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Showing papers on "Ceramic published in 2018"


Journal ArticleDOI
TL;DR: In this article, composites consisting of polyethylene-oxide/garnet electrolytes were fabricated for a safe solid-state Li-metal rechargeable battery, which achieved high discharge capacity (139.1% after 100 cycles) and high capacity retention (103.6% with coulombic efficiency of 100% after 50 cycles).

916 citations


Journal ArticleDOI
01 Nov 2018-Nature
TL;DR: It is shown that oxygen can take the form of ordered oxygen complexes, a state in between oxide particles and frequently occurring random interstitials, which lead to unprecedented enhancement in both strength and ductility in compositionally complex solid solutions, the so-called high-entropy alloys (HEAs).
Abstract: Oxygen, one of the most abundant elements on Earth, often forms an undesired interstitial impurity or ceramic phase (such as an oxide particle) in metallic materials. Even when it adds strength, oxygen doping renders metals brittle1–3. Here we show that oxygen can take the form of ordered oxygen complexes, a state in between oxide particles and frequently occurring random interstitials. Unlike traditional interstitial strengthening4,5, such ordered interstitial complexes lead to unprecedented enhancement in both strength and ductility in compositionally complex solid solutions, the so-called high-entropy alloys (HEAs)6–10. The tensile strength is enhanced (by 48.5 ± 1.8 per cent) and ductility is substantially improved (by 95.2 ± 8.1 per cent) when doping a model TiZrHfNb HEA with 2.0 atomic per cent oxygen, thus breaking the long-standing strength–ductility trade-off11. The oxygen complexes are ordered nanoscale regions within the HEA characterized by (O, Zr, Ti)-rich atomic complexes whose formation is promoted by the existence of chemical short-range ordering among some of the substitutional matrix elements in the HEAs. Carbon has been reported to improve strength and ductility simultaneously in face-centred cubic HEAs12, by lowering the stacking fault energy and increasing the lattice friction stress. By contrast, the ordered interstitial complexes described here change the dislocation shear mode from planar slip to wavy slip, and promote double cross-slip and thus dislocation multiplication through the formation of Frank–Read sources (a mechanism explaining the generation of multiple dislocations) during deformation. This ordered interstitial complex-mediated strain-hardening mechanism should be particularly useful in Ti-, Zr- and Hf-containing alloys, in which interstitial elements are highly undesirable owing to their embrittlement effects, and in alloys where tuning the stacking fault energy and exploiting athermal transformations13 do not lead to property enhancement. These results provide insight into the role of interstitial solid solutions and associated ordering strengthening mechanisms in metallic materials. Ordered oxygen complexes in high-entropy alloys enhance both strength and ductility in these compositionally complex solid solutions.

874 citations


Journal ArticleDOI
TL;DR: This research provides a new paradigm for designing material properties through engineering local structural heterogeneity, expected to benefit a wide range of functional materials.
Abstract: Piezoelectric materials, which respond mechanically to applied electric field and vice versa, are essential for electromechanical transducers. Previous theoretical analyses have shown that high piezoelectricity in perovskite oxides is associated with a flat thermodynamic energy landscape connecting two or more ferroelectric phases. Here, guided by phenomenological theories and phase-field simulations, we propose an alternative design strategy to commonly used morphotropic phase boundaries to further flatten the energy landscape, by judiciously introducing local structural heterogeneity to manipulate interfacial energies (that is, extra interaction energies, such as electrostatic and elastic energies associated with the interfaces). To validate this, we synthesize rare-earth-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT), as rare-earth dopants tend to change the local structure of Pb-based perovskite ferroelectrics. We achieve ultrahigh piezoelectric coefficients d33 of up to 1,500 pC N-1 and dielectric permittivity e33/e0 above 13,000 in a Sm-doped PMN-PT ceramic with a Curie temperature of 89 °C. Our research provides a new paradigm for designing material properties through engineering local structural heterogeneity, expected to benefit a wide range of functional materials.

756 citations



Book
10 May 2018
TL;DR: In this article, the authors present an overview of the history of Ceramics applications in engineering with ceramics, including powder processing, shape-forming, and final machining.
Abstract: Preface Introduction CERAMICS AS ENGINEERING MATERIALS What is a Ceramic? History of Ceramics Applications: Engineering with Ceramics STRUCTURE AND PROPERTIES Atomic Bonding and Crystal Structure Crystal Chemistry and Specific Crystal Structures Phase Equilibria and Phase Equilibrium Diagrams Physical and Thermal Behavior Mechanical Behavior and Measurement Time, Temperature, and Environmental Effects on Properties Electrical Behavior Dielectric, Magnetic, and Optical Behavior PROCESSING OF CERAMICS Powder Processing Shape-forming Processes Densification Final Machining Quality Assurance DESIGN WITH CERAMICS Design Considerations Design Approaches Failure Analysis Toughening of Ceramics Appendix A: Glossary Appendix B: Effective Ionic Radii for Cations and Anions Appendix C: Periodic Table Index

459 citations


Journal ArticleDOI
TL;DR: The newly developed capacitor exhibits a wide temperature usage range of -60 to 120 °C, with an energy-density variation of less than 10%, and satisfactory cycling reliability, with degradation of more than 8% over 106 cycles demonstrate that the NBT-0.45SBT multilayer ceramic is a promising candidate for high-power energy storage applications.
Abstract: The utilization of antiferroelectric (AFE) materials is thought to be an effective approach to enhance the energy density of dielectric capacitors. However, the high energy dissipation and inferior reliability that are associated with the antiferroelectric-ferroelectric phase transition are the main issues that restrict the applications of antiferroelectric ceramics. Here, simultaneously achieving high energy density and efficiency in a dielectric ceramic is proposed by combining antiferroelectric and relaxor features. Based on this concept, a lead-free dielectric (Na0.5 Bi0.5 )TiO3 -x(Sr0.7 Bi0.2 )TiO3 (NBT-xSBT) system is investigated and the corresponding multilayer ceramic capacitors (MLCCs) are fabricated. A record-high energy density of 9.5 J cm-3 , together with a high energy efficiency of 92%, is achieved in NBT-0.45SBT multilayer ceramic capacitors, which consist of ten dielectric layers with the single-layer thickness of 20 µm and the internal electrode area of 6.25 mm2 . Furthermore, the newly developed capacitor exhibits a wide temperature usage range of -60 to 120 °C, with an energy-density variation of less than 10%, and satisfactory cycling reliability, with degradation of less than 8% over 106 cycles. These characteristics demonstrate that the NBT-0.45SBT multilayer ceramic is a promising candidate for high-power energy storage applications.

458 citations


Journal ArticleDOI
TL;DR: It was found that the lattice parameter mismatch of the component monocarbides is a key factor for predicting single phase solid solution formation, revealing a vast new compositional space for the exploration of new UHTCs.
Abstract: Bulk equiatomic (Hf-Ta-Zr-Ti)C and (Hf-Ta-Zr-Nb)C high entropy Ultra-High Temperature Ceramic (UHTC) carbide compositions were fabricated by ball milling and Spark Plasma Sintering (SPS). It was found that the lattice parameter mismatch of the component monocarbides is a key factor for predicting single phase solid solution formation. The processing route was further optimised for the (Hf-Ta-Zr-Nb)C composition to produce a high purity, single phase, homogeneous, bulk high entropy material (99% density); revealing a vast new compositional space for the exploration of new UHTCs. One sample was observed to chemically decompose; indicating the presence of a miscibility gap. While this suggests the system is not thermodynamically stable to room temperature, it does reveal further potential for the development of new in situ formed UHTC nanocomposites. The optimised material was subjected to nanoindentation testing and directly compared to the constituent mono/binary carbides, revealing a significantly enhanced hardness (36.1 ± 1.6 GPa,) compared to the hardest monocarbide (HfC, 31.5 ± 1.3 GPa) and the binary (Hf-Ta)C (32.9 ± 1.8 GPa).

440 citations


Journal ArticleDOI
TL;DR: In this paper, a simple chemical vapor deposition (CVD) route for the direct growth of edge-rich graphene (ERG) with tailored structures and tunable dielectric properties in porous Si3N4 ceramics using only methyl alcohol (CH3OH) as precursor is reported.
Abstract: High-performance graphene microwave absorption materials are highly desirable in daily life and some extreme situations. A simple technique for the direct growth of graphene as absorption fillers in wave-transmitting matrices is of paramount importance to bring it to real-world application. Herein, a simple chemical vapor deposition (CVD) route for the direct growth of edge-rich graphene (ERG) with tailored structures and tunable dielectric properties in porous Si3N4 ceramics using only methyl alcohol (CH3OH) as precursor is reported. The large O/C atomic ratio of CH3OH helps to build a mild oxidizing atmosphere and leads to a unique structure featuring open graphite nanosteps and freestanding nanoplanes, endowing the ERG/Si3N4 hybrid with an appropriate balance between good impedance matching and strong loss capacity. Accordingly, the prepared materials exhibit superior electromagnetic wave absorption, far surpassing that of traditional CVD graphene and reduced graphene oxide-based materials, achieving an effective absorption bandwidth of 4.2 GHz covering the entire X band, with a thickness of 3.75 mm and a negligibly low loading content of absorbents. The results provide new insights for developing novel microwave absorption materials with strong reflection loss and wide absorption frequency range.

417 citations


Journal ArticleDOI
TL;DR: In this article, a novel BaTiO3-based lead-free composition with an ultrahigh energy storage density (2.41 J cm−3) and a high energy storage efficiency of 91.6% was reported.
Abstract: The development of energy storage devices with a high energy storage density, high power density, and excellent stability has always been a long-cherished goal for many researchers as they tackle issues concerning energy conservation and environmental protection. In this work, we report a novel BaTiO3-based lead-free composition (0.85BaTiO3–0.15Bi(Zn1/2Sn1/2)O3) with an ultrahigh energy storage density (2.41 J cm−3) and a high energy storage efficiency of 91.6%, which is superior to other lead-free systems reported recently. The energy storage properties of 0.85BT–0.15BZS ceramic manifest excellent frequency stability (5–1000 Hz) and fatigue endurance (cycle number: 105). The pulsed charging–discharging process is measured to elucidate the actual operation performance in the 0.85BT–0.15BZS ceramic. Delightfully, the 0.85BT–0.15BZS ceramic also possesses an ultrahigh current density of 551 A cm−2 and a giant power density of 30.3 MW cm−3, and the stored energy is released in sub-microseconds. Moreover, the 0.85BT–0.15BZS ceramic exhibits outstanding temperature stability of its dielectric properties, energy storage properties, and charging–discharging performance over a broad temperature range (20–160 °C) due to the weakly-coupled relaxor behavior. These results not only indicate the superior potential of environment-friendly BaTiO3-based relaxor ferroelectric ceramics for the design of ceramic capacitors of both high energy storage and power applications, but they also show the merit of the weakly-coupled relaxor behavior to improve the thermal stability of energy storage properties.

384 citations


Journal ArticleDOI
TL;DR: In this review the different types of MEAM techniques and relevant industrial approaches for the fabrication of metallic and ceramic components are described and a comparison of the parts produced via MEAM-HP with those produced via other manufacturing techniques is presented.
Abstract: Additive manufacturing (AM) is the fabrication of real three-dimensional objects from metals, ceramics, or plastics by adding material, usually as layers. There are several variants of AM; among them material extrusion (ME) is one of the most versatile and widely used. In MEAM, molten or viscous materials are pushed through an orifice and are selectively deposited as strands to form stacked layers and subsequently a three-dimensional object. The commonly used materials for MEAM are thermoplastic polymers and particulate composites; however, recently innovative formulations of highly-filled polymers (HP) with metals or ceramics have also been made available. MEAM with HP is an indirect process, which uses sacrificial polymeric binders to shape metallic and ceramic components. After removing the binder, the powder particles are fused together in a conventional sintering step. In this review the different types of MEAM techniques and relevant industrial approaches for the fabrication of metallic and ceramic components are described. The composition of certain HP binder systems and powders are presented; the methods of compounding and filament making HP are explained; the stages of shaping, debinding, and sintering are discussed; and finally a comparison of the parts produced via MEAM-HP with those produced via other manufacturing techniques is presented.

357 citations


Journal ArticleDOI
Yang Si1, Xueqin Wang1, Lvye Dou1, Jianyong Yu1, Bin Ding1 
TL;DR: This approach causes the random-deposited SiO2 nanofibers to assemble into elastic ceramic aerogels with tunable densities and desired shapes on a large scale, and the resulting CNFAs exhibit the integrated properties of flyweight densities of >0.15 mg cm−3, rapid recovery from 80% strain, zero Poisson’s ratio, and temperature-invariant superelasticity to 1100°C.
Abstract: Ultralight aerogels that are both highly resilient and compressible have been fabricated from various materials including polymer, carbon, and metal. However, it has remained a great challenge to realize high elasticity in aerogels solely based on ceramic components. We report a scalable strategy to create superelastic lamellar-structured ceramic nanofibrous aerogels (CNFAs) by combining SiO2 nanofibers with aluminoborosilicate matrices. This approach causes the random-deposited SiO2 nanofibers to assemble into elastic ceramic aerogels with tunable densities and desired shapes on a large scale. The resulting CNFAs exhibit the integrated properties of flyweight densities of >0.15 mg cm-3, rapid recovery from 80% strain, zero Poisson's ratio, and temperature-invariant superelasticity to 1100°C. The integral ceramic nature also provided the CNFAs with robust fire resistance and thermal insulation performance. The successful synthesis of these fascinating materials may provide new insights into the development of ceramics in a lightweight, resilient, and structurally adaptive form.

Journal ArticleDOI
TL;DR: In this article, a novel high-entropy carbide ceramic, (Hf0.2Zr 0.2Ta 0.3Nb0.5Ti 0.4Nb1.2Ti0.4Ti 0.2Nb 0.5Nb 1.2C, with a single phase rock salt structure was synthesized by spark plasma sintering.
Abstract: A novel high‐entropy carbide ceramic, (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C, with a single‐phase rock salt structure, was synthesized by spark plasma sintering. X‐ray diffraction confirmed the formation of a single‐phase rock salt structure at 26‐1140°C in Argon atmosphere, in which the 5 metal elements may share a cation position while the C element occupies the anion position. (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C exhibits a much lower thermal diffusivity and conductivity than the binary carbides HfC, ZrC, TaC, and TiC, which may result from the significant phonon scattering at its distorted anion sublattice. (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C inherits the high elastic modulus and hardness of the binary carbide ceramics.

Journal ArticleDOI
TL;DR: In this paper, a novel polymer/ceramic nanocomposite is fabricated using core-shell BaTiO3@SiO2 (BT@SO) structures with a diameter less than 10

Journal ArticleDOI
TL;DR: This study examines the compositional dependence of the three determining factors for ionic conductivity, including ion mobility, ion transport pathways, and active ion concentration and finds that a higher content of LLZO leads to improved electrochemical stability of composite electrolytes.
Abstract: Composite electrolytes are widely studied for their potential in realizing improved ionic conductivity and electrochemical stability. Understanding the complex mechanisms of ion transport within composites is critical for effectively designing high-performance solid electrolytes. This study examines the compositional dependence of the three determining factors for ionic conductivity, including ion mobility, ion transport pathways, and active ion concentration. The results show that with increase in the fraction of ceramic Li7La3Zr2O12 (LLZO) phase in the LLZO–poly(ethylene oxide) composites, ion mobility decreases, ion transport pathways transit from polymer to ceramic routes, and the active ion concentration increases. These changes in ion mobility, transport pathways, and concentration collectively explain the observed trend of ionic conductivity in composite electrolytes. Liquid additives alter ion transport pathways and increase ion mobility, thus enhancing ionic conductivity significantly. It is also...

Journal ArticleDOI
TL;DR: A three-dimensional fiber-network-reinforced bicontinuous solid composite electrolyte with flexible Li+-conductive network (lithium aluminum titanium phosphate (LATP)/polyacrylonitrile) helps to enhance electrochemical stability on the electrode/electrolyte interface by isolating Li and LATP and suppress Li dendrites growth by mechanical reinforcement of fiber network for the composite solid electrolyte.
Abstract: Replacement of flammable organic liquid electrolytes with solid Li+ conductors is a promising approach to realize excellent performance of Li metal batteries. However, ceramic electrolytes are either easily reduced by Li metal or penetrated by Li dendrites through their grain boundaries, and polymer electrolytes are also faced with instability on the electrode/electrolyte interface and weak mechanical property. Here, we report a three-dimensional fiber-network-reinforced bicontinuous solid composite electrolyte with flexible Li+-conductive network (lithium aluminum titanium phosphate (LATP)/polyacrylonitrile), which helps to enhance electrochemical stability on the electrode/electrolyte interface by isolating Li and LATP and suppress Li dendrites growth by mechanical reinforcement of fiber network for the composite solid electrolyte. The composite electrolyte shows an excellent electrochemical stability after 15 days of contact with Li metal and has an enlarged tensile strength (10.72 MPa) compared to the...

Journal ArticleDOI
TL;DR: Measuring the structural, mechanical, and thermal properties of single-crystal entropy-stabilized oxides, it is shown that local ionic charge disorder can effectively reduce thermal conductivity without compromising mechanical stiffness, resulting in this class of material possessing the highest ratio of elastic modulus to thermal Conductivity of any isotropic crystal.
Abstract: Manipulating a crystalline material's configurational entropy through the introduction of unique atomic species can produce novel materials with desirable mechanical and electrical properties. From a thermal transport perspective, large differences between elemental properties such as mass and interatomic force can reduce the rate at which phonons carry heat and thus reduce the thermal conductivity. Recent advances in materials synthesis are enabling the fabrication of entropy-stabilized ceramics, opening the door for understanding the implications of extreme disorder on thermal transport. Measuring the structural, mechanical, and thermal properties of single-crystal entropy-stabilized oxides, it is shown that local ionic charge disorder can effectively reduce thermal conductivity without compromising mechanical stiffness. These materials demonstrate similar thermal conductivities to their amorphous counterparts, in agreement with the theoretical minimum limit, resulting in this class of material possessing the highest ratio of elastic modulus to thermal conductivity of any isotropic crystal.

Journal ArticleDOI
TL;DR: In this article, a single-phase perovskite Srx(Bi1−xNa0.97−xLi0.03)0.5TiO3 (x = 0.30 and 0.38) bulk ceramics, prepared using solid-state reaction method, were carefully studied for the dielectric capacitor application.

Journal ArticleDOI
07 Mar 2018-ACS Nano
TL;DR: The fabrication and properties of a highly porous three-dimensional SiC NWA assembled by a large number of interweaving 3C-SiC nanowires of 20-50 nm diameter and tens to hundreds of micrometers in length are reported.
Abstract: Ultralight ceramic aerogels with the property combination of recoverable compressibility and excellent high-temperature stability are attractive for use in harsh environments. However, conventional ceramic aerogels are usually constructed by oxide ceramic nanoparticles, and their practical applications have always been limited by the brittle nature of ceramics and volume shrinkage at high temperature. Silicon carbide (SiC) nanowire offers the integrated properties of elasticity and flexibility of one-dimensional (1D) nanomaterials and superior high-temperature thermal and chemical stability of SiC ceramics, which makes it a promising building block for compressible ceramic nanowire aerogels (NWAs). Here, we report the fabrication and properties of a highly porous three-dimensional (3D) SiC NWA assembled by a large number of interweaving 3C-SiC nanowires of 20–50 nm diameter and tens to hundreds of micrometers in length. The SiC NWA possesses ultralow density (∼5 mg cm–3), excellent mechanical properties o...

Journal ArticleDOI
TL;DR: A polyethylene oxide (PEO)-based composite solid polymer electrolyte filled with one-dimensional (1D) ceramic Li033La0557TiO3 (LLTO) nanofibers was designed and prepared as discussed by the authors.
Abstract: A polyethylene oxide (PEO)-based composite solid polymer electrolyte filled with one-dimensional (1D) ceramic Li033La0557TiO3 (LLTO) nanofibers was designed and prepared It exhibits a high ionic conductivity of 24 × 10−4 S cm−1 at room temperature and a large electrochemical stability window of up to 50 V vs Li/Li+, and is a promising electrolyte candidate for all solid-state lithium batteries

Journal ArticleDOI
TL;DR: In this article, a lead-free NaNbO3-based lead free ceramic capacitance with fast charge-discharge performance and excellent energy storage characteristics has been proposed.
Abstract: Recently, ceramic capacitors with fast charge–discharge performance and excellent energy storage characteristics have received considerable attention. Novel NaNbO3-based lead-free ceramics (0.80NaN...

Journal ArticleDOI
TL;DR: The vertically aligned interfacial structure in the composite electrolytes enables the viable application of the composite solid electrolyte with superior ionic conductivity and high hardness, allowing Li-Li cells to be cycled at a small polarization without Li dendrite penetration.
Abstract: Among all solid electrolytes, composite solid polymer electrolytes, comprised of polymer matrix and ceramic fillers, garner great interest due to the enhancement of ionic conductivity and mechanical properties derived from ceramic–polymer interactions. Here, we report a composite electrolyte with densely packed, vertically aligned, and continuous nanoscale ceramic–polymer interfaces, using surface-modified anodized aluminum oxide as the ceramic scaffold and poly(ethylene oxide) as the polymer matrix. The fast Li+ transport along the ceramic–polymer interfaces was proven experimentally for the first time, and an interfacial ionic conductivity higher than 10–3 S/cm at 0 °C was predicted. The presented composite solid electrolyte achieved an ionic conductivity as high as 5.82 × 10–4 S/cm at the electrode level. The vertically aligned interfacial structure in the composite electrolytes enables the viable application of the composite solid electrolyte with superior ionic conductivity and high hardness, allowin...

Journal ArticleDOI
TL;DR: In this paper, a 3D ordered bicontinuous conducting ceramic and insulating polymer microchannels were used to construct 3D scaffolds with 3D printed polymer template.
Abstract: Hybrid solid electrolytes, composed of 3D ordered bicontinuous conducting ceramic and insulating polymer microchannels are reported. The ceramic channels provide continuous, uninterrupted pathways, maintaining high ionic conductivity between the electrodes, while the polymer channels permit improvement of the mechanical properties from that of the ceramic alone, in particular mitigation of the ceramic brittleness. The conductivity of a ceramic electrolyte is usually limited by resistance at the grain boundaries, necessitating dense ceramics. The conductivity of the 3D ordered hybrid is reduced by only the volume fraction occupied by the ceramic, demonstrating that the ceramic channels can be sintered to high density similar to a dense ceramic disk. The hybrid electrolytes are demonstrated using the ceramic lithium ion conductor Li1.4Al0.4Ge1.6(PO4)3 (LAGP). Structured LAGP 3D scaffolds with empty channels were prepared by negative replication of a 3D printed polymer template. Filling the empty channels with non-conducting polypropylene (PP) or epoxy polymer (epoxy) creates the structured hybrid electrolytes with 3D bicontinuous ceramic and polymer microchannels. Printed templating permits precise control of the ceramic to polymer ratio and the microarchitecture; as demonstrated by the formation of cubic, gyroidal, diamond and spinodal (bijel) structures. The electrical and mechanical properties depend on the microarchitecture, the gyroid filled with epoxy giving the best combination of conductivity and mechanical properties. An ionic conductivity of 1.6 × 10−4 S cm−1 at room temperature was obtained, reduced from the conductivity of a sintered LAGP pellet only by the volume fraction occupied by the ceramic. The mechanical properties of the gyroid LAGP–epoxy electrolyte demonstrate up to 28% higher compressive failure strain and up to five times the flexural failure strain of a LAGP pellet before rupture. Notably, this demonstrates that ordered ceramic and polymer hybrid electrolytes can have superior mechanical properties without significantly compromising ionic conductivity, which addresses one of the key challenges for all-solid-state batteries.

Journal ArticleDOI
TL;DR: Inorganic α-Ag2S semiconductor, which has preferential slip planes in the crystal structure and irregularly distributed bonds of silver atoms preventing cleavage, demonstrates metal-like ductility at room temperature.
Abstract: Ductility is common in metals and metal-based alloys, but is rarely observed in inorganic semiconductors and ceramic insulators. In particular, room-temperature ductile inorganic semiconductors were not known until now. Here, we report an inorganic α-Ag2S semiconductor that exhibits extraordinary metal-like ductility with high plastic deformation strains at room temperature. Analysis of the chemical bonding reveals systems of planes with relatively weak atomic interactions in the crystal structure. In combination with irregularly distributed silver–silver and sulfur–silver bonds due to the silver diffusion, they suppress the cleavage of the material, and thus result in unprecedented ductility. This work opens up the possibility of searching for ductile inorganic semiconductors/ceramics for flexible electronic devices.

Journal ArticleDOI
TL;DR: In this paper, a stereolithography-based method of 3D printing was successfully used to fabricate a complex-shaped triangular zirconia cutting tool with a tool withdrawal groove and a honeycomb component.

Journal ArticleDOI
TL;DR: This work synthesized composite polymer electrolytes (CPEs) with a three-dimensional (3D) Li0.33La0.557TiO3 network as a nano-backbone in poly(ethylene oxide) matrix by hot-pressing and quenching and obtained self-standing 3D-CPE membranes that could suppress the growth of Li dendrite and reduce polarization.
Abstract: Solid electrolytes with high ionic conductivity and good mechanical properties are required for solid-state lithium-ion batteries. In this work, we synthesized composite polymer electrolytes (CPEs) with a three-dimensional (3D) Li0.33La0.557TiO3 (LLTO) network as a nano-backbone in poly(ethylene oxide) matrix by hot-pressing and quenching. Self-standing 3D-CPE membranes were obtained with the support of the LLTO nano-backbone. These membranes had much better thermal stability and enhanced mechanical strength in comparison with solid polymer electrolytes. The influence of lithium (Li) salt concentration on the conductivity of 3D-CPEs was systematically studied, and an ionic conductivity as high as 1.8 × 10–4 S·cm–1 was achieved at room temperature. The electrochemical window of the 3D-CPEs was 4.5 V vs Li/Li+. More importantly, the 3D-CPE membranes could suppress the growth of Li dendrite and reduce polarization; therefore, a symmetric Li|3D-CPE|Li cell with these membranes was cycled at a current density ...

Journal ArticleDOI
TL;DR: In this article, the authors presented a physically thin, structurally dense and chemically homogeneous electrolyte, BaCe0.55Zr0.15O3-δ (BCZY3), through a facile anode-assisted densification of the electrolyte on a structurally and compositionally uniform anode support.
Abstract: In spite of various advantages of protonic ceramic fuel cells over conventional fuel cells, distinct scepticism currently remains about their applicability because of lower-than-predicted performance and difficulty with scale-up. These challenges mainly stem from the refractory nature of proton-conducting ceramic electrolytes and the low chemical stability of these materials during the sintering process. Here, we present the fabrication of a physically thin, structurally dense and chemically homogeneous electrolyte, BaCe0.55Zr0.3Y0.15O3-δ (BCZY3), through a facile anode-assisted densification of the electrolyte on a structurally and compositionally uniform anode support, which resulted in breakthroughs in performance and scalability. A BCZY3-based protonic ceramic fuel cell with a size of 5 × 5 cm2 exhibits an area-specific ohmic resistance of 0.09 Ω cm2 and delivers a power as high as 20.8 W per single cell at 600 °C. Protonic ceramic fuel cells (PCFCs) operate at lower temperatures than solid oxide fuel cells but suffer from lower performances, especially during scale-up. Here, the authors report a 25 cm2 PCFC based on a BaCe0.55Zr0.3Y0.15O3–δ electrolyte that displays a record-high power density of 20.8 W at 600 °C.

Journal ArticleDOI
TL;DR: A summary of the recent progress on the fabrication of single and multi-ceramic structures by robocasting is provided, as well as the prospects of achieving shapeable ceramic structures.
Abstract: Additive manufacturing (AM) of ceramic materials has attracted tremendous attention in recent years, due to its potential to fabricate suitable advanced ceramic structures for various engineering applications. Robocasting, a subset of ceramic AM, is an ideal technique for constructing fine and dense ceramic structures with geometrically complex morphology. With the freedom and convenience to deposit various materials within any 3D spatial position, ceramic robocasting opens up unlimited opportunities, which are otherwise hardly attainable from other AM techniques. Here, a summary of the recent progress on the fabrication of single and multi-ceramic structures by robocasting is provided, as well as the prospects of achieving shapeable ceramic structures. The current challenges in ceramic robocasting and an outlook on its development, especially toward the fabrication of self-shaping ceramic structures, are also discussed.

BookDOI
18 May 2018
TL;DR: The Chemical Synthesis of Ceramic Powders: An Overview, by Elis CarlstrOm The chemical synthesis of ceramic powders, by Richard Riman Surface Chemical Characterization of CPDP, by Lennart BergstOm Dispersion and Stability of CDPs in Liquids, by Robert Pugh Rheology of Concentrated Suspensions, by EisCarlstrOmm Surface Chemistry in Dry Pressing and Surface and Colloid Chemistry in Ceramic Casting Operations, by Michael Persson Injection Molding, by J. R. G
Abstract: "Surface and Colloid Chemistry in Ceramics: An Overview, by Elis CarlstrOm The Chemical Synthesis of Ceramic Powders, by Richard Riman Surface Chemical Characterization of Ceramic Powders, by Lennart BergstrOm Dispersion and Stability of Ceramic Particles in Liquids, by Robert Pugh Rheology of Concentrated Suspensions, by Lennart BergstOm Surface Chemistry in Dry Pressing, by Elis CarlstrOm Surface and Colloid Chemistry in Ceramic Casting Operations, by Michael Persson Injection Molding, by J. R. G. Evans "

Journal ArticleDOI
TL;DR: In this paper, a scalable ceramic-polymer composites based on three-dimensional interconnected piezoelectric microfoams is proposed. But the authors admit that the 3-D interconnected architecture presents a continuous pathway for load transfer to break the load-transfer scaling law seen in the conventional composites with low-dimensional ceramic fillers.
Abstract: Flexible piezoelectric materials are pivotal to a variety of emerging applications ranging from wearable electronic devices, sensors to biomedical devices. Current ceramic-polymer composites with embedded low-dimensional ceramic fillers, though mechanically flexible, suffer from low piezoelectricity owing to the poor load-transfer efficiency that typically scales with the stiffness ratio of the polymer matrix to the ceramic fillers. Herein we introduce the scalable ceramic-polymer composites based on three-dimensional (3-D) interconnected piezoelectric microfoams. Comprehensive mechanics analyses reveal that the 3-D interconnected architecture presents a continuous pathway for load transfer to break the load-transfer scaling law seen in the conventional composites with low-dimensional ceramic fillers. The 3-D composite exhibits exceptional piezoelectric characteristics under multiple loading conditions (i.e., compression, stretching, and bending) and high mechanical durability under thousands of cycles. The 3-D composite also displays excellent pyroelectricity, thereby enabling concurrent thermal and mechanical energy scavenging. Our findings suggest an innovative material framework for high-performance energy harvesters and self-powered micromechanical devices.

Journal ArticleDOI
21 Nov 2018-Joule
TL;DR: In this paper, the authors investigate the growth mechanisms and the tendency of the deposited metal to penetrate nanoporous ceramic separators across a range of practical current densities and suggest the existence of three growth modes of lithium, due to the competing reactions of lithium deposition and the solid electrolyte interphase formation.