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This study presents an intelligent soft robotic system capable of perceiving, describing, and sorting objects based on their physical properties. This work introduces a bimodal self‐powered flexible sensor (BSFS) based on the triboelectric nanogenerator and giant magnetoelastic effect. The BSFS features a simplified structure comprising a magnetoelastic conductive film and a packaged liquid metal coil. The BSFS can precisely detect and distinguish touchless and tactile models, with a response time of 10 ms. By seamlessly integrating the BSFSs into the soft fingers, this study realizes an anthropomorphic soft robotic hand with remarkable multimodal perception capabilities. The touchless signals provide valuable insights into object shape and material composition, while the tactile signals offer precise information regarding surface roughness. Utilizing a convolutional neural network (CNN), this study integrates all sensing information, resulting in an intelligent soft robotic system that accurately describes objects based on their physical properties, including materials, surface roughness, and shapes, with an accuracy rate of up to 97%. This study may lay a robotic foundation for the hardware of the general artificial intelligence with capacities to interpret and interact with the physical world, which also serves as an interface between artificial intelligence and soft robots. [ABSTRACT FROM AUTHOR]

Rich functionalities have been identified for domain walls (DWs, naturally occurring interfaces in ferroics), e.g., enhanced conductance and photovoltaic effect, which specify the interest in their internal structure. The dimension/width and type are of particular interest, which is the carrier of their functionality. Recent attention has been focused on head‐to‐head or tail‐to‐tail charged DWs with greatly enhanced conductivity compared to the inner domains, which are found to be an order of magnitude thicker (tens of unit cells) than normal neutral DWs. In this study, ultrathin non‐Ising charged DWs are found, where polarization switched their direction within 2–3 unit cells in self‐assembled BiFeO3 nanocrystals. An analytical model and finite element method simulation are used to interpret the origin of this phenomenon, i.e., electrostatic constraints linked to DW configurations in a ferroelectric. This study indicates that as an intrinsic property, the width of the ferroic DWs varies with different electrostatic constraints and must be taken into consideration during its applications. [ABSTRACT FROM AUTHOR]

Nonmetal heteroatom incorporation into the lattice of host materials is a common way to regulate the surface electronic structure of electrocatalysts to boost their electrocatalytic performance. However, the heteroatom incorporation will inevitably trigger lattice strain and vacancy, which may lead to large changes in the structure of host materials. In this situation, the reconstruction of doped catalysts easily occurs during the catalytic process under harsh alkaline media, which hinders understanding the structure–activity correlation between catalysts and catalytic performance. Herein, taking cobalt nitride as an example, it is promulgated that a low‐temperature selenium sublimation strategy can effectively optimize the surface electronic structure in Co4N nanowire arrays with no significant change of bulk phase structure. Benefiting from surface selenium modification, the optimized SeCo4N nanowire arrays exhibit a 6.5 times enhancement of catalytic activity with structural phase stability for hydrogen evolution reaction in basic media. These findings may provide a new concept to design stable structured catalysts for energy‐related applications. [ABSTRACT FROM AUTHOR]

Interfacially asymmetric magnetic multilayers made of heavy metal/ferromagnet have attracted considerable attention in the spintronics community for accommodating spin‐orbit torques (SOTs) and meanwhile for hosting chiral spin textures. In these multilayers, the accompanied interfacial Dzyaloshinskii–Moriya interaction (iDMI) permits the formation of Néel‐type spin textures. While significant progresses have been made in Co, CoFeB, Co2FeAl, CoFeGd based multilayers, it would be intriguing to identify new magnetic multilayers that could enable spin‐torque controllability and meanwhile host nanoscale skyrmions. In this report, first, thin films made of permanent magnet SmCo5 with perpendicular magnetic anisotropy are synthesized, in which the deterministic SOT switching, enabled by the spin Hall effect, in Pt/SmCo5/Ta trilayer is demonstrated. Further, the stabilization of room‐temperature skyrmions with diameters ≈100 nm in [Pt/SmCo5/Ta]15, together with a skyrmionium‐like spin texture in [Pt/SmCo5/Ir]15 multilayers is shown. Based on the material specific parameters, micromagnetic simulations are also carried out. The results confirm the presence of chiral spin textures in this new material family. Through interfacial engineering, the results thus demonstrate that rare earth permanent magnets could be a new platform for studying interfacial chiral spintronics. [ABSTRACT FROM AUTHOR]

Ever‐increasing demand on electronic devices with ultrahigh‐density non‐volatile data storage has attracted great interest in novel ferroelectric memories based on conductive ferroelectric domain walls. Embedded in an insulating material, ferroelectric domain walls have the capability of being (re)created, displaced, erased, and altered in their spatial configurations and electronic characteristics. However, the domain wall conductivities are in most cases not yet sufficiently high to ensure the current density required to drive read‐out circuits operating at high speeds. In this work, a giant domain wall current (>10 µA) of a single charged domain wall is obtained through conductive atomic force microscopy with a bias field of 4 V. This is achieved in self‐assembled BiFeO3 nanocrystals grown by sol‐gel method on Nb‐doped SrTiO3 substrates. Local configurations of domains and domain wall types are studied using vector piezoresponse force microscopy and high‐resolution transmission electronic microscopy. The enhancement of the wall current is shown to be due to the formation of conducting pathways of charged defects accumulated along domain walls and traversing the nanocrystals. The diverse domain walls can be manipulated by electric field in a perpendicular architecture. The perpendicular array structure of BiFeO3 nanocrystals should have great potentials for developing perpendicular nanoelectronic prototypes. [ABSTRACT FROM AUTHOR]

In article number 1808376, Cheng Song, Feng Pan, and co‐workers report a high‐performance two‐terminal selector based on a symmetrical multilayer structure of homogeneous tantalum oxides, possessing bidirectional threshold switching operation, large selectivity, high compliance currents, and tunable threshold voltages. The selector can realize 1S1R read‐write functions, thus avoiding crosstalk issues, and is stacked with a memristor. The design might advance practical implementation of two‐terminal selectors in the field of emerging memories and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Two‐terminal selectors with high nonlinearity, based on bidirectional threshold switching (TS) behaviors, are considered as a crucial element of crossbar integration for emerging nonvolatile memory and neuromorphic network. Although great efforts have been made to obtain various selectors, existing selectors cannot fully satisfy the rigorous standard of assorted memristive elements and it is in great demand to enhance the performance. Here, a new type of Ag/TaOx/TaOy/TaOx/Ag (x < y) selector based on homogeneous trilayered oxides is developed to attain the required parameters including bidirectional TS operation, a large selectivity of ≈1010, a high compliance current up to 1 mA, and ultralow switching voltages under 0.2 V. Tunable operation voltages can be realized by modulating the thickness of inserted TaOy. All‐TaOx‐based integrated 1S1R (one selector and one memristor) cells, prepared completely by magnetron sputtering and no need of a middle electrode, exhibit a nonlinear feature, which is quite characteristic for the crossbar devices, avoiding undesired crosstalk current issues. The tantalum‐oxide‐based homojunctions offer high insulation, low ion mobility, and rich interfaces, which is responsible for the modulation of Ag conductive filaments and corresponding high‐performance cation‐based selector. These findings might advance practical implementation of two‐terminal selectors in emerging memories, especially resistive random access memories. A high‐performance two‐terminal selector based on a symmetrical multilayer design is developed, possessing bidirectional threshold switching operations, a large selectivity of ≈1010, a high compliance current up to 1 mA, and tunable threshold voltages. Stacked with a memristor, the selector can realize 1S1R (one‐selector‐one‐memristor) function, avoiding crosstalk issues. A reasonable hourglass model is proposed to interpret the underlying mechanism. [ABSTRACT FROM AUTHOR]