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A ruthenium doped MoS2/AB heterostructure is synthesized as a highly efficient and durable electrocatalyst, in which the Ru near S is demonstrated as optimum active sites for hydrogen evolution reaction in water electrolysis.

The high penetration of distributed generators (DGs) and the large-scale charging loads deteriorate the operational status of flexible distribution networks (FDNs). A soft open point (SOP) can deal with operational issues, such as voltage violations and the high electricity purchasing cost of charging stations. However, the absence of accurate parameters poses challenges to model-based methods. This paper proposes a data-driven operation method of FDNs with charging loads. First, a data-driven model-free adaptive predictive control (MFAPC) approach is proposed to fully involve charging loads in the control of FDN without accurate network parameters. Then, a multi-timescale coordination control model of an SOP with charging loads is established to satisfy the demand of charging loads and improve the control performance. The effectiveness of the proposed method is numerically demonstrated on the modified IEEE 33-node distribution network. The results indicate that the proposed method can effectively reduce the electricity purchasing cost of charging stations and improve the operational performance of FDNs.

Developing a highly efficient, nonprecious, and stable electrocatalyst toward hydrogen evolution reaction (HER) is important for the commercialization of water splitting technologies. The rational ...

Two-dimensional (2D) magnetic semiconductors feature both tightly-bound excitons with large oscillator strength and potentially long-lived coherent magnons due to the presence of bandgap and spatial confinement. While magnons and excitons are energetically mismatched by orders of magnitude, their coupling can lead to efficient optical access to spin information. Here we report strong magnon-exciton coupling in the 2D van der Waals (vdW) antiferromagnetic (AFM) semiconductor CrSBr. Coherent magnons launched by above-gap excitation modulate the interlayer hybridization, which leads to dynamic modulation of excitonic energies. Time-resolved exciton sensing reveals magnons that can coherently travel beyond 7 micrometer, with coherence time above 5 ns. We observe this exciton-coupled coherent magnons in both even and odd number of layers, with and without compensated magnetization, down to the bilayer limit. Given the versatility of vdW heterostructures, these coherent 2D magnons may be basis for optically accessible magnonics and quantum interconnects., 14 pages, 5 figures, 30 pages Supporting Info

We report the electrochemical performance and structural characteristics of porous nanostructured ceramic cathodes for thin-film solid oxide fuel cells (TF-SOFCs) based on yttria-stabilized zirconi...

Under the background of accelerating the process of power grid construction, the unified spatial-temporal data model of power grid resources has become a necessary means to describe the relationship between spatial objects and power grid data. Affected by the defect of the information island, some unified spatiotemporal data models of power grid resources have poor updating performance. Therefore, a unified spatiotemporal data model of power grid resources based on microservice architecture is designed. The architecture can obtain the spatial structure elements of the power grid area, identify the spatial correlation characteristics of the modeling object through the distribution of power energy supply lines, eliminate the dimension of meteorological data variables, design a unified resource scheduling scheme based on the microservice architecture, calculate the space-time weight matrix, and build a space-time data model. Test results are that under the two update task scenarios, the average update performance of the unified spatiotemporal data model of power grid resources based on the Internet of things is 11363 times/second. The average update performance of the unified spatiotemporal data model of power grid resources based on the Internet of things is 9958 times/second). And the average update performance of the unified spatiotemporal data model of power grid resources based on the genetic algorithm is 9771 times/second. It shows that the designed unified spatiotemporal data model of power grid resources is perfect after combining the microservice architecture.

Spin torque is a promising tool for driving magnetization dynamics for novel computing technologies. These torques can be easily produced by spin-orbit effects, but for most conventional spin source materials, a high degree of crystal symmetry limits the geometry of the spin torques produced. Magnetic ordering is one way to reduce the symmetry of a material and allow exotic torques, and antiferromagnets are particularly promising because they are robust against external fields. We present spin torque ferromagnetic resonance measurements and second harmonic Hall measurements characterizing the spin torques in antiferromagnetic iron rhodium alloy. We report extremely large, strongly temperature-dependent exotic spin torques with a geometry apparently defined by the magnetic ordering direction. We find the spin torque efficiency of iron rhodium to be (330$\pm$150) % at 170 K and (91$\pm$32) % at room temperature. We support our conclusions with theoretical calculations showing how the antiferromagnetic ordering in iron rhodium gives rise to such exotic torques., 21 pages, 6 figures

A high-performance solid oxide fuel cell (SOFC) stack technology is being developed, based on a design concept that incorporates prime-surface metallic interconnects with the versatility of stacking different types of single cells (sintered cells or metal-supported cells). A preliminary design of the prime-surface interconnect based on an egg-carton shape configuration has been advanced for this stack concept. Laboratory-scale prime-surface interconnects have successfully been fabricated by stamping and evaluated for mechanical loading, flow distribution and current collection properties. A process based on sputtering has been developed for fabricating supported thin-film (several micrometers thick) cells for this stack technology. Fabricated thin-film cells have shown desirable structural characteristics and exceptional performance on different fuels at reduced temperatures (550o-650oC). Sputtered cells (with yttria stabilized zirconia (YSZ) for the electrolyte, gadolinia-doped ceria (GDC) for the electrolyte/cathode interlayer, nickel-YSZ for the anode and lanthanum strontium cobalt iron perovskite (LSCF)–YSZ for the cathode) have exhibited peak power densities of ~1.7 W/cm2 and ~2.1 W/cm2 with hydrogen fuel and air at operating temperatures of 600oC and 650oC, respectively.

Thin film solid oxide fuel cells (TF-SOFCs) are attracting attention due to their ability to operate at comparatively lower temperatures (400-650 °C) that are unattainable for conventional anode-supported SOFCs (650-800 °C). However, limited cathode performance and cell scalability remain persistent issues. Here, we report a new approach of fabricating yttria-stabilized zirconia (YSZ)-based TF-SOFCs via a scalable magnetron sputtering process. Notable is the development and deposition of a porous La0.6Sr0.4Co0.2Fe0.8O2.95(LSCF)-based cathode with a unique fibrous nanostructure. This all-sputtered cell shows an open-circuit voltage of ∼1.0 V and peak power densities of ∼1.7 and ∼2.5 W/cm2 at 600 and 650 °C, respectively, under hydrogen fuel and air along with showing stable performance in short-term testing. The power densities obtained in this work are the highest among YSZ-based SOFCs at these low temperatures, which demonstrate the feasibility of fabricating exceptionally high-performance TF-SOFC cells with distinctive dense or porous nanostructures for each layer, as desired, by a sputtering process. This work illustrates a new, potentially low-cost, and scalable platform for the fabrication of next-generation TF-SOFCs with excellent power output and stability.

We report on the fabrication of nanoscale, three-terminal in-plane spin–orbit torque switching devices with low switching current densities. Critical parameters in the fabrication process, including the ion beam etching angle and time, were optimized to avoid fabrication defects and improve device yield. Measurements of the magnetic field and current-induced switching behavior of the tunnel junctions demonstrate a sensitivity to the nanopillar aspect ratio, which dictates the nanopillars’ anisotropy and thermal stability. Additionally, we show that the current density required for switching can be reduced and the device thermal stability increased by inserting Hf interlayers into the heterostructure. Micromagnetic simulations are generally consistent with the experimentally observed switching behavior, suggesting an increase in the interfacial perpendicular anisotropy at the CoFeB/MgO interface and the reduction in the Dzyaloshinskii–Moriya interaction at the W/CoFeB interface by the Hf interlayers.

MnZn ferrite powder particles were prepared via a sol–gel autocombustion method using nitrates as raw materials. Transmission electron micrographs revealed that the particles were uniform and decentralized with sizes of 20–30 nm. X-ray diffraction patterns showed characteristic features of Mn0.5Zn0.5Fe2O4 ferrite crystals with a nanocrystalline cubic spinel structure and crystallite size of 21.5 nm. The lattice constant determined from the Rietveld refinement was 8.475 A. A saturated magnetic induction intensity of 39.18 emu/g and coercive force of only 18.1 Oe were measured using a quantum design physical property measurement system.

In this work we explore the interplay of ferromagnetism and superconductivity of single-crystalline Ni nanowires measured with superconducting Nb leads.

A process based on sputtering has been developed for fabricating thin-film solid oxide fuel cells (TF-SOFCs) that have a total thickness of ~3 µm and are based on the conventional configuration using common SOFC materials. Single cells (with dense electrolytes, dense interlayers, and porous electrode films) on various substrates were effectively fabricated through sputtering/co-sputtering of metal and/or ceramic targets and the electrodes exhibited a fine nanostructure consisting of very small columns of roughly 10 nm in diameter. Fabricated cells exhibit open circuit voltages of ~1.0 V and exceptional power densities at reduced temperatures (500o-650oC) on different fuels. Single cells (of the composition lanthanum strontium cobaltite-gadolinium doped ceria (LSC-GDC) cathode/GDC interlayer/yttria stabilized zirconia (YSZ) electrolyte/Ni-GDC anode) show record power densities of ~3.5 W/cm2 with hydrogen/air and ~1.5 W/cm2 with dry methane/air at 650oC.

The personal ultraviolet (UV) dosimeter is a useful measurement tool to prevent UV induced dermal damages; however, conventional digital dosimeters are either bulky or require external power sources. Here, a wearable, colorimetric UV film dosimeter that provides color transition, from purple to transparent, is reported to indicate the UV dose. The film dosimeter is made of a purple photodegradable dye ((2Z,6Z)-2,6-bis(2-(2,6-diphenyl-4H-thiopyran-4-ylidene)ethylidene)cyclohexanone or DTEC) blended in low density polyethylene film. The DTEC film discolored 3.3 times more under the exposure of UV light (302 nm) than visible light (543 nm), and a UV bandpass filter is developed to increase this selectivity to UV light. The DTEC film completely discolors to transparency in 2 h under an AM 1.5 solar simulator, suggesting the potential as an indicator for individuals with types I-VI skin to predict interventions to avoid sunburn. Finally, the DTEC film is integrated with the UV bandpass filter on a wristband to function as a wearable dosimeter for low cost and convenient monitoring of sunlight exposure.