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Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diopside-Like based ceramics as the main crystalline phase (expressed as 'Diopside') were prepared via one-step sintering using extracted titanium slag (ETS) and coal fly ash (CFA) as raw materials. The effects of CFA content and sintering temperature on the crystal phase composition, microstructure, properties and crystallization kinetics were studied by X-ray fluorescence, X-ray diffraction, scanning electron microscopy, and inductively coupled plasma emission spectrometry. According to the findings, the addition of CFA supplemented the deficiency of Si and Al in ETS and balanced the Ca/Al/Si molar ratio in the system. Moreover, at the CFA doping of 20 %, melilite was gradually transformed into 'diopside' at 800–1100 °C that further remained stable at 1160–1200 °C. 'Despite' the fact that the crystallization activation energy increased and the Avrami index was at its lowest level (1.75), the crystallization temperature was reduced, whereas the crystallization rate increased, causing the ceramic body and surface to crystallize and thereby improving the properties of ceramics. Sintering at 1180 °C for 1 h resulted in ceramics with 'diopside' as the primary crystal phase composition. The water absorption, linear shrinkage, bulk density, bending strength, and acid resistance were respectively 1.3 %, 13 %, 2.89 g cm−3, 141.8 MPa, and 97.36 %. Finally, 'diopside' possessed the higher acid resistance than melilite and anorthite. [ABSTRACT FROM AUTHOR]

High density (97 %) SiC ceramics containing in-situ synthesized Y 4 Al 2 O 9 (YAM) have been successfully fabricated by a novel PEP additive manufacturing technology combined with a one-step sintering method without any post-treatments. The process of additively manufacturing SiC green body, debinding and sintering has systematically studied. Meanwhile, the atomic structure of SiC and YAM was characterized, and the mechanical properties of sintered SiC ceramics were measured. The HRTEM results revealed the crystallographic orientation relationships between YAM and SiC as (0 4 0) YAM // (1 0 1 - 1) SiC and [1 0 2] YAM // [1 2 ¯ 1 0] SiC for the first time. The density, Vickers hardness and three-point bending strength of the sintered SiC samples are 3.11 g/cm3, 19.35 ± 0.28 GPa and 225 ± 27 MPa, respectively. Thus, PEP combined with the one-step sintering method provides a new strategy for complex-shaped SiC ceramics with high density and mechanical properties. [ABSTRACT FROM AUTHOR]

Cerium-doped gadolinium aluminum gallium garnet (Ce3+:Gd3Al3Ga2O12, Ce3+:GAGG) ceramic is a promising scintillation material. In this study, Ce3+:Gd3Al3Ga2O12 scintillation ceramics were prepared by the one-step sintering of commercially available Gd2O3, Al2O3, Ga2O3, and CeO2 powders in a flowing oxygen atmosphere at 1600 °C by solid-phase reaction sintering. For all the Ce3+:Gd3Al3Ga2O12 ceramic samples doped with different amounts of Ce3+ doping, dense ceramics were obtained. The structure, photoluminescence, and scintillation properties of the Ce3+:Gd3Al3Ga2O12 ceramics have been investigated. The average grain size of samples sintered at 1600 °C is about 2 μm. The X-ray excitation luminescence peak is around 560 nm, which is consistent with that of Ce3+:Gd3Al3Ga2O12 single crystals, matching well with the computed tomography X-ray detector's response sensitivity. The light yield is higher compared to the standard reference sample—lutetium yttrium orthosilicate single crystal. [ABSTRACT FROM AUTHOR]

Given the enormous need for cost-effective wall insulation materials in the developing countries and Nigeria specifically, this study, explores the viability of porous glass-ceramics production from granite dust and maize cob using one-step sintering technology. The chemical compositions of the locally sourced materials used including granite dust, ball clay and maize cob were obtained using XRF. 300µm of granite dust and ball clay as well as 425µm of maize cob powder were used. Different amount of granite dust and maize cob powder were mixed with constant amount of a mixture of NaOH and Na2SiO3 in three different groupings to formulate the porous glass-ceramics samples. The formulated samples were uniaxially pressed at 10MPa and sintered in a gas kiln at 850oC for 3 hours. The sintered samples were subjected to experimental tests. The results showed water absorption, apparent porosity, bulk density, compressive strength and thermal conductivity of 25.6%–46.7%, 43.5%–75%, 1.45g/cm3 –1.9g/cm3, 0.7MPa–9.7MPa and 0.11W/m.K–0.53W/m.K respectively. The mineralogical properties of the sintered samples were obtained using XRD. The results indicated a viable material for use in thermal insulation of residential buildings.

• SOFCs are prepared by a one-step co-pressing and co-sintering at 950 °C with Li-based sintering aids. • Low temperature co-sintering enables the application of nanoscaled materials with improved electrode kinetics. • The nanocomposite Ni-SDC and hierarchical SrNb 0.1 Fe 0.9 O 3 give sufficient electrode activity at intermediate-low temperature. • Electrolyte-supported SOFCs showed an OCV of 1.01 V at 500 °C and a peak power density of 291 mW cm−2 at 700 °C. Solid oxide fuel cells (SOFCs) require simple cell fabrication procedure and reduced sintering temperature to improve system economics and durability. In this work, we propose a one-step low temperature (950 °C vs. conventional ≥1300 °C) sintering technology to prepare doped ceria electrolyte-based SOFCs by adding 3 mol% of Li 2 O sintering aid. Super low temperature sintering grants the direct application of nanoporous Ni-based cermet anode and hierarchical SrNb 0.1 Fe 0.9 O 3 cathode with improved catalytic activities, which improves SOFC efficiency. The ionic conductivity of the electrolyte and catalytic activities of electrodes are systematically investigated by the electrochemical impedance spectroscopy technique and analyzed by the distribution of relaxation time method. These electrolyte-supported SOFCs exhibit an OCV value of 1.01 V at 500 °C and a peak power density of 291 mW cm−2 at 700 °C as well as sufficient stability for 50 h. Our results demonstrate a reliable and affordable method for manufacturing high-performance SOFCs. [Display omitted] [ABSTRACT FROM AUTHOR]

For the manufacturing of glass-ceramic products, a monolithic glass is prepared using the same technologies for the conventional glass production, followed by a thermal-treatment of nucleation and crystal growth. An alternative process could be the production of glass-ceramic materials by pressing of glass powders and densification by sintering. In this way, the same equipment used in a traditional ceramic tile plant could be used to produce components with complex geometry. In this work, the single-firing process was used to obtain LAS glass-ceramic (Li 2 O.Al 2 O 3.SiO 2) tiles. The aim of the work was to determine the effect of particle size, pressing and sintering temperature on the bending strength and thermal expansion coefficient of the glass-ceramic tiles. The raw materials were melted in alumina crucibles (1480 °C, 80 min) and the obtained glass was quenched in water and annealed (600 °C). The glass was milled for 1 and 2 h (ball mill), resulting in two particle sizes, 9.1 μm (1 h) and 22 μm (2 h). The powders were granulated and pressed at 35 and 45 MPa, resulting in four processing conditions. In sequence, the compacts were dried (150 °C, 24 h) and sintered at 1175 and 1185 °C (10 °C/min heating rate). The microstructure of the glass-ceramic tiles was determined by SEM and XRD techniques. The bending strength was determined by the 3-point method and the thermal expansion coefficient (CTE) was determined by dilatometry. As a result, LAS glass-ceramics tiles were obtained, showing high modulus of flexural strength (70–80 MPa) and very low thermal expansion coefficients (1.2–1.4 × 10−6 °C−1). Surface crystallization was achieved and the main phase was β-spodumene. Sintering was simultaneous to crystallization, in a typical one-step process. • LAS (Li 2 O.Al 2 O 3.SiO 2) glass-ceramic tiles with low thermal expansion processed by single-firing. • Glass-ceramic materials can be processed as tiles using conventional techniques. • LAS glass-ceramics with high modulus of flexural strength (70–80 MPa) and very low thermal expansion (1.2–1.4 10−6 °C−1). • Sintering simultaneous to crystallization resulting in spodumene microstructure. [ABSTRACT FROM AUTHOR]

Hole defects and uneven membrane thicknesses can lead to poor performance, especially in the separation stability of ceramic membranes. This paper uses a one-step sintering method, which avoids hole defects and uneven membrane thicknesses, for the preparation of high-performance and defect-free ceramic membranes. For this purpose, two kinds of ceramic membrane slurry with high or low viscosities were prepared by alumina particles, as raw materials. Both the effects of the two coating process with a one-step coating method for low-viscosity slurry, and the two-step coating method with a high viscosity flush after a low viscosity coating, on the surface properties of a ceramic membrane, were studied in detail. The result shows that the properties of ceramic membranes can be improved by a two-step coating method, with a high viscosity flush after a low viscosity coating, A high-performance and defect-free ceramic membrane was obtained by one-step sintering at 1450 °C for 2 hr with 7 wt % solid content and a coating time of 11 s. [ABSTRACT FROM AUTHOR]

Hole defects and uneven membrane thicknesses can lead to poor performance, especially in the separation stability of ceramic membranes. This paper uses a one-step sintering method, which avoids hole defects and uneven membrane thicknesses, for the preparation of high-performance and defect-free ceramic membranes. For this purpose, two kinds of ceramic membrane slurry with high or low viscosities were prepared by alumina particles, as raw materials. Both the effects of the two coating process with a one-step coating method for low-viscosity slurry, and the two-step coating method with a high viscosity flush after a low viscosity coating, on the surface properties of a ceramic membrane, were studied in detail. The result shows that the properties of ceramic membranes can be improved by a two-step coating method, with a high viscosity flush after a low viscosity coating, A high-performance and defect-free ceramic membrane was obtained by one-step sintering at 1450 °C for 2 hr with 7 wt % solid content and a coating time of 11 s.

In this work, the interlayer and top-layer of alumina membrane are synthesized on substrate by one-step sintering process, and the microstructure evolution and mass transfer characterization of top-layer synthesized from sub-micrometer spheres is fully investigated. It shows that the pores in top-layer of membrane are interconnected and uniform and their microstructure evolution can be controlled by adjusting the sintering temperature in a wide range. Kinetics analysis of the sintering behavior shows that the superior thermostability of spheres can eliminate the rapid uneven shrinkage of membrane and result in the uniform microstructures. In addition, it is found that the mass transfer among spheres with polycrystalline phases of θ and δ cannot occur unless these metastable phases transform to stable α-Al2O3, which is favorable to sinter at the same temperature range with the interlayer. Moreover, the effect of phase composition on mass transfer is further put forward. Finally, solid/water mixture has been processed by the synthesized membrane and the excellent filter performance confirms the uniform pores. [ABSTRACT FROM AUTHOR]

PbTe-based thermoelectric materials are good candidates for harvesting waste heat at mid-range temperatures due to their high thermoelectric efficiencies. Excellent quality and reliability of the bonding between the thermoelectric material and the electrode at high temperatures are essential for manufacturing thermoelectric generators. Here, a technique has been developed to achieve high-quality bonding between PbTe and the electrode. We have successfully performed one-step sintering of nickel electrode to n- type PbTe powder using spark plasma sintering. The fabricated interphase, composed of nickel telluride, is continuous and homogeneous across the junction, without visible flaws on the electrode or in the interphase and PbTe. To evaluate the long-term thermal stability of the fabricated bond, an aging test was conducted at 823 K for 360 h under vacuum. The microstructures and chemical composition of the fabricated bonding and the aged sample were investigated in detail by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy analysis. No excess reaction was observed between the electrode and the thermoelectric material after aging, supporting the formation of a chemically stable interphase, which acts as a diffusion barrier. Degradation of the PbTe was detected after aging, however. The fabricated interface meets the required criteria for maximum efficiency of PbTe materials. [ABSTRACT FROM AUTHOR]

Anatase TiO 2 film with 3D network nanoporous structure consisted of 1D nanowires is obtained on SnO 2 :F (FTO) glass substrate by in-situ hydrothermal synthesis and applied in mesoporous perovskite (CH 3 NH 3 PbI 3 ) solar cell. A thin Ti film is deposited on FTO substrate by magnetron sputtering before the hydrothermal treatment with sodium hydroxide solution. Then, a layer of network nanoporous TiO 2 (NT) film is formed. The efficiency of perovskite solar cell based on this 3D structure with one-step sintering can be optimized to 9.19%. The NT film consisted of 1D TiO 2 nanowires is beneficial to the transmission of charge carriers and the infiltration of hole transport material. And this one-step sintering process can reduce the interface defects and enhance the fill factor of the device. Then, we further optimize the surface of NT layer through TiCl 4 post-treatment. The post-treatment can optimize the carrier separation and the deposition of perovskite layer, thus improving the open-circuit voltage (V oc ) and short-circuit current density (J sc ) of perovskite solar cell. As a result, the value of J sc gets an enhancement of 45.63% and the efficiency of perovskite solar cell reaches up to 12.78%. [ABSTRACT FROM AUTHOR]

• The porous Ti-Cu alloy catalyst was synthesized by the one-step sintering method. • The introduction of Mo metal significantly improves the HER performance. • The first-principles approach gives the experiment a detailed interpretation of the atomic orbital hierarchy. In this paper, Ti-Cu porous alloy electrocatalysts were synthesized by simple mechanical alloying combined with a one-step sintering method, and the positive effects of milling time, sintering temperature, and sintering time on HER were explored. The results show that the Ti 2 Cu 3 porous alloy catalyst after ball milling has excellent electrocatalytic activity. After the introduction of transition metal Mo, the overpotential of ball-milled Mo-Ti 2 Cu 3 -600 electrocatalyst is 133 mV, and the corresponding Tafel slope is 97.37 mV·dec−1, second only to commercial Pt/C catalyst. At the same time, the first principle was used to reveal the interaction of electrons in catalysis. The effective mass of the ternary alloy containing Mo is 0.19 m 0 , and the original alloy catalyst is 0.28 m 0. It can be found that the introduction of Mo atoms improves the carrier migration efficiency, which has a high promotion effect on the catalytic performance of the original alloy. The reaction energy barrier is also reduced from 0.584 eV to 0.051 eV, which greatly improves the reaction process. Such a simple one-step sintering method can also obtain excellent electrocatalysts, which provides a new design idea for short-process processing of excellent electrocatalysts and has broad application prospects. [ABSTRACT FROM AUTHOR]

To explore a more efficient process parameter for controlling the microstructure and magnetic properties of liquid -phase assisted one-step sintering method, the effects of isolation medium size and uniformity on L 1 0 -FePtCu NPs have been studied. The grain size (d) of L 1 0 -FePtCu NPs has been refined by decreasing the average size of solid isolation mediums (D), and the relationship can be approximated as d = 6.60 × D 1/3 − 9.14. The disorder-order transition of the L 1 0 phase has been inhibited by decreasing the medium size, however, it has been facilitated by increasing the medium size uniformity. The ordering degree, coercive force, and magnetic energy product of L 1 0 -FePtCu NPs reach the highest when using the middle sized and best uniformity NaCl mediums (about 8 µm). This research indicates that controlling the interface between the solid isolation mediums and the precursors is an effective strategy to tune the microstructure and magnetic properties of one-step sintered highly ordered L 1 0 phase NPs. • L 10-FePtCu NPs with higher order degree and smaller size was successfully obtained. • A positive correlation between sizes of mediums and NPs was provided. • Mediums uniformity promoted the disorder-order transition of L 10-phase NPs. • Magnetic property of NPs was optimized by the size and uniformity of mediums [ABSTRACT FROM AUTHOR]

Copyright of Ceramica is the property of Associacao Brasileira de Ceramica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Ce0.8Gd0.05Y0.15O1.9 (GYDC) electrolyte was prepared by a carbonate co-precipitation method. Lithium nitrate at 1, 1.5, 2 and 3mol% was added to GYDC as sintering additive. 96% relative density was achieved for GYDC at sintering temperature of 800°C with addition of 1.5mol% LiNO3. The conductivities of GYDC with sintering aids LiNO3 were measured by a.c. impedance spectroscopy and showed comparable values to that of pure GYDC sample sintered at 1400°C. A single cell with 1.5mol% LiNO3 infiltrated GYDC electrolyte was fabricated by sintering at 800°C for only 2h. Lithiated NiO was synthesized by the glycine-nitrate combustion method and employed as cathode material. The cell was tested at temperatures from 500 to 575°C and a maximum power density of 73mWcm−2 was obtained at 575°C. These preliminary results indicate that LiNO3 is a very effective sintering additive for intermediate temperature solid oxide fuel cell fabrication. [Copyright &y& Elsevier]

A perovskite solar cell with a thin TiO2 compact film prepared by thermal oxidation of sputtered Ti film achieved a high efficiency of 15.07%. The thin TiO2 film prepared by thermal oxidation is very dense and inhibits the recombination process at the interface. The optimum thickness of the TiO2 compact film prepared by thermal oxidation is thinner than that prepared by spin-coating method. Also, the TiO2 compact film and the TiO2 porous film can be sintered at the same time. This one-step sintering process leads to a lower dark current density, a lower series resistance, and a higher recombination resistance than those of two-step sintering. Therefore, the perovskite solar cell with the TiO2 compact film prepared by thermal oxidation has a higher short-circuit current density and a higher fill factor.