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Incipient ferroelectricity bridges traditional dielectrics and true ferroelectrics, enabling advanced electronic and memory devices. Firstly, we report incipient ferroelectricity in freestanding SrTiO3 nanomembranes integrated with monolayer MoS2 to create multifunctional devices, demonstrating stable ferroelectric order at low temperatures for cryogenic memory devices. Our observation includes ultra-fast polarization switching (~10 ns), low switching voltage (<6 V), over 10 years of nonvolatile retention, 100,000 endurance cycles, and 32 conductance states (5-bit memory) in SrTiO3-gated MoS2 transistors at 15 K and up to 100 K. Additionally, we exploit room-temperature weak polarization switching, a feature of incipient ferroelectricity, to construct a physical reservoir for pattern recognition. Our results showcase the potential of utilizing perovskite material properties enabled by advancements in freestanding film growth and heterogeneous integration, for diverse functional applications. Notably, the low 180 °C thermal budget for fabricating the 3D-SrTiO3/2D-MoS2 device stack enables the integration of diverse materials into silicon complementary metal-oxide-semiconductor technology, addressing challenges in compute-in-memory and neuromorphic applications. Sen et al. report the stacking of a perovskite incipient ferroelectric nanomembrane with atomically thin 2D material for a back-end-of-line compatible ferroelectric-like field effect transistors, functioning as a cryogenic memory at 15 K and as an inference engine at room temperature. [ABSTRACT FROM AUTHOR]

Nanoribbons (NRs) of atomic layer transition metal dichalcogenides (TMDs) can boost the rapidly emerging field of quantum materials owing to their width-dependent phases and electronic properties. However, the controllable downscaling of width by direct growth and the underlying mechanism remain elusive. Here, we demonstrate the vapor-liquid-solid growth of single crystal of single layer NRs of a series of TMDs (MeX2: Me = Mo, W; X = S, Se) under chalcogen vapor atmosphere, seeded by pre-deposited and respective transition metal-alloyed nanoparticles that also control the NR width. We find linear dependence of growth rate on supersaturation, known as a criterion for continues growth mechanism, which decreases with decreasing of NR width driven by the Gibbs-Thomson effect. The NRs show width-dependent photoluminescence and strain-induced quantum emission signatures with up to ≈ 90% purity of single photons. We propose the path and underlying mechanism for width-controllable growth of TMD NRs for applications in quantum optoelectronics.Size control in quantum materials by direct growth is still difficult to achieve. Here, the authors present the width-dependent growth of single-layer nanoribbons of transition metal dichalcogenides from nanoalloy seeds, achieving strain-induced quantum emission with a purity of up to 90 % for single photons. [ABSTRACT FROM AUTHOR]

Electrocatalysis has received a great deal of interest in recent decades as a possible energy‐conversion technology involving a variety of chemical processes. External magnetic field application is a powerful method for improving electrocatalytic performance that is customizable and compatible with existing electrocatalytic devices. In addition, magnetic fields can assist in catalyst synthesis and act on the catalytic reaction process. This paper systematically reviews the most recent developments in magnetic field‐assisted electrocatalytic enhancement technology. The enhancement of electrocatalysis by a magnetic field is mainly represented in the three features listed below: The spin selectivity effect improves the activity of the catalyst in a magnetic field; furthermore, magnetic fields can improve mass transport and electron transport in catalytic processes (due to Lorentz forces, Kelvin forces, magnetohydrodynamic [MHD], and micro‐MHD); the magnetothermal effect may raise the reaction temperature and boost electrocatalytic activity. This review focuses on the rational design of catalytic systems incorporating the interaction between catalysts and magnetic fields, aiming to produce enhanced catalytic effects. The recommendations for further utilization of strategies for electrocatalysis and broader energy technologies for magnetic fields, as well as potential challenges for future research, are also discussed. [ABSTRACT FROM AUTHOR]

Ion implantation is widely used for doping semiconductors or electroceramic materials and probing material behaviors in extreme radiation environments. However, implanted ions can induce compressive stresses into the host material, which can induce plasticity and mesoscopic deformation. However, these phenomena have almost exclusively been observed in brittle ionic and/or covalently bonded materials. Here, we present transmission electron microscopy observations of unusual implantation-induced plasticity in two metallic alloys. First, Fe2+ ions induce dislocation plasticity below the implanted layer in a model Fe-P alloy. Next, He+ ions form pressurized cavities which activate the fcc-to-hcp strain-induced martensitic transformation in Alloy 625. In both cases, the plasticity can be explained by a combination of implanted ions being incorporated into the lattice and the creation of irradiation defects. These findings have significant implications for mechanical testing of ion-implanted layers, while also opening pathways for using ion implantation to tune stress distributions in metallic alloys. [ABSTRACT FROM AUTHOR]

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Electrochemical properties of the graphite electrode in potassium-ion batteries (KIBs) depend on the selection of the proper binder. The results in our experiment show that compared with the conventional binders of poly(vinylidene fluoride) (PVDF) and carboxymethylcellulose sodium (CMCNa), the polyacrylate sodium (PAANa) binder can greatly improve the electrochemical performance during the potassiation and depotassiation. Specifically, the initial discharge and charge capacity of the graphite-PAANa electrode are 415.4 and 238.5 mAh g−1, respectively. Even after 50 cycles, it still has a high charge capacity retention of 96.9%. Considering the good swelling property of the PAANa binder, the adhesive and mechanical strength of composite electrodes are obviously enhanced. In addition, the graphite-PAANa electrode can also decrease the electrolyte decomposition on the graphite particle surface and restrain the capacity fading resulted from the repeatedly volume expansion. [ABSTRACT FROM AUTHOR]

Although the insertion of potassium ions into graphite has been proven to be realistic, the electrochemical performance of potassium‐ion batteries (PIBs) is not yet satisfactory. Therefore, more effort is required to improve the specific capabilities and achieve a long cycling life. The mild carbonization process in molten salt (NaCl‐KCl) is used to synthesize nitrogen/oxygen co‐doped hierarchically porous carbon (NOPC) for PIBs by using cyanobacteria as the carbon source. This exhibits highly reversible capacities and ultra‐long cycling stability, retaining a capacity of 266 mA h g−1 at 50 mA g−1 (100 cycles) and presents a capacity of 104.3 mA h g−1 at 1000 mA g−1 (1000 cycles). Kinetics analysis reveals that the potassium ion (K+) storage of NOPC is controlled by a capacitive process, which plays a crucial role in the excellent rate performance and superior reversible ability. The high proportion of capacitive behavior can be ascribed to the hierarchically porous structure and improved conductivity resulting from nitrogen and oxygen doping. Furthermore, density functional theory (DFT) calculations theoretically validate the enhanced potassium storage effect of the as‐obtained NOPC. More importantly, the route to NOPC from cyanobacteria in molten salt provides a green approach to the synthesis of porous carbon materials. [ABSTRACT FROM AUTHOR]

Sn‐based materials, one of the most promising alternatives, hold higher theoretical capacity (994 mA h g−1) than traditional graphite anodes and attract great attention in lithium‐ion batteries (LIBs). In this work, an in‐situ formed sodium chloride (NaCl) is employed as the template to support the formation of a three‐dimensional (3D) hierarchical porous carbon skeleton. The 3D porous materials, which specific surface area reach 221.1 m2/g, can shorten the ions transport path and increase the contact between the electrode and the electrolyte. Meanwhile, the Sn nanoparticles are restricted in the carbon matrix, which can effectively enhance the conductivity and solve some major problems of the volume fluctuation, particle aggregation and electrode pulverization. Consequently, the 3D porous carbon skeleton/Sn (3D‐PCSS) composites exhibit a high capacity (1046.7 mA h g−1 at 50 mA g−1 after 60 cycles), long cycle life (490 mA h g−1 after 600 cycles at 1000 mA g−1) and excellent rate performance. Moreover, a new method to improve energy storage properties in LIBs will be involved‐confining Sn nanoparticles in hierarchically porous 3D carbon skeleton. Sn nanoparticles anchored on 3D porous carbon skeleton (3D‐PCSS) was prepared by an in‐situ formed NaCl template‐assisted synthesis approach. 3D porous carbon skeleton provided the electron pathway and offered stable mechanical support against the volume variation of Sn particles and promoting electron and ion transfer and accelerating electrochemical reaction. [ABSTRACT FROM AUTHOR]

Advanced nanostructured functional materials obtained from the precursors of metal–organic frameworks show several unique advantages, including plentiful porous structures and large specific surface areas. Based on this, designed and constructed are highly dispersed ZnSe nanoparticles anchored in a N‐doped porous carbon rhombic dodecahedron (ZnSe@NDPC) by a sequential high‐temperature pyrolysis and selenization method. The specific synthesis process involves a two‐step heat treatment of the template‐engaged reaction between zinc‐based zeolitic imidazolate framework (ZIF‐8) and selenium power. By optimizing the calcination temperature, the as‐synthesized ZnSe@NDPC‐700 as an advanced anode of potassium ion batteries demonstrates the best electrochemical performance, including a high capacity (262.8 mA h g−1 over 200 cycles at 100 mA g−1) and a good rate capability (109.4 mA h g−1 at 2000 mA g−1 and 52.8 mA h g−1 at 5000 mA g−1). Moreover, the capacitance and diffusion mechanisms are also investigated by the qualitative and quantitate analysis, finally accounting for the superior K storage. [ABSTRACT FROM AUTHOR]