•The typical texture in wrought Mg alloy and its effect on mechanical properties.•Texture evolution during alloying or processing.•The mechanism of texture weakening.
The crystallographic ...orientations are generally non-random in wrought Mg alloy, which will lead to their macroscopic physical properties to be anisotropic. Understanding the texture evolution in processing of Mg alloy billets and its effect on mechanical properties is therefore an important project for all scientists and engineers in material area. This paper is concerned with the description of texture, with the mechanisms of texture evolution and with the interrelationships between texture and mechanical properties in Mg alloy. It is a full review of understanding of the basic mechanism on texture evolution, of texture altering by alloying or processing, and of the mechanism of texture weakening. Moreover, it provides theories necessary and available techniques to develop high-performance Mg wrought with optimized texture in the field.
Multiferroics are those materials with more than one ferroic order, and magnetoelectricity refers to the mutual coupling between magnetism (spins and/or magnetic field) and electricity (electric ...dipoles and/or electric field). In spite of the long research history in the whole twentieth century, the discipline of multiferroicity has never been so highly active as that in the first decade of the twenty-first century, and it has become one of the hottest disciplines of condensed matter physics and materials science. A series of milestones and steady progress in the past decade have enabled our understanding of multiferroic physics substantially comprehensive and profound, which is further pushing forward the research frontier of this exciting area. The availability of more multiferroic materials and improved magnetoelectric performance are approaching to make the applications within reach. While seminal review articles covering the major progress before 2010 are available, an updated review addressing the new achievements since that time becomes imperative. In this review, following a concise outline of the basic knowledge of multiferroicity and magnetoelectricity, we summarize the important research activities on multiferroics, especially magnetoelectricity and related physics in the last six years. We consider not only single-phase multiferroics but also multiferroic heterostructures. We address the physical mechanisms regarding magnetoelectric coupling so that the backbone of this divergent discipline can be highlighted. A series of issues on lattice symmetry, magnetic ordering, ferroelectricity generation, electromagnon excitations, multiferroic domain structure and domain wall dynamics, and interfacial coupling in multiferroic heterostructures, will be revisited in an updated framework of physics. In addition, several emergent phenomena and related physics, including magnetic skyrmions and generic topological structures associated with magnetoelectricity will be discussed. The review is ended with a set of prospectives and forward-looking conclusions, which may inevitably reflect the authors' biased opinions but are certainly critical.
ABSTRACT
The key physical property of multiferroic materials is the existence of coupling between magnetism and polarization, i.e. magnetoelectricity. The origin and manifestations of ...magnetoelectricity can be very different in the available plethora of multiferroic systems, with multiple possible mechanisms hidden behind the phenomena. In this review, we describe the fundamental physics that causes magnetoelectricity from a theoretical viewpoint. The present review will focus on mainstream physical mechanisms in both single-phase multiferroics and magnetoelectric heterostructures. The most recent tendencies addressing possible new magnetoelectric mechanisms will also be briefly outlined.
Ti2O3 nanoparticles with high performance of photothermal conversion are demonstrated for the first time. Benefiting from the nanosize and narrow‐bandgap features, the Ti2O3 nanoparticles possess ...strong light absorption and nearly 100% internal solar–thermal conversion efficiency. Furthermore, Ti2O3‐nanoparticle‐based thin film shows potential use in seawater desalination and purification.
This topical review focuses on the recently active debate on the band alignment between two polymorphs of TiO2, rutile and anatase. A summary is given to the popular methods for measurement and ...calculation of band alignment between materials. We point out, through examination of recently experimental and theoretical reports, that the outstanding discrepancy in the band alignment between two TiO2 phases is attributed to factors that influence band alignment rather than needs a definite answer of which band alignment is right. According to an important factor, the presence of an interface, a new classification of band alignment is proposed as the coupled and intrinsic band alignments. This classification indeed reveals that the rutile/anatase interface can qualitatively change the type of their band alignment. However, further systematic information of the interface and other factors that influence band alignment will be needed to better understand changes in energy bands of materials. The results obtained from discussion of the band alignment between rutile and anatase may also work for the band alignment between other semiconductors.
This topical review focuses on the recently active debate on the band alignment between rutile and anatase TiO2, and points out that factors such as the rutile/anatase interface influence their band alignment. Display omitted
•The discrepancy in the band alignment between the rutile and anatase TiO2 is attributed to factors that influence band alignment.•An interface is one of the most important factors that influence the band alignment.•There is a need of a systematic study for the effect of these factors mentioned in this topical review on the band alignment.
Gas sensors have attracted much attentions due to their applications for alarming dangerous gases. It is important for a gas sensor to find out suitable sensing materials realizing its performance. ...Two-dimensional materials with high surface-to-volume ratios are ideal candidates acting as gas-sensing materials. Here, we report NO
2
and SO
2
gas-sensing properties of InX (X = Cl, Br, and I) monolayers based on density functional theory calculations. The perfect monolayers are more sensitive to NO
2
molecule than SO
2
, but have long recovery time for NO
2
, which can be amended by applying external in-plane tensile stress. Therefore, these monolayers with the tensile stress are good materials for detecting NO
2
gas. In addition, the sensitivity of monolayers to detect the SO
2
molecule can be significantly improved by introducing In vacancies into these monolayers.
Graphical Abstract
Nowadays the development of machine vision is oriented toward real-time applications such as autonomous driving. This demands a hardware solution with low latency, high energy efficiency, and good ...reliability. Here, we demonstrate a robust and self-powered in-sensor computing paradigm with a ferroelectric photosensor network (FE-PS-NET). The FE-PS-NET, constituted by ferroelectric photosensors (FE-PSs) with tunable photoresponsivities, is capable of simultaneously capturing and processing images. In each FE-PS, self-powered photovoltaic responses, modulated by remanent polarization of an epitaxial ferroelectric Pb(Zr
Ti
)O
layer, show not only multiple nonvolatile levels but also sign reversibility, enabling the representation of a signed weight in a single device and hence reducing the hardware overhead for network construction. With multiple FE-PSs wired together, the FE-PS-NET acts on its own as an artificial neural network. In situ multiply-accumulate operation between an input image and a stored photoresponsivity matrix is demonstrated in the FE-PS-NET. Moreover, the FE-PS-NET is faultlessly competent for real-time image processing functionalities, including binary classification between 'X' and 'T' patterns with 100% accuracy and edge detection for an arrow sign with an F-Measure of 1 (under 365 nm ultraviolet light). This study highlights the great potential of ferroelectric photovoltaics as the hardware basis of real-time machine vision.
Since the discovery of graphene, two-dimensional materials with atomic level thickness have rapidly grown to be a prosperous field of physical science with interdisciplinary interest for their ...fascinating properties and broad applications. Very recently, the experimental observation of ferromagnetism in a Cr2Ge2Te6 bilayer and a CrI3 monolayer opened a door to pursue long-absent intrinsic magnetic orders in two-dimensional materials. Meanwhile, the ferroelectricity was also experimentally found in a SnTe monolayer and CuInP2S6 few layers. The emergence of these ferroic orders in the two-dimensional limit not only brings new challenges to our physical knowledge but also provides more functionalities for potential applications. Among various two-dimensional ferroic ordered materials, transition/rare-earth metal halides and their derivants are very common. In this Research Update, based on transition/rare-earth metal halides, the physics of various ferroic orders in two-dimensional materials will be illustrated. The potential applications based on their magnetic and polar properties will also be discussed.
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