Showing papers in "Annual Review of Materials Research in 2015"
TL;DR: In this paper, the authors provide a holistic overview of the different synthesis and characterization techniques, electronic and photonic device characteristics, and catalytic properties of transition metal dichalcogenides and their heterostructures, and comment on the challenges that need to be overcome for full-scale commercial implementation of this novel class of layered materials.
Abstract: Interest in 2D materials and van der Waals solids is growing exponentially across various scientific and engineering disciplines owing to their fascinating electrical, optical, chemical, and thermal properties. Whereas the micromechanical exfoliation technique has been adopted for rapid material characterization and demonstration of innovative device ideas based on these 2D systems, significant advances have recently been made in large-scale homogeneous and heterogeneous growth of these materials. This review reflects recent progress and outlines future prospects of these novel 2D materials. We provide a holistic overview of the different synthesis and characterization techniques, electronic and photonic device characteristics, and catalytic properties of transition metal dichalcogenides and their heterostructures. We also comment on the challenges that need to be overcome for full-scale commercial implementation of this novel class of layered materials.
551 citations
TL;DR: In this article, the authors reviewed recent progress made in the development of polymer dielectrics with high energy storage density, which can potentially lead to significant weight and volume reduction in polymer film capacitors.
Abstract: Polymer film capacitors are critical components in many high-power electrical systems. Because of the low energy density of conventional polymer dielectrics, these capacitors currently occupy significant volume in the entire electrical system. This article reviews recent progress made in the development of polymer dielectrics with high energy storage density, which can potentially lead to significant weight and volume reduction in polymer film capacitors. The increase in energy density is achieved through two approaches, namely (a) the development of novel polymers with high electric polarization and optimized dielectric responses and (b) the development of nanocomposites containing polymer matrixes with high breakdown strength and inorganic nanofillers with high polarization. Promising progress has been made through both strategies, resulting in a maximum energy density of >30 J/cm3, which is at least 5 times higher than those of conventional polymer dielectrics. The state-of-the-art manufacturing method...
467 citations
TL;DR: In this article, the authors provide a detailed account of these improvements, focusing specifically on microstructure evolution during processing, and expander expansion during the fabrication of dual-phase alloys.
Abstract: Dual-phase (DP) steel is the flagship of advanced high-strength steels, which were the first among various candidate alloy systems to find application in weight-reduced automotive components. On the one hand, this is a metallurgical success story: Lean alloying and simple thermomechanical treatment enable use of less material to accomplish more performance while complying with demanding environmental and economic constraints. On the other hand, the enormous literature on DP steels demonstrates the immense complexity of microstructure physics in multiphase alloys: Roughly 50 years after the first reports on ferrite-martensite steels, there are still various open scientific questions. Fortunately, the last decades witnessed enormous advances in the development of enabling experimental and simulation techniques, significantly improving the understanding of DP steels. This review provides a detailed account of these improvements, focusing specifically on (a) microstructure evolution during processing, (b) exp...
438 citations
TL;DR: In this paper, the synthesis, transfer, and characterization methods of graphene and 2D materials and their application to flexible devices as well as comparison with other competing materials are discussed. And a review of the application of graphene in flexible electronics is presented.
Abstract: Recently, 2D materials have been intensively studied as emerging materials for future electronics, including flexible electronics, photonics, and electrochemical energy storage devices. Among representative 2D materials (such as graphene, boron nitride, and transition metal dichalcogenides) that exhibit extraordinary properties, graphene stands out in the flexible electronics field due to its combination of high electron mobility, high thermal conductivity, high specific surface area, high optical transparency, excellent mechanical flexibility, and environmental stability. This review covers the synthesis, transfer, and characterization methods of graphene and 2D materials and graphene's application to flexible devices as well as comparison with other competing materials.
332 citations
TL;DR: In this article, the mechanisms of corrosion and hydrogen pickup and the role of alloy selection in minimizing both phenomena are considered on the basis of two principal characteristics: the pretransition kinetics and the loss of oxide protectiveness at transition.
Abstract: During operation, nuclear fuel rods are immersed in the primary water, causing waterside corrosion and consequent hydrogen ingress. In this review, the mechanisms of corrosion and hydrogen pickup and the role of alloy selection in minimizing both phenomena are considered on the basis of two principal characteristics: the pretransition kinetics and the loss of oxide protectiveness at transition. In zirconium alloys, very small changes in composition or microstructure can cause significant corrosion differences so that corrosion performance is strongly alloy dependent. The alloys show different, but reproducible, subparabolic pretransition kinetics and transition thicknesses. A mechanism for oxide growth and breakup based on a detailed study of the oxide structure can explain these results. Through the use of the recently developed coupled current charge compensation model of corrosion kinetics and hydrogen pickup, the subparabolic kinetics and the hydrogen fraction can be rationalized: Hydrogen pickup incr...
291 citations
TL;DR: A philosophy for defining what constitutes a virtual high-throughput screen is discussed, and the choices that influence decisions at each stage of the computational funnel are investigated, including an in-depth discussion of the generation of molecular libraries.
Abstract: A philosophy for defining what constitutes a virtual high-throughput screen is discussed, and the choices that influence decisions at each stage of the computational funnel are investigated, including an in-depth discussion of the generation of molecular libraries. Additionally, we provide advice on the storing, analysis, and visualization of data on the basis of extensive experience in our research group.
241 citations
TL;DR: In recent years, two important advances have opened new doors for the characterization and determination of magnetic structures as mentioned in this paper, and the subsequent development of a series of computer tools that allow a more efficient and comprehensive application of magnetic symmetry, both commensurate and incommensurate.
Abstract: In recent years, two important advances have opened new doors for the characterization and determination of magnetic structures. Firstly, researchers have produced computer-readable listings of the magnetic or Shubnikov space groups. Secondly, they have extended and applied the superspace formalism, which is presently the standard approach for the description of nonmagnetic incommensurate structures and their symmetry, to magnetic structures. These breakthroughs have been the basis for the subsequent development of a series of computer tools that allow a more efficient and comprehensive application of magnetic symmetry, both commensurate and incommensurate. Here we briefly review the capabilities of these computation instruments and present the fundamental concepts on which they are based, providing various examples. We show how these tools facilitate the use of symmetry arguments expressed as either a magnetic space group or a magnetic superspace group and allow the exploration of the possible magnetic o...
239 citations
TL;DR: In this article, one aspect of materials informatics is explored, namely how one can efficiently explore for new knowledge in regimes of structure-property space, especially when no reasonable selection pathways based on theory or clear choice are available.
Abstract: Materials informatics provides the foundations for a new paradigm of materials discovery. It shifts our emphasis from one of solely searching among large volumes of data that may be generated by experiment or computation to one of targeted materials discovery via high-throughput identification of the key factors (i.e., “genes”) and via showing how these factors can be quantitatively integrated by statistical learning methods into design rules (i.e., “gene sequencing”) governing targeted materials functionality. However, a critical challenge in discovering these materials genes is the difficulty in unraveling the complexity of the data associated with numerous factors including noise, uncertainty, and the complex diversity of data that one needs to consider (i.e., Big Data). In this article, we explore one aspect of materials informatics, namely how one can efficiently explore for new knowledge in regimes of structure-property space, especially when no reasonable selection pathways based on theory or clear...
227 citations
TL;DR: The concept of process-structure-property (PSP) linkages is introduced and illustrated how the determination of PSPs is one of the main objectives of materials data science.
Abstract: The field of materials science and engineering is on the cusp of a digital data revolution. After reviewing the nature of data science and Big Data, we discuss the features of materials data that distinguish them from data in other fields. We introduce the concept of process-structure-property (PSP) linkages and illustrate how the determination of PSPs is one of the main objectives of materials data science. Then we review a selection of materials databases, as well as important aspects of materials data management, such as storage hardware, archiving strategies, and data access strategies. We introduce the emerging field of materials data analytics, which focuses on data-driven approaches to extract and curate materials knowledge from available data sets. The critical need for materials e-collaboration platforms is highlighted, and we conclude the article with a number of suggestions regarding the near-term future of the materials data science field.
199 citations
TL;DR: In this paper, the phase stability, deformation, and oxidation properties of Co-base superalloys were discussed, and it was shown that adding Ta, Ti, Nb, Hf, and Ni are effective in simultaneously increasing phase stability and stacking fault energy of γ′-Co3(Al,W).
Abstract: The discovery of the γ′-Co3(Al,W) phase with an L12 structure provided Co-base alloys with a new strengthening mechanism, enabling a new class of high-temperature material: Co-base superalloys. This review discusses the current understanding of the phase stability, deformation, and oxidation behaviors of γ′ single-phase and γ + γ′ two-phase alloys in comparison with Ni-base γ′-L12 phase and γ + γ′ superalloys. Relatively low stacking fault energies and phase stability of the γ′ phase compared with those in Ni-base alloys are responsible for the unique deformation behaviors observed in Co-base γ′ and γ + γ′ alloys. Controlling energies of planar defects, such as stacking faults and antiphase boundaries, by alloying is critical for alloy development. Experimental and density functional theory studies indicate that additions of Ta, Ti, Nb, Hf, and Ni are effective in simultaneously increasing the phase stability and stacking fault energy of γ′-Co3(Al,W), thus improving the high-temperature strength of Co-bas...
185 citations
TL;DR: A review of recent developments in the rapidly emerging field of 2D nanoarchitectonics from a materials chemistry perspective, with a focus on the types of heterostructures available, their assembly strategies, and their emerging properties is presented in this article.
Abstract: Graphene's legacy has become an integral part of today's condensed matter science and has equipped a whole generation of scientists with an armory of concepts and techniques that open up new perspectives for the postgraphene area. In particular, the judicious combination of 2D building blocks into vertical heterostructures has recently been identified as a promising route to rationally engineer complex multilayer systems and artificial solids with intriguing properties. The present review highlights recent developments in the rapidly emerging field of 2D nanoarchitectonics from a materials chemistry perspective, with a focus on the types of heterostructures available, their assembly strategies, and their emerging properties. This overview is intended to bridge the gap between two major—yet largely disjunct—developments in 2D heterostructures, which are firmly rooted in solid-state chemistry or physics. Although the underlying types of heterostructures differ with respect to their dimensions, layer alignme...
TL;DR: Fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering are discussed.
Abstract: Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering.
TL;DR: In this paper, a review of electric-field control and modulation of various degrees of freedom through the medium of multiferroic BiFeO3 is presented, and an in-depth understanding of those electrically controlled phenomena and breakthroughs is highlighted, paving a new route toward multifunctional nanoelectronics.
Abstract: A promising approach to the next generation of low-power, functional, and green nanoelectronics relies on advances in the electric-field control of lattice, charge, orbital, and spin degrees of freedom in novel materials. The possibility of electric-field control of these multiple materials functionalities offers interesting options across a range of modern technologies, including information communication, computing processes, data storage, active components, and functional electronics. This article reviews electric-field control and modulation of various degrees of freedom through the medium of multiferroic BiFeO3. Coexisting order parameters and inherent couplings in this materials system form a potent playground, enabling direct and indirect manipulation to obtain intriguing properties and functionalities with an electric stimulus. An in-depth understanding of those electrically controlled phenomena and breakthroughs is highlighted, paving a new route toward multifunctional nanoelectronics. This artic...
TL;DR: In this paper, first-principles calculations based on density functional theory and related techniques enable the predictive modeling of the linear and nonlinear optical properties of materials without adjustable or empirical parameters.
Abstract: Modern first-principles calculations based on density functional theory and related techniques enable the predictive modeling of the linear and nonlinear optical properties of materials without adjustable or empirical parameters. Today, atomistic calculations are an indispensable tool by which to understand the interrelationship between the underlying structure and the measured optical properties and are particularly suited for the design of new materials with desirable optical responses and performance. In this article, we discuss the first-principles design methodology, and we review recent results from the literature that exemplify the predictive power of the method for numerous inorganic materials and nanostructures. We also discuss topics of active research and future opportunities that will enable the wider adoption of atomistic simulation techniques for predictive materials design.
TL;DR: The large hydration enthalpy of inorganic interlayer cations sandwiched between moderately negatively charged silicate layers endows to smectites (e.g., hectorite) remarkably rich intracrystalline reactivity compared with most other layered materials as discussed by the authors.
Abstract: The large hydration enthalpy of inorganic interlayer cations sandwiched between moderately negatively charged silicate layers endows to smectites (e.g., hectorite) remarkably rich intracrystalline reactivity compared with most other layered materials. Moreover, they are transparent and inert in most potential suspension media. Upon suspension in water, smectites readily swell. For homogeneous, melt-synthesized smectites, the degree of swelling can be tuned by choice of interlayer cation and charge density of the layer. Because swelling renders the clay stacks more shear labile, the efficiency of exfoliation by applying shearing forces can in turn be adjusted. Certain smectites even spontaneously delaminate into clay platelets of uniform thickness of 1 nm by progressive osmotic swelling. Osmotic swelling can also be applied to produce well-defined double stacks when one starts with ordered, interstratified heterostructures. Nanocomposites made with high-aspect-ratio fillers obtained this way show superior ...
TL;DR: In this paper, the synthesis and properties of nanosheets composing single or few layers of metal chalcogenides, boron nitride, BxCyNz, metal oxides, and metal-organic frameworks are discussed.
Abstract: In the last four to five years, there has been a great resurgence of research on two-dimensional inorganic materials, partly because of the impetus received from graphene research. Unlike graphene, which is a gap-less material, most inorganic layered materials are semiconductors or insulators. Some of them, as exemplified by MoS2, exhibit unexpected properties, not unlike graphene, with possible applications. Thus, layered metal chalcogenides are being explored intensely, and MoS2 is emerging as a wonder material. In this article, we present the synthesis and properties of nanosheets composing single or few layers of these fascinating materials. Besides metal chalcogenides, boron nitride, borocarbonitrides (BxCyNz), metal oxides, and metal-organic frameworks are also discussed.
TL;DR: In this paper, the authors discuss relevant structural features of single-component and multicomponent systems; provide a case study of the multifaceted structure that polymer:fullerene systems can adopt; and highlight relevant solidification mechanisms such as nucleation and growth, liquid-liquid phase separation, and spinodal decomposition.
Abstract: The structure of organic semiconductors can be complex because features from the molecular level (such as molecular conformation) to the micrometer scale (such as the volume fraction and composition of phases, phase distribution, and domain size) contribute to the definition of the optoelectronic landscape of the final architectures and, hence, to device performance. As a consequence, a detailed understanding of how to manipulate molecular ordering, e.g., through knowledge of relevant phase transitions, of the solidification process, of relevant solidification mechanisms, and of kinetic factors, is required to induce the desired optoelectronic response. In this review, we discuss relevant structural features of single-component and multicomponent systems; provide a case study of the multifaceted structure that polymer:fullerene systems can adopt; and highlight relevant solidification mechanisms such as nucleation and growth, liquid-liquid phase separation, and spinodal decomposition. In addition, cocrysta...
TL;DR: A review of the latest developments in the organization of artificial superlattice assemblies utilizing colloidal oxide or hydroxide nanosheets bearing a negative or positive charge can be found in this paper.
Abstract: This review covers some of the latest developments in the organization of artificial superlattice assemblies utilizing colloidal oxide or hydroxide nanosheets bearing a negative or positive charge, respectively. Various solution-based procedures, e.g., flocculation, electrostatic sequential adsorption, and Langmuir-Blodgett deposition, have been introduced for the self-assembly of 2D nanosheets. Superlattice composites or films integrated with different nanosheets may yield concerted or synergistic modulation, e.g., soft coupling or new electronic states at interfaces. This behavior offers an unprecedented opportunity for the exploration of high-performance devices, as well as advanced or novel functions that cannot be achieved with a single-component material.
TL;DR: In this paper, the fundamental concepts of reactive diffusion pathway analysis and kinetic biasing are used to design a multilayer Mo-Si-B-base coating with a phase sequencing that allows for structural and thermodynamic compatibility and an underlying diffusion barrier to maintain coating integrity.
Abstract: The synthesis of robust coatings that provide protection against environmental attack at ultrahigh temperatures is a difficult challenge. To achieve this goal for Mo-base alloys, the fundamental concepts of reactive diffusion pathway analysis and kinetic biasing are used to design a multilayer Mo-Si-B-base coating with a phase sequencing that allows for structural and thermodynamic compatibility and an underlying diffusion barrier to maintain coating integrity. The coating design concepts have a general applicability. The coating structure evolution during high-temperature exposure facilitates a prolonged lifetime as well as self-healing capability. The borosilicide coatings that can be synthesized by a pack cementation process yield superior environmental resistance for Mo-base systems at temperatures up to at least 1,700°C and can be adapted to apply to other refractory metal and ceramic systems.
TL;DR: In this paper, a mesoscopic discrete dislocation dynamics simulations with atomistically informed dislocation mobility laws were performed to investigate the influence of non-Schmid (nonglide) stresses on the mobility of screw dislocations in bcc metals.
Abstract: Significant progress in our understanding of plasticity in body-centered cubic (bcc) metals during the last decade has enabled rigorous multiscale modeling based on quantitative physical principles. Significant advances have been made at the atomistic level in the understanding of dislocation core structures and energetics associated with dislocation glide by using high-fidelity models originating from quantum mechanical principles. These simulations revealed important details about the influence of non-Schmid (nonglide) stresses on the mobility of screw dislocations in bcc metals that could be implemented to mesoscopic discrete dislocation simulations with atomistically informed dislocation mobility laws. First applications of dislocation dynamics simulations to studies of plasticity in small-scale bcc single crystals have been performed. Dislocation dynamics simulations inspired the development of continuum models based on advanced 3D dislocation density measures with evolution equations that naturally track dislocation motion. These advances open new opportunities and perspectives for future quantitative and materials-specific multiscale simulation methods to describe plastic deformation in bcc metals and their alloys.