Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
1.
Int J Mol Sci ; 24(20)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37895162

RESUMEN

Oral inflammatory diseases (OIDs) include many common diseases such as periodontitis and pulpitis. The causes of OIDs consist microorganism, trauma, occlusal factors, autoimmune dis-eases and radiation therapy. When treated unproperly, such diseases not only affect oral health but also pose threat to people's overall health condition. Therefore, identifying OIDs at an early stage and exploring new therapeutic strategies are important tasks for oral-related research. Mitochondria are crucial organelles for many cellular activities and disruptions of mitochondrial function not only affect cellular metabolism but also indirectly influence people's health and life span. Mitochondrial dysfunction has been implicated in many common polygenic diseases, including cardiovascular and neurodegenerative diseases. Recently, increasing evidence suggests that mitochondrial dysfunction plays a critical role in the development and progression of OIDs and its associated systemic diseases. In this review, we elucidated the critical insights into mitochondrial dysfunction and its involvement in the inflammatory responses in OIDs. We also summarized recent research progresses on the treatment of OIDs targeting mitochondrial dysfunction and discussed the underlying mechanisms.


Asunto(s)
Enfermedades Mitocondriales , Periodontitis , Pulpitis , Humanos , Estrés Oxidativo/fisiología , Mitocondrias/metabolismo , Periodontitis/etiología , Periodontitis/terapia , Periodontitis/metabolismo , Longevidad , Pulpitis/metabolismo , Enfermedades Mitocondriales/etiología , Enfermedades Mitocondriales/terapia , Enfermedades Mitocondriales/metabolismo
2.
Nano Lett ; 19(5): 3057-3065, 2019 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-30964306

RESUMEN

Complex oxide thin-film heterostructures often exhibit magnetic properties different from those known for bulk constituents. This is due to the altered local structural and electronic environment at the interfaces, which affects the exchange coupling and magnetic ordering. The emergent magnetism at oxide interfaces can be controlled by ferroelectric polarization and has a strong effect on spin-dependent transport properties of oxide heterostructures, including magnetic and ferroelectric tunnel junctions. Here, using prototype La2/3Sr1/3MnO3/BaTiO3 heterostructures, we demonstrate that ferroelectric polarization of BaTiO3 controls the orbital hybridization and magnetism at heterointerfaces. We observe changes in the enhanced orbital occupancy and significant charge redistribution across the heterointerfaces, affecting the spin and orbital magnetic moments of the interfacial Mn and Ti atoms. Importantly, we find that the exchange coupling between Mn and Ti atoms across the interface is tuned by ferroelectric polarization from ferromagnetic to antiferromagnetic. Our findings provide a viable route to electrically control complex magnetic configurations at artificial multiferroic interfaces, taking a step toward low-power spintronics.

3.
Chemistry ; 24(58): 15589-15595, 2018 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-29959855

RESUMEN

For the last decades, the chemical reduction of Au3+ to Au0 has been widely employed to produce various gold nanostructures. In comparison with the fast reduction, the slow reduction is systematically investigated in this research to provide more insights to reveal intermediary process and further disclose the underlying mechanism for growing gold nanostructures by using a series of simple ligands with aldehyde groups as weak reducing agents. The different binding energies of ligands to Aun+ (n=3, 1 and 0) exhibit variable binding affinities in starting, intermediate, and final gold species. For example, formic acid has much stronger binding affinity to Au+ than Au3+ , and thus Au+ intermediate is able to be stabilized/captured during slow reduction of Au3+ . Upon the disproportionation of Au+ to Au0 and Au3+ , formic acid has much stronger binding affinity to the newly formed Au0 than other ligands for the controlled formation of gold nanostructures. Meanwhile, the adsorption of ligands causes substantially decreased surface energies on different gold planes. There are much higher energies on {110} planes compared to the other two {111} and {100} planes with certain ratios in these energies, leading to morphological growth of gold nanosheets. In this paper, we experimentally demonstrate anisotropic growth of gold nanosheets by using various ligands with weak reducing and appropriate coordination capabilities, and further provide insights to understand their morphological growth mechanism behind. This synthetic strategy is successfully extended to prepare silver, palladium, and platinum nanoplates.

4.
Small ; 11(5): 576-84, 2015 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-25227572

RESUMEN

Materials with mesoscopic structural and electronic phase separation, either inherent from synthesis or created via external means, are known to exhibit functionalities absent in the homogeneous counterparts. One of the most notable examples is the colossal magnetoresistance discovered in mixed-valence manganites, where the coexistence of nano- to micrometer-sized phase-separated domains dictates the magnetotransport. However, it remains challenging to pattern and process such materials into predesigned structures and devices. In this work, a direct laser interference irradiation (LII) method is employed to produce periodic stripes in thin films of a prototypical phase-separated manganite Pr0.65 (Ca0.75 Sr0.25 )0.35 MnO3 (PCSMO). LII induces selective structural amorphization within the crystalline PCSMO matrix, forming arrays with dimensions commensurate with the laser wavelength. Furthermore, because the length scale of LII modification is compatible to that of phase separation in PCSMO, three orders of magnitude of increase in magnetoresistance and significant in-plane transport anisotropy are observed in treated PCSMO thin films. Our results show that LII is a rapid, cost-effective and contamination-free technique to tailor and improve the physical properties of manganite thin films, and it is promising to be generalized to other functional materials.

5.
Inorg Chem ; 54(23): 11356-61, 2015 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-26562353

RESUMEN

Thorium silicate apatite with the formula [Ca3.84Th0.16]F[Ca2.79Th3.21]T(SiO4)6O2 · x(H) was synthesized by solid-state reaction, and its structure refined in P63/m from powder X-ray diffraction (XRD) data using the Rietveld method (a = 9.50172(9) Å, c = 6.98302(8) Å, V = 545.98(1) Å(3); R-Bragg = 2.102%). It was found that thorium partitions strongly to the tunnel (T) 6h position rather than the framework (F) 4f site. Fourier transform infrared spectroscopy revealed only SiO4 tetrahedron, with SiO5 and SiO6 groups, sometimes observed in siliceous apatites absent, at least to the limit of detection of this technique. Thermal expansion of the thorium apatite determined by high-temperature XRD from 298-1173 K found Δa (0.87%) dilation to exceed Δc (0.73%) with increasing temperature consistent with other silicate apatites.

6.
Nano Lett ; 14(5): 2419-25, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24678857

RESUMEN

We present successful synthesis of large area atomically thin MoSe2 films by selenization of MoO3 in a vapor transport chemical vapor deposition (CVD) system. The homogeneous thin film can reach an area of 1 × 1 cm(2) consisting primarily of monolayer and bilayer MoSe2 film. Scanning transmission electron microscopy (STEM) images reveal the highly crystalline nature of the thin film and the atomic structure of grain boundaries in monolayers. Raman and photoluminescence spectroscopy confirm the high quality of as-grown MoSe2 in optics, and electronic transport measurements highlight the potential applications of the sample in nanoelectronics.

7.
Angew Chem Int Ed Engl ; 53(49): 13488-92, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25168684

RESUMEN

The fundamental understanding of the relationship between the nanostructure of an electrode and its electrochemical performance is crucial for achieving high-performance lithium-ion batteries (LIBs). In this work, the relationship between the nanotubular aspect ratio and electrochemical performance of LIBs is elucidated for the first time. The stirring hydrothermal method was used to control the aspect ratio of viscous titanate nanotubes, which were used to fabricate additive-free TiO2 -based electrode materials. We found that the battery performance at high charging/discharging rates is dramatically boosted when the aspect ratio is increased, due to the optimization of electronic/ionic transport properties within the electrode materials. The proof-of-concept LIBs comprising nanotubes with an aspect ratio of 265 can retain more than 86 % of their initial capacity over 6000 cycles at a high rate of 30 C. Such devices with supercapacitor-like rate performance and battery-like capacity herald a new paradigm for energy storage systems.


Asunto(s)
Suministros de Energía Eléctrica , Litio/química , Nanotubos/química , Titanio/química , Electrodos , Nanotubos/ultraestructura
8.
Cell Death Discov ; 10(1): 195, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38670955

RESUMEN

Periodontitis is a highly prevalent disease characterized by inflammation and destruction of tooth-supporting tissues that leads to tooth loss in extreme situations. Elucidating the underlying mechanisms of periodontitis pathogenesis and progression will establish the groundwork for developing effective treatment strategies. Recently, evidence concerning the role of ferroptosis in periodontitis progression has emerged. Osteogenic lineage cells are key regulators of bone remodeling. Osteogenic cell death, as observed in experimental periodontitis models, disrupts the balance between bone resorption and bone formation. However, whether the osteogenic lineage undergoes ferroptosis during periodontitis and the corresponding effect on periodontitis progression remain elusive. Here, we investigated cell-specific ferroptosis within the alveolar bone in a murine periodontitis model. Through immunofluorescence double staining and immunohistochemistry, we identified ferroptotic osteocytes and osteoblasts in inflammatory alveolar bone. Next, in vivo administration of erastin or liproxstatin-1 was conducted to either induce or inhibit ferroptosis, respectively. Severe bone resorption and inflammation, accompanied by increased osteoclast formation and impaired osteogenic potential were detected following ferroptosis activation. Subsequently, we carried out in vitro experiments on osteocytes and further verified that ferroptosis enhanced the osteocytic expression of RANKL and IL-6. These findings suggest that ferroptosis occurring within the osteogenic lineage acts as a catalyst in the progression of periodontitis by stimulating osteoclastogenesis through the secretion of inflammatory cytokines and inhibiting osteoblastic function, providing insights into ferroptosis-induced alterations in microenvironment-based intercellular communication. Ferroptosis is a promising target for controlling inflammation and preventing bone resorption in periodontitis.

9.
Small ; 9(5): 705-10, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23161845

RESUMEN

New Type of Gold Nanoparticle: A new class of fivefold stellate polyhedral gold nanoparticles (FSPAuNPs) with {110} facets have been synthesized by a seed-mediated growth method without adding surfactant. The size of FSPAuNPs can be simply adjusted from nanoscale to microscale by varying the amount of seeds, which results in a shift of the surface plasmon resonance peak from the visible to the NIR range.

10.
Small ; 9(7): 996-1002, 2013 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-23239592

RESUMEN

3D Hierarchical echinus-like titanate spheres (HETSs), serving as the supporting material for CdS nanoparticles, are synthesized via a fast one-step hydrothermal method. The obtained 3D CdS-HETS composite materials show enhanced H2 generation under visible light irradiation.


Asunto(s)
Compuestos de Cadmio/química , Hidrógeno/química , Luz , Nanocompuestos/química , Compuestos de Selenio/química , Titanio/química , Fotoquímica/métodos
11.
Nano Lett ; 12(8): 4305-10, 2012 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-22823516

RESUMEN

Control of competing parameters such as thermoelectric (TE) power and electrical and thermal conductivities is essential for the high performance of thermoelectric materials. Bulk-nanocomposite materials have shown a promising improvement in the TE performance due to poor thermal conductivity and charge carrier filtering by interfaces and grain boundaries. Consequently, it has become pressingly important to understand the formation mechanisms, stability of interfaces and grain boundaries along with subsequent effects on the physical properties. We report here the effects of the thermodynamic environment during spark plasma sintering (SPS) on the TE performance of bulk-nanocomposites of chemically synthesized Bi(2)Te(2.7)Se(0.3) nanoplatelets. Four pellets of nanoplatelets powder synthesized in the same batch have been made by SPS at different temperatures of 230, 250, 280, and 350 °C. The X-ray diffraction, transmission electron microscopy, thermoelectric, and thermal transport measurements illustrate that the pellet sintered at 250 °C shows a minimum grain growth and an optimal number of interfaces for efficient TE figure of merit, ZT∼0.55. For the high temperature (350 °C) pelletized nanoplatelet composites, the concurrent rise in electrical and thermal conductivities with a deleterious decrease in thermoelectric power have been observed, which results because of the grain growth and rearrangements of the interfaces and grain boundaries. Cross section electron microscopy investigations indeed show significant grain growth. Our study highlights an optimized temperature range for the pelletization of the nanoplatelet composites for TE applications. The results provide a subtle understanding of the grain growth mechanism and the filtering of low energy electrons and phonons with thermoelectric interfaces.

12.
Mater Horiz ; 10(10): 4243-4250, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37555343

RESUMEN

The energy efficiency of buildings has become a critical issue due to their substantial contribution to global energy consumption. Windows, in particular, are often the least efficient component of the building envelope, and conventional smart windows focus solely on regulating solar transmittance while overlooking radiative cooling. Although several recent designs achieved dual-control of solar and radiative cooling, these windows still face limitations in terms of durability, limited modulation ability and energy-saving performance. To address these challenges, we propose a novel dual-control smart window design consisting of a reconfigurable kirigami structure and polydimethylsiloxane-laminated thermochromic hydrogel coated with silver nanowires. In summer, the thermochromic hydrogel turns translucent to suppress the solar heat gain, while the high emissivity kirigami structure covers the exterior surface of the window, promoting radiative cooling. In winter, the hydrogel becomes transparent to allow for solar transmission. Additionally, the kirigami structure undergoes an out-of-plane structural change, opening towards the outside environment to expose the underlying low-emissivity silver nanowires and suppress heat radiation. Our design achieves a promising solar transmittance modulation ability of ∼24% and a good long-wave infrared emissivity regulation ability of 0.5. Furthermore, it exhibits significantly improved durability, which is nine times longer than the lifespan of conventional smart hydrogels. Our novel approach offers a promising solution for constructing energy-efficient and durable smart windows and outperforms existing state-of-the-art solar/radiative cooling dual-regulation smart windows in the literature.

13.
Adv Mater ; 35(12): e2208954, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36647621

RESUMEN

Spin-orbit torque (SOT)-induced switching of perpendicular magnetization in the absence of magnetic field is crucial for the application of SOT-based spintronic devices. Recent works have demonstrated that the low-symmetry crystal structure in CuPt/CoPt can give rise to an out-of-plane (OOP) spin torque and lead to deterministic magnetization switching without an external field. However, it is essential to improve OOP effective field for the efficient switching. In this work, the impact of interface oxidation on the generation of OOP effective field in a CuPt/ferromagnet heterostructure is systematically studied. By introducing an oxidized CuPt surface, it is found that the field-free switching performance shows remarkable improvement. OOP effective field measurement indicates that the oxidation treatment can enhance the OOP effective field by more than two times. It is also demonstrated that this oxidation-induced OOP SOT efficiency enhancement is independent of the device shapes, magnetic materials, or magnetization easy axis. This work contributes to improve the performance of SOT devices and provides an effective fabrication guidance for future spintronic devices that utilize OOP SOT.

14.
Adv Mater ; 35(46): e2306330, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37737448

RESUMEN

Due to its inversion-broken triple helix structure and the nature of Weyl semiconductor, 2D Tellurene (2D Te) is promising to possess a strong nonlinear optical response in the infrared region, which is rarely reported in 2D materials. Here, a giant nonlinear infrared response induced by large Berry curvature dipole (BCD) is demonstrated in the Weyl semiconductor 2D Te. Ultrahigh second-harmonic generation response is acquired from 2D Te with a large second-order nonlinear optical susceptibility (χ(2) ), which is up to 23.3 times higher than that of monolayer MoS2 in the range of 700-1500 nm. Notably, distinct from other 2D nonlinear semiconductors, χ(2) of 2D Te increases extraordinarily with increasing wavelength and reaches up to 5.58 nm V-1 at ≈2300 nm, which is the best infrared performance among the reported 2D nonlinear materials. Large χ(2) of 2D Te also enables the high-intensity sum-frequency generation with an ultralow continuous-wave (CW) pump power. Theoretical calculations reveal that the exceptional performance is attributed to the presence of large BCD located at the Weyl points of 2D Te. These results unravel a new linkage between Weyl semiconductor and strong optical nonlinear responses, rendering 2D Te a competitive candidate for highly efficient nonlinear 2D semiconductors in the infrared region.

15.
Chemistry ; 18(49): 15693-8, 2012 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-23060239

RESUMEN

Unique DNA-promoted Pd nanocrystals on carbon nanotubes (Pd/DNA-CNTs) are synthesized for the first time, in which through its regularly arranged PO(4)(3-) groups on the sugar-phosphate backbone, DNA directs the growth of ultrasmall Pd nanocrytals with an average size of 3.4 nm uniformly distributed on CNTs. The Pd/DNA-CNT catalyst shows much more efficient electrocatalytic activity towards oxygen reduction reaction (ORR) with a much more positive onset potential, higher catalytic current density and better stability than other Pd-based catalysts including Pd nanocrystals on carbon nanotubes (Pd/CNTs) without the use of DNA and commercial Pd/C catalyst. In addition, the Pd/DNA-CNTs catalyst provides high methanol tolerance. The high electrocatalytic performance is mainly contributed by the ultrasmall Pd nanocrystal particles grown directed by DNA to enhance the mass transport rate and to improve the utilization of the Pd catalyst. This work may demonstrate a universal approach to fabricate other superior metal nanocrystal catalysts with DNA promotion for broad applications in energy systems and sensing devices.


Asunto(s)
ADN/química , Nanopartículas del Metal/química , Nanopartículas/química , Nanotubos de Carbono/química , Paladio/química , Catálisis , Oxidación-Reducción
16.
J Tissue Eng Regen Med ; 16(9): 775-787, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35716051

RESUMEN

Orofacial mesenchymal stromal cells (OFMSCs) are mesenchymal stromal cells isolated from the oral and facial regions, which possess typical mesenchymal stromal cell features such as self-renewing, multilineage differentiation, and immunoregulatory properties. Recently, increasing studies have been carried out on the neurotrophic and neuroregenerative properties of OFMSCs as well as their potential to treat neurological diseases. In this review, we summarize the current evidence and discuss the prospects regarding the therapeutic potential of OFMSCs as a new approach to treat different neurological diseases and injuries.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Diferenciación Celular , Regeneración Nerviosa
17.
Microb Biotechnol ; 15(2): 548-560, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34676986

RESUMEN

The recent COVID-19 virus has led to a rising interest in antimicrobial and antiviral coatings for frequently touched surfaces in public and healthcare settings. Such coatings may have the ability to kill a variety of microorganisms and bio-structures and reduce the risk of virus transmission. This paper proposes an extremely rapid method to introduce rare-earth doping nano-ZnO in polyamines for the preparation of the anti-microbial polyurea coatings. The nano-ZnO is prepared by wet chemical method, and the RE-doped nano-ZnO was obtained by mixing nano ZnO and RE-dopants with an appropriate amount of nitric acid. This rapidly fabricated polyurea coating can effectively reduce bacteria from enriching on the surface. Comparing with pure nano-ZnO group, all the polyurea coatings with four different rare-earth elements (La, Ce, Pr and Gd) doped nano-ZnO. The La-doped nano-ZnO formula group indicates the highest bactericidal rate over 85% to Escherichia coli (E. coli) and Pseudomonas aeruginosa (Pseudomonas). Followed by Ce/ZnO, the bactericidal rate may still remain as high as 83% at room temperature after 25-min UV-exposure. It is believed that the RE-doping process may greatly improve the photocatalytic response to UV light as well as environmental temperature due to its thermal catalytic enhancement. Through the surface characterizations and bioassays, the coatings have a durably high bactericidal rate even after repeated usage. As polyurea coating itself has high mechanical strength and adhesive force with most substrate materials without peel-off found, this rapid preparation method will also provide good prospects in practical applications.


Asunto(s)
Antiinfecciosos , COVID-19 , Óxido de Zinc , Antiinfecciosos/farmacología , Escherichia coli , Humanos , Polímeros , SARS-CoV-2 , Óxido de Zinc/química , Óxido de Zinc/farmacología
18.
Chemosphere ; 286(Pt 3): 131869, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34418655

RESUMEN

Improving the efficiencies of organic compound degradations by catalytic materials is a challenging materials research field. In our research, we successfully synthesized cobalt-based polyoxometalates (CoV-POMs) via a simple crystallization-driven self-assembly method. The incorporation of the newly synthesized CoV-POMs into peroxymonosulphate (PMS), forming a mixture, greatly enhancing the catalytic activation for a complete degradation of dye solution. The positive synergic effect between CoV-POMs and PMS was substantiated by a relatively meager degradation of less than 10% in the system without CoV-POMs, in which CoV-POMs played a vital role to activate PMS towards free radicals generation for dye degradation. Methylene blue (MB) and rhodamine B (RB) dyes were completely decolorized under 60 min with the presence of 40 mg/L CoV-POMs and 150 mg/L PMS. The CoV-POMs/PMS system was pH dependance with a lower dye degradation efficiency at elevated pH. The effect of pH was more prominent in RB dye, in which the degradation efficiency dropped drastically from 93.3% to 41.12% with the increase in the solution pH from 7 to 11. The quenching tests suggested that sulfate radicals were the dominant active species involving in the dye degradation reaction. Besides MB and RB dyes, CoV-POMs/PMS system also showed significant activity towards the degradation of phenol red (PR) and methyl orange (MO) dyes. In the biological test, CoV-POMs exhibited non-toxic behavior towards normal cells that reduced safety concern for the large-scale wastewater treatment application. In addition, the testing divulged the anticancer property of CoV-POMs with more than 35 % of A549 lung adenocarcinoma and MDA-MB-231 breast adenocarcinoma were killed with 250 mg/L CoV-POMs. The selective lethality of CoV-POMs towards cancer cells was found to be caused by different extents of cellular apoptosis. In overall, the synthesized bifunctional CoV-POMs manifested superior activities in the examined applications, specifically dye degradation and anticancer.


Asunto(s)
Colorantes , Compuestos de Tungsteno , Catálisis , Cobalto
19.
ACS Appl Mater Interfaces ; 14(19): 22030-22040, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35466672

RESUMEN

Tungsten disulfide (WS2) is well known to have great potential as an electrocatalyst, but the practical application is hampered by its intrinsic inert plane and semiconductor properties. In this work, owing to a Co-based zeolite imidazole framework (ZIF-67) that effectively inhibited WS2 growth, few-layered WS2 was confined to the surface of Co, N-doped carbon polyhedron (WS2@Co9S8), with more marginal active sites and higher conductivity, which promoted efficient oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). For the first time, WS2@Co9S8 was prepared by mixing in one pot of a liquid phase and calcination, and WS2 realized uniform distribution on the polyhedron surface by electrostatic adsorption in the liquid phase. The obtained hybrid catalyst exhibited excellent OER and HER catalytic activity, and the OER potential was only 15 mV at 10 mA cm-2 higher than that of noble metal oxide (RuO2). The improvement of catalytic activity can be attributed to the enhanced exposure of sulfur edge sites by WS2, the unique synergistic effect between WS2 and Co9S8 on the metal-organic framework (MOF) surface, and the effective shortening of the diffusion path by the hollow multi-channel structure. Therefore, the robust catalyst (WS2@Co9S8) prepared by a simple and efficient synthesis method in this work will serve as a highly promising bifunctional catalyst for OER and HER.

20.
Nat Commun ; 13(1): 3539, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725723

RESUMEN

All-electric switching of perpendicular magnetization is a prerequisite for the integration of fast, high-density, and low-power magnetic memories and magnetic logic devices into electric circuits. To date, the field-free spin-orbit torque (SOT) switching of perpendicular magnetization has been observed in SOT bilayer and trilayer systems through various asymmetric designs, which mainly aim to break the mirror symmetry. Here, we report that the perpendicular magnetization of CoxPt100-x single layers within a special composition range (20 < x < 56) can be deterministically switched by electrical current in the absence of external magnetic field. Specifically, the Co30Pt70 shows the largest out-of-plane effective field efficiency and best switching performance. We demonstrate that this unique property arises from the cooperation of two structural mechanisms: the low crystal symmetry property at the Co platelet/Pt interfaces and the composition gradient along the thickness direction. Compared with that in bilayers or trilayers, the field-free switching in CoxPt100-x single layer greatly simplifies the SOT structure and avoids additional asymmetric designs.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA