The room-temperature manipulation of magnetization by an electric field using the multiferroic BiFeO3 represents an essential step towards the magnetoelectric control of spintronics devices.

Multiferroics: Towards a magnetoelectric memory

In the present review we try to give a comprehensive and most up to date view to the field, with an emphasis on the currently most investigated anodic TiO2 nanotube arrays. We will first give an overview of different synthesis approaches to produce TiO2 nanotubes and TiO2 nanotube arrays, and then deal with physical and chemical properties of TiO2 nanotubes and techniques to modify them. Finally, we will provide an overview of the most explored and prospective applications of nanotubular TiO2.

One-dimensional titanium dioxide nanomaterials: nanotubes.

Carbon nanotubes (CNTs) promise to advance a number of real-world technologies. Of these applications, they are particularly attractive for uses in chemical sensors for environmental and health monitoring. However, chemical sensors based on CNTs are often lacking in selectivity, and the elucidation of their sensing mechanisms remains challenging. This review is a comprehensive description of the parameters that give rise to the sensing capabilities of CNT-based sensors and the application of CNT-based devices in chemical sensing. This review begins with the discussion of the sensing mechanisms in CNT-based devices, the chemical methods of CNT functionalization, architectures of sensors, performance parameters, and theoretical models used to describe CNT sensors. It then discusses the expansive applications of CNT-based sensors to multiple areas including environmental monitoring, food and agriculture applications, biological sensors, and national security. The discussion of each analyte focuses on the strategies used to impart selectivity and the molecular interactions between the selector and the analyte. Finally, the review concludes with a brief outlook over future developments in the field of chemical sensors and their prospects for commercialization.

Carbon Nanotube Chemical Sensors

A current drawback of spintronics is the large power that is usually required for magnetic writing, in contrast with nanoelectronics, which relies on "zero-current," gate-controlled operations. Efforts have been made to control the spin-relaxation rate, the Curie temperature, or the magnetic anisotropy with a gate voltage, but these effects are usually small and volatile. We used ferroelectric tunnel junctions with ferromagnetic electrodes to demonstrate local, large, and nonvolatile control of carrier spin polarization by electrically switching ferroelectric polarization. Our results represent a giant type of interfacial magnetoelectric coupling and suggest a low-power approach for spin-based information control.

https://science.sciencemag.org/content/sci/327/5969/1106.full.pdf

Ferroelectric Control of Spin Polarization

The growth and characterization of functional oxide thin films that are ferroelectric, magnetic, or both at the same time are reviewed. The evolution of synthesis techniques and how advances in in situ characterization have enabled significant acceleration in improvements to these materials are described. Methods for enhancing the properties of functional materials or creating entirely new functionality at interfaces are covered, including strain engineering and layering control at the atomic-layer level. Emerging applications of these functional oxides such as achieving electrical control of ferromagnetism and the future of these complex functional oxides is discussed.

/pdf/advances-in-the-growth-and-characterization-of-magnetic-1r6yol3qt6.pdf

Advances in the growth and characterization of magnetic, ferroelectric, and multiferroic oxide thin films

Using first-principles theory, we investigated the most stable configuration for the Rh dopant on a MoSe2 monolayer, and the interaction of the Rh-doped MoSe2 (Rh-MoSe2) monolayer with four toxic gases (CO, NO, NO2 and SO2) to exploit the potential application of the Rh-MoS2 monolayer as a gas sensor or adsorbent. Based on adsorption behavior comparison with other 2D adsorbents and desorption behavior analysis, we assume that the Rh-MoSe2 monolayer is a desirable adsorbent for CO, NO and NO2 storage or removal given the larger adsorption energy (Ead) of −2.00, −2.56 and −1.88 eV, respectively, compared with other materials. In the meanwhile, the Rh-MoSe2 monolayer is a good sensing material for SO2 detection according to its desirable adsorption and desorption behaviors towards the target molecule. Our theoretical calculation would provide a first insight into the TM-doping effect on the structural and electronic properties of the MoSe2 monolayer, and shed light on the application of Rh-MoSe2 for the sensing or disposal of common toxic gases.

/pdf/rh-doped-mose2-as-a-toxic-gas-scavenger-a-first-principles-1hkyclmg1o.pdf

Rh-doped MoSe2 as a toxic gas scavenger: a first-principles study

Pd-doped MoS2 monolayer: A promising candidate for DGA in transformer oil based on DFT method

Partial discharge (PD) is usually aroused before the failure of gas insulated switchgear (GIS) caused by defects, which results in the decomposition of the SF6 used as insulating gas. Analyzing SF6 decomposition products can aid in PD detection. Before recognizing PD types by analyzing SF6 decomposition products, the decomposition characteristics of SF6 under different types of PD should be investigated first. In this paper, a gas chamber and four typical types of artificial defects were designed to simulate the SF6 decomposition phenomenon under PD in GIS. A gas chromatography system was established to detect SF6 decomposition products. By selecting the chromatographic column, SF6 decomposition products were successfully separated and their concentrations were measured. Numerous SF6 decomposition experiments under four kinds of PD generated by four kinds of artificial defects were carried out and the SF6 decomposition products produced by each experiment were detected. The decomposition characteristics of SF6 under the four defects were different in terms of decomposition amount, generation rate, and concentration ratio, among others. It is feasible to recognize the type of PD by analyzing SF6 decomposition products.

Partial discharge recognition through an analysis of SF 6 decomposition products part 1: decomposition characteristics of SF 6 under four different partial discharges

Pristine and Cu decorated hexagonal InN monolayer, a promising candidate to detect and scavenge SF6 decompositions based on first-principle study.

The decomposition characteristics of the SF6 under the different kinds of partial discharges (PD) should be understood first when recognizing PD by analyzing SF6 decomposition products in gas insulated switchgear (GIS). Moreover, the characteristic quantities used for recognition must be found. In this paper, the concentration and concentration ratio of SF6 decomposition products were each selected as characteristic quantities. Fuzzy c-means clustering algorithm was adopted to assess the performance of the two types of characteristic quantities, which was based on the data of SF6 decomposition products under the four kinds of PD in Part 1. Concentration ratio had better performance than concentration as a characteristic quantity in PD recognition. The concentration ratio method for PD recognition was established based on the decision tree theory, in which the three concentration ratios, namely c(SOF2)/c(SO2F2), c(CF4)/c(CO2), and c(SOF2 +SO2F2)/c(CO2+CF4), were used as characteristic quantities. The physical significance of the three concentration ratios was also analyzed. Finally, the concentration ratio method was applied to test the performance of PD recognition. The method has a good performance and can successfully recognize different kinds of PD.

Partial discharge recognition through an analysis of SF 6 decomposition products part 2: feature extraction and decision tree-based pattern recognition

Ju Tang

Papers

Rh-doped MoSe2 as a toxic gas scavenger: a first-principles study

Pd-doped MoS2 monolayer: A promising candidate for DGA in transformer oil based on DFT method

Partial discharge recognition through an analysis of SF 6 decomposition products part 1: decomposition characteristics of SF 6 under four different partial discharges

Pristine and Cu decorated hexagonal InN monolayer, a promising candidate to detect and scavenge SF6 decompositions based on first-principle study.

Partial discharge recognition through an analysis of SF 6 decomposition products part 2: feature extraction and decision tree-based pattern recognition