te0.6S0.4 inorganic TE fiber is demonstrated that provides a record tensile strain of 21.2%, such that it enables various complex deformations. Importantly, the TE performance of the fiber shows high stability after ≈1000 cycles of bending and releasing processes with a small bending radius of 5 mm. This allows for the integration of the inorganic TE fiber into 3D wearable fabric, yielding a normalized power density of 0.4 µW m−1 K−2 under the temperature difference of 20 K, which is approaching the high‐performance Bi2Te3‐based inorganic TE fabric and is nearly two orders of magnitude higher than the organic TE fabrics. These results highlight that the inorganic TE fiber with both superior shape‐conformable ability and high TE performance may find potential applications in wearable electronics. [ABSTRACT FROM AUTHOR]

Infrared gradient refractive index (GRIN) lenses have great application value and potential in multispectral imaging systems. This study reports various chalcogenide axial GRIN glasses prepared using the hot‐pressing diffusion method. It is worth noting that the S4–S60 GRIN sample has a difference in refractive index (RI) Δn of greater than 0.3 and a diffusion depth of about 5 mm, which is the deepest diffusion depth reported in chalcogenide glass to date. In addition, the linear portion in the profile of the GRIN sample has a RI difference of 0.15 and a thickness of 1.2 mm. The effects of the temperature, concentration difference, and diffusion time on the sample diffusion process are discussed. The dispersion properties of the GRIN samples were further calculated, providing a new option for correcting chromatic aberrations in optical systems. In addition, a method for the indirect nondestructive characterization of sample RI using the Raman intensity ratio is proposed, and the reliability of the method is verified by practical experiments, which is convenient for the subsequent measurement of the GRIN profile. [ABSTRACT FROM AUTHOR]

Mid‐infrared (mid‐IR) on‐chip photonic devices have attracted increasing attention because of their potential applications in chemical and biological sensing and optical communications. In particular, chalcogenide glasses (ChGs) have long been regarded as promising materials for mid‐IR integrated photonics, owing to their broad infrared transparency, high nonlinearity, and excellent processing capabilities. Here, an inverse design approach is introduced to ChG photonic device design with a new robust inverse design method. A high‐performance mid‐IR inverse design polarization beam splitter, waveguide polarizer, mode converter, and wavelength demultiplexer are demonstrated for the first time. They all have a footprint of only several micrometers. The robust inverse design method could improve the robustness of device performance against fabrication variations and would be a general approach for designing and optimizing miniaturized chalcogenide photonic devices. [ABSTRACT FROM AUTHOR]

An amorphous superionic conductor is a promising solid electrolyte (SE) with excellent ionic conductivity and high energy density, which would be promising candidates for all‐solid‐state lithium‐ion batteries. However, these advantageous features alone are difficult to achieve large‐scale practical applications. Having a simple, effective synthetic route and good air stability is also critically important for SEs. Here, Li3PS4–xLiBr glass SE with high conductivity was obtained by simple mechanical milling and subsequent short‐term low‐temperature treatment. The site disorder between S2− and Br− anions facilitates ionic transport. Our comparison of air stability before and after doping with halogen revealed that Br− doping well reduced the production of H2S gas and improved the air stability of the SE. [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 acousto‐optic parameters of Ge10As90−xTex (x = 30, 40, 50, 60, 70 mol%) and Ge10As20Te70−ySey (y = 20, 30, 40, 50 mol%) glasses, were studied systematically to compare the pros and cons of Te‐based and Se‐based chalcogenide glasses in acousto‐optic performance, as well as the thermomechanical properties. In the Ge10As90−xTex system, the acousto‐optic figure of merit (M2) increased with increased Te content, and the maximum M2 of 2279 × 10−18 s3/g, which is 13 times that of commercial single‐crystal Ge, obtained in Ge10As20Te70 at 10.6 μm. However, its thermal properties and elastic modulus decreased and the acoustic attenuation (α) at different ultrasonic frequencies increased accordingly. In the Ge10As20Te70−ySey system, the thermomechanical performance of the glasses improved with the introduction of Se element, the overall α was lower than that of Te‐based chalcogenide glasses, and the minimum α was 5.29 dB/cm at 30 MHz ultrasonic frequency, although its M2 was inferior to that of Te‐based chalcogenide glasses. Additionally, the difference in the α of these glasses was smaller at low ultrasonic frequencies than at high ultrasonic frequencies. This work will promote the practical application of chalcogenide glasses as promising materials with outstanding acousto‐optic properties in low ultrasonic frequency acousto‐optic devices. [ABSTRACT FROM AUTHOR]

Ion‐conducting chalcogenide glass is a promising solid electrolyte with excellent conductivity and energy density for all‐solid‐state batteries. A suitable ionic channel for carriers in the amorphous network is urgently needed. In this work, the structural evolution of co‐doped metal cations (Ge and Ga) in the glass matrix and its influence on electrochemical behavior were studied using a series of GexGa16‐xSb64S128‐40AgI glass samples. The macroscopic properties of samples were examined by X‐ray diffraction (XRD), differential scanning calorimetry (DSC), and Raman tests. The electrochemical behavior of samples was investigated by AC impendence spectroscopy and cyclic voltammetry (CV) measurement. Furthermore, a deliquescence experiment was applied for the chemical stability test of glass samples. The ionic conductivity of samples was developed by adding Ga components. Notably, the electrochemical window of electrolytes was remarkably wide at approximately 5 V. The resistance of samples to humidity was characterized by the decreased Raman peaks. Analysis results show that the Ga‐related bonding structure evidently increased the chemical stability compared with the non‐Ga sample. This work provides an insight into the effective and stable ions transport, especially in the Ge(Ga)SbS glass system. These results promote the further investigation of sulfide solid electrolytes and practical application of all‐solid‐state batteries. [ABSTRACT FROM AUTHOR]

By conventional melt‐quenching techniques, a series of Dy3+‐doped (0.1 to 1.0 wt%) Ga5Ge20Sb15S60 bulk glasses were fabricated and their potential for developing mid‐infrared fiber laser beyond 4 μm were evaluated, in which the optimal Dy3+ doping concentration was found to be 0.3 wt% and the largest laser quality factor value (σe × τmea = 2.62 × 10−23 cm2 s) among all of the Dy3+‐doped chalcogenide glass was obtained. On this basis, through using the chemical purification methods with chlorine gas combined with the dynamic distillation process, the high‐purity GGSS glasses with low O–H and S–H absorptions were successfully fabricated, which was confirmed by the optimized mid‐infrared linear transmittance and improved fluorescent lifetimes of Dy3+: 6H13/2, 6H11/2 levels. Furthermore, for the first time to the best of our knowledge, the Dy3+‐doped, single‐mode, and double‐cladding chalcogenide fibers with the core/cladding ratios of 125:60:11 and 125:66:11.5 were achieved by a multistage rod‐in‐tube fiber drawing process and extrusion methods, respectively. The GeS2‐based fiber exhibits excellent transmission performance at 1.0‐5.0 μm: 3.0 dB/m at 2.9 μm (O–H), 2.4 dB/m at 4.1 μm (S–H). Combining the advantages of high‐purity, high doping concentration and single‐mode double‐cladding structure, the optimized active fiber should be an ideal efficient and low‐threshold medium toward mid‐infrared fiber laser beyond 4 μm. [ABSTRACT FROM AUTHOR]

The design of functional materials with tunable broadband luminescence performance is still of great interest in the fields of lighting, solar cells, tunable lasers, and optical amplifiers. Here, via a melt‐quenching method, a series of bismuth (Bi)‐doped germanium‐borate glasses with composition of 40GeO2–25B2O3–25Gd2O3–10La2O3–xBi2O3 have been prepared, in which multiple Bi active centers can be stabilized simultaneously. Dual‐modulating modes of visible (380‐750 nm) and near‐infrared (NIR) (1000‐1600 nm) broadband photoemissions were effectively controlled under flexible excitation scheme. Photoluminescence (PL) spectra at low temperature 10‐298 K were appropriately employed to interpret such an unusual wide visible emission band. To further illustrate the origin of NIR component, transmission electron microscopy (TEM) measurement was carried out. It is demonstrated experimentally that the visible emission mainly originates from the collective contribution of the 3P1/3P0→1S0 transitions of Bi3+, while the broadband NIR luminescence should be related to the formation of low valent Bi+ and (or) Bi0 centers. This work may help to enhance the knowledge of the complex luminescence mechanism for the Bi species and it also enables such transparent glass materials to be a promising candidate for the multifunctional tunable light source. [ABSTRACT FROM AUTHOR]

Ge–As–Se chalcogenide glasses were prepared and the surface damage characteristics under femtosecond laser irradiation were experimentally investigated. Femtosecond laser beams with different power intensities, focusing depths, pulse repetition rates, and pulse numbers were employed to determine the damage thresholds of the samples. The surface morphologies and feature sizes of the damage craters were studied with regard to laser energy density to evaluate the damage circumstances of the glasses. The generation of the surface damage was also recorded by using different numbers of pulses. Results showed that the damage area increased monotonically with the laser power at low energy density and tended to saturation when reaching a critical value. According to the linear circumstances of laser energy density on the damage crater area, the average damage thresholds of the Ge–As–Se glasses with different repetition rates and pulse numbers were obtained. Results showed that the damage threshold decreased with the increase in pulse repetition rate and number of pulse. [ABSTRACT FROM AUTHOR]

AgI‐based Ge–Sb–S, Ga–Sb–S, and Ge–Ga–Sb–S chalcogenide glasses were designed and prepared by melt‐quenching, thereafter their thermal properties and conductive performance were comparatively investigated on the basis of their composition‐induced network structures. Glass transition in each sample was examined by DSC measurements. Results showed that the samples containing Ge had a higher thermal stability than the Ga–Sb–S–AgI sample, and the Ge–Sb–S–AgI sample obtained had the highest conductivity ion. Raman spectrum analysis was performed, and the results indicated that the [GeS4‐xIx] structural units and [SbS3−xIx] pyramids in the matrix produced effective ion transport channel for dissolved conductive Ag+ ions. In the matrix containing Ga, the [Ga(Ge)S4‐xIx] structure was consumed by part of [S3Ga–GaS3] ethane‐like units, which had no contribution to the ion transition framework. The study provided the directions for composition and structure configuration control in effective conductive chalcogenide glasses. [ABSTRACT FROM AUTHOR]

Cr2+‐doped II‐VI crystals have witnessed an excellent gain media for continuously tunable and femtosecond‐pulsed lasers. Despite this, major challenges persist toward realizing ultrabroad emission bandwidth and efficient Cr2+‐doped fiber due to the valence diversity of Cr, especially in chalcogenide glasses. Here, we propose to prepare Cr2+:ZnSe/As2S3‐xSex composite glasses by Hot Uniaxial Pressing (HUP), a method that sinters uniformly mixed crystal and glass powders into geometrically designed composite chalcogenide glasses. The densification of the composite glasses reached 99.88%, indicating that a few or none pores remain. Our research shows that Cr2+:ZnSe crystals have good performance in chalcogenide glasses, and the composite glasses have the potential to be made into mid‐infrared–doped fibers. It was demonstrated by scanning electron microscopy (SEM) and X‐ray diffraction (XRD) that the composite glasses have a uniform Cr2+:ZnSe distribution and no crystal disintegration. The transmittance of the composite glasses was significantly improved by tailoring the refraction index. The mid‐infrared (MIR) fluorescence and decay of the glasses were measured. The lattice constant was measured, calculated, and discussed to reveal the influence of sintering process on lifetime. [ABSTRACT FROM AUTHOR]

High nonlinear fibers with low zero‐dispersion wavelength (ZDW), high laser power tolerance and large band‐gap are urgent for all‐optical‐band supercontinuum (SC) generations. Widely used chalcogenide fibers usually have a large ZDW and low laser power tolerance, and thus are not ideal for such purpose. Here, an ultra‐low material ZDW chalcohalide (ChH) glass fiber with high nonlinearity as well as high laser power tolerance has been fabricated successfully via a novel peeling‐off‐extrusion method. The step‐index fiber has double‐cladding structure, the inner cladding is GeGaSe‐CsI glass and the outer one is GeSbS jacket. The core glass has an ultra‐low material ZDW of 3.5 μm and large absorption edge of 2.0 eV. The nonlinear refractive index is 6.67 × 10−18 m2/W @1.55 μm. Broadband SC generation covering 1.05‐13.0 μm is demonstrated in this novel ChH fiber. Such glass fiber with high nonlinearity, wide transparent range, low ZDW and high laser damage threshold is promising for the applications in the mid‐infrared. [ABSTRACT FROM AUTHOR]

The microhardness of chalcogenide glasses (ChGs) of the Sn–Sb–Se (SSS) ternary system was investigated, and the correlation of microhardness with the mean coordination number of the SSS ChGs was determined. To prepare infrared‐transparent SSS glass‐ceramics (GCs), two SSS ChGs (A, Sn6.23Sb14.11Se79.66; B, Sn9.8Sb17.22Se72.98; by molar composition) were selected and thermally treated at 433 and 448 K, respectively. The improved microhardness (with values that increased by 11.5% and 7.3% for SSS ChG A and B, respectively) of the resulting SSS GCs is attributed to the formation of Sb2Se3 nanocrystals. [ABSTRACT FROM AUTHOR]

The glass‐ceramics of AgI‐based electroconductive chalcogenide system was realized using an appropriate heat treatment at a fairly high temperature (Tg + 40°C) and different times ranging from 4 to 20 hours. The crystallization behavior and electroconductive properties of the heat‐treated samples were studied in detail. Transmission study was performed, and the results show that the cut‐off edge of the short wavelength is red‐shifted at prolonged annealing time but remains an excellent transmittance in the mid‐infrared (IR) region. XRD and scanning electron microscopy results indicated that the precipitated crystalline phases are mainly β‐/γ‐AgI. Moreover, a small amount of α‐AgI, which rarely existed at room temperature, is precipitated in the AgI‐rich chalcogenide glass‐ceramics. The ionic conductivity of all glass‐ceramics was enhanced by heat treatment in contrast to that of base glass. Raman analysis exhibited the structure variation in the glass sample after heat treatments. This study provided an observation of crystallization in chalcogenide glass containing large amounts of AgI and be of good guidance to fabricate novel AgI‐based chalcogenide glass‐ceramics that can be candidates in infrared optics and solid electrolyte applications. [ABSTRACT FROM AUTHOR]

A novel family of Ga2S3-Sb2S3-XI (XI = PbI2, CsI, AgI) was investigated to understand the role of metal halides and exploit new chalco-halide glasses for infrared optics. The dependence of the thermal properties, infrared optical properties, and structural information of the novel family on different metal-iodines was investigated. Results showed that metal halides increase the glass stability but decrease the glass network connectivity. The compositional dependence of the short-wave cut-off edge is associated with the electronegativity difference between the cations and anions of the metal halides. Raman study showed that the metal- iodine modified the glass structure mainly through the iodide content, and the cations dissolved in the glass network mostly as charge compensators for the aperiodic network. For the glasses in the series Ga2S3-Sb2S3-XI-Dy3+, Dy3+ emission increased in the PbI2- and CsI-doped glasses but decreased in the AgI-doped glass due to the combined effect of dysprosium and oxygen. For all that, these novel glasses are highly promised for use in infrared optics. [ABSTRACT FROM AUTHOR]

A mid-infrared (MIR) supercontinuum (SC) has been demonstrated in a low-loss telluride glass fiber. The double-cladding fiber, fabricated using a novel extrusion method, exhibits excellent transmission at 8-14 μm: < 10 dB/m in the range of 8-13.5 μm and 6 dB/m at 11 μm. Launched intense ultrashort pulsed with a central wavelength of 7 μm, the step-index fiber generates a MIR SC spanning from ∼2.0 μm to 16 μm, for a 40-dB spectral flatness. This is a fresh experimental demonstration to reveal that telluride glass fiber can emit across the all MIR molecular fingerprint region, which is of key importance for applications such as diagnostics, gas sensing, and greenhouse CO2 detection. [ABSTRACT FROM AUTHOR]

A systematic investigation of the optical and structural properties of chalcogenide glasses in Ge-Sn-Se ternary system is presented. We have found a threshold behavior of optical property, namely, existence of transitional composition of the Ge-Sn-Se glasses, with progressive replacement of Se by Sn. Calculation of mean coordination number indicates that the transition-like feature of optical property is associated with the evolution of chemical ordering of the Ge-Sn-Se network. Analysis of Raman spectra of the glasses explains that the interaction between Se-Se bonds, Sn(Se1/2)4 tetrahedra, and Sn-Sn homopolar bonds is the origination of such optical phenomenon. [ABSTRACT FROM AUTHOR]

Glass-ceramics of PbS-doped 80 GeS2·20 Ga2 S3 were fabricated by heat treatments of base glasses at Tg+30°C for different durations. They exhibited improved mechanical properties such as hardness and resistance to crack propagation, and meanwhile retained their excellent infrared transmission. X-ray diffraction and Raman results indicated that Ga2 S3 and GeS2 crystals were precipitated inside glassy matrix. The crystallization kinetics of base glass was investigated using differential scanning calorimetry under nonisothermal conditions. Compared with the previous work concerning on 80 GeS2·20 Ga2 S3 glass, there exists some different features of crystallization behavior. Such variation is discussed and correlated with the network structure and crystallization kinetics in this glass system. [ABSTRACT FROM AUTHOR]

Materials containing rare-earth ions and Ag nanoparticles ( NPs) have been widely applied due to prior demonstration of increase in their luminescence properties. Here, Tm3+ ions-doped bismuth germanate glasses were synthesized by a chemical reduction method based on the conventional melting-quenching technique. The Ag NPs were facilely precipitated in the glass matrix by the chemical reduction method during the annealing process. TEM image shows that the Ag NPs are closely dispersed in the glass matrix. The luminescence properties and energy-transfer mechanism were systematically investigated by means of absorption, emission, and excitation spectra. Significant enhancements of Tm3+ ions emission and a broad emission band centered at 568 nm caused by Ag NPs are observed upon 474-nm excitation. Our research may illustrate the interactions between Tm3+ ions and Ag NPs and provide a simplified way to synthesize the high-efficiency luminescent materials for the blue light-excited W- LEDs. [ABSTRACT FROM AUTHOR]

A series of (1 − x) GeS2.5 - x Sb chalcogenide glasses were prepared using the conventional melt-quenching method. Their microstructure and thermal response were systematically studied. We observe a compositional threshold of x = 0.25 which corresponds to chemical stoichiometric composition in the calorimetric experiments. It is in good accordance with the Raman scattering results and laser-induced phase transformation behavior. They also indicate that phase separation of Sb-rich phase exists in the S-poor samples. Moreover, we got a structural modeling of this phase separation: (1) at x = 0.25, which is chemical stoichiometric composition, the structural motifs are only SbS3 pyramid and GeS4 tetrahedra, and the three-coordinated SbS3 pyramid is isolated by GeS4 tetrahedra; (2) at x < 0.25, the S- S bonds exist in the glass network due to the excess of S; and (3) at x > 0.25, the excess of Sb break the Ge- S and Sb- S bonds to form Sb( Ge)- Sb Bonds, and the Sb atoms segregate from the backbone to nucleate a separate Sb-rich phase. This work provides a new way to investigate the phase separation of glass networks and helps us to better understand their related physical properties. [ABSTRACT FROM AUTHOR]

Diagram of the phase transformation behavior of GeS2- Ga2 S3- CsI glasses is realized in this article and the structure-property dependence of the chalcogenide glasses is elucidated using differential scanning calorimetry and Raman spectroscopy. We observe the compositional threshold of crystallization behavior locates at x = 6-7 mol% in (100− x)(0.8 GeS2-0.2 Ga2 S3)- x CsI glasses, which is confirmed by the thermodynamic studies. Structural motifs are derived from the Raman result that [ Ge( Ga) S4], [ S2 GeI2], [ S3 GaI], and [ S3 Ga- GaS3] were identified to exist in this glass network. Combined with the information of structural threshold, local arrangement of these structural motifs is proposed to explain all the experimental observations, which provides a new way to understand the correlation between crystallization behavior and network structure in chalcogenide glasses. [ABSTRACT FROM AUTHOR]

In this work, SRO thin films were prepared by magnetron sputtering and converted to Si nano-crystals (Si-NCs) by rapid thermal annealing (RTA). Further tube-furnace annealing was performed on the Si-NC films in order to reduce residual stress. The residual stress in the Si-NC thin films after RTA at 1100 and 1200 °C were determined as 2.41 and 1.87 GPa, respectively, and the following tube-furnace annealing can obviously decrease the residual stress. The residual stress decreased with increasing annealing temperature and time. The following tube-furnace annealing at 1100 °C for 60 min and 1000 °C for 180 min reduced the residual stress to 1.46 and 1 GPa, respectively, for the Si-NC thin films with prior RTA at 1200 °C. The reduction of residual stress was ascribed to the larger density of extended defects and the lower surface-to-volume ratio of the thin films. [ABSTRACT FROM AUTHOR]

Enhanced luminescence in rare-earth-doped chalcogenide glass-ceramics is of great interest for the potential integrated optoelectronic devices. However, fundamental mechanism on the enhancement of luminescence upon crystallization remains largely unknown. We report the fabrication and characterization of wide transmission chalcogenide glass and glass-ceramics based on the 25 GeS2·35 Ga2 S3·40 CsCl:0.3 Er glass composition, and discuss the mechanism of enhanced luminescence. By monitoring the 4 I9/2-4 I15/2 of Er3+ transition, up-conversion luminescence of 12 times higher was observed in glass-ceramics compared with that in base glass. Electron paramagnetic resonance (EPR) and Raman scattering spectroscopies were employed to obtain the information of selective environment of Er3+ ions and microstructural evolution with the crystallization progress. Both of them evidenced that the enhanced up-conversion luminescence was mainly related to the local environmental evolution from a mixed chlorine-sulfur coordination to a low phonon energy chlorine coordination in the residual glassy matrix of glass-ceramics. [ABSTRACT FROM AUTHOR]

Glass-ceramics of 80 GeS2·20 In2 S3 were fabricated by heat-treating the base glass at 402°C ( Tg + 30°C) for different durations. The glass-ceramics exhibited some improved mechanical properties such as hardness and resistance to crack propagation, and meanwhile remained an excellent infrared ( IR) transmission. The XRD and Raman results showed that only In2 S3 crystals were precipitated inside glassy matrix. The evolution of two crystallization peaks ( CPs) in differential scanning calorimeter ( DSC) curves were studied with samples heat-treated at 402°C for different durations. It was found that the precipitation of In2 S3 crystal phase is responsible for the low-temperature (first) CP, whereas the high-temperature (second) CP shifts to a higher temperature with the elongation of the heat-treatment duration. The crystallization of the higher temperature phase was inhibited with the precipitation of In2 S3. Furthermore, crystallization mechanism was investigated using the nonisothermal method. The computed results showed that strictly more energy (higher activation energy, Ec) is essential for the precipitation of the higher temperature phase, which is in accordance with the DSC study of crystallized samples. More noticeable, the crystallization rate constant ( K) value of 6.639 × 10−8 s−1 for the second CP is ~ 5 orders of magnitude smaller than that of the In2 S3 phase, and this significant difference makes the crystallization of higher temperature crystal phase very hard. Consequently, controllable crystallization of 80 GeS2·20 In2 S3 chalcogenide glass-ceramics with sole In2 S3 crystallites can be achieved easily. [ABSTRACT FROM AUTHOR]

54 GeS2-36 Sb2 S3-10 In2 S3 glass-ceramics were prepared by heat-treating the base glass above Tg for different durations. The results of Raman spectra and XRD patterns show that the first precipitated crystals during the heat treatment are In2 S3 and the crystallization of the Sb2 S3 and GeS2 subsequently occurs. Bulk samples heat-treated at 295°C for different heating rates and durations are used to study the crystallization mechanism and evolution of the three crystallization peaks (CPs). It is found that three CPs partly overlap with each other and then separate with increasing heat-treating durations. [ABSTRACT FROM AUTHOR]