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The discovery of magnetism in ultrathin crystals opens up opportunities to explore new physics and to develop next-generation spintronic devices. Nevertheless, two-dimensional magnetic semiconductors with Curie temperatures higher than room temperature have rarely been reported. Ferrites with strongly correlated d -orbital electrons may be alternative candidates offering two-dimensional high-temperature magnetic ordering. This prospect is, however, hindered by their inherent three-dimensional bonded nature. Here, we develop a confined-van der Waals epitaxial approach to synthesizing air-stable semiconducting cobalt ferrite nanosheets with thickness down to one unit cell using a facile chemical vapor deposition process. The hard magnetic behavior and magnetic domain evolution are demonstrated by means of vibrating sample magnetometry, magnetic force microscopy and magneto-optical Kerr effect measurements, which shows high Curie temperature above 390 K and strong dimensionality effect. The addition of room-temperature magnetic semiconductors to two-dimensional material family provides possibilities for numerous novel applications in computing, sensing and information storage. Van der Waals crystals allow for magnetism down to the monolayer limit, however, this magnetism, and frequently the material itself, is fragile. Ferrites, conversely, have robust material stability and magnetic order, but are three dimensional. Here the authors succeed in creating a single unit cell thickness of Cobalt Ferrite via chemical vapour deposition, with hard magnetic properties, and curie temperature exceeding room temperature.

Black phosphorus (BP), a fascinating semiconductor with high mobility and a tunable direct bandgap, has emerged as a candidate beyond traditional silicon-based devices for next-generation electronics and optoelectronics. The ability to grow large-scale, high-quality BP films is a prerequisite for scalable integrated applications but has thus far remained a challenge due to unmanageable nucleation events. Here we develop a sustained feedstock release strategy to achieve subcentimetre-size single-crystal BP films by facilitating the lateral growth mode under a low nucleation rate. The as-grown single-crystal BP films exhibit high crystal quality, which brings excellent field-effect electrical properties and observation of pronounced Shubnikov–de Haas oscillations, with high mobilities up to ~6,500 cm2 V−1 s−1 at low temperatures. We further extend this approach to the growth of single-crystal BP alloy films, which broaden the infrared emission regime of BP from 3.7 μm to 6.9 μm at room temperature. This work will greatly facilitate the development of high-performance electronics and optoelectronics based on BP family materials.Subcentimetre-size black phosphorous and its alloy films have been achieved on conventional substrates through sustained feedstock release design, and exhibit high crystalline quality and composition-dependent bandgap tunability.

Defects play a crucial role in determining electric transport properties of two-dimensional transition metal dichalcogenides. In particular, defect-induced deep traps have been demonstrated to possess the ability to capture carriers. However, due to their poor stability and controllability, most studies focus on eliminating this trap effect, and little consideration was devoted to the applications of their inherent capabilities on electronics. Here, we report the realization of robust trap effect, which can capture carriers and store them steadily, in two-dimensional MoS 2x Se 2(1-x) via synergistic effect of sulphur vacancies and isoelectronic selenium atoms. As a result, infrared detection with very high photoresponsivity (2.4 × 10 5  A W −1 ) and photoswitching ratio (~10 8 ), as well as nonvolatile infrared memory with high program/erase ratio (~10 8 ) and fast switching time, are achieved just based on an individual flake. This demonstration of defect engineering opens up an avenue for achieving high-performance infrared detector and memory. Utilization of inevitable defect states in 2D materials can enable efficient photodetection and memory applications. Here, the authors report use of defect-induced deep traps to capture and store carriers in exfoliated flakes of MoS 2x Se 2(1-x) as photodetectors with high responsivity of 2.4 × 10 5 A/W at 1550 nm and non-volatile memories with photo-switching ratio of 10 8 .

Two-dimensional (2D) transition metal dichalcogenides (TMDs) with fascinating electronic energy band structures, rich valley physical properties and strong spin-orbit coupling have attracted tremendous interest, and show great potential in electronic, optoelectronic, spintronic and valleytronic fields. Stacking 2D TMDs have provided unprecedented opportunities for constructing artificial functional structures. Due to the low cost, high yield and industrial compatibility, chemical vapor deposition (CVD) is regarded as one of the most promising growth strategies to obtain high-quality and large-area 2D TMDs and heterostructures. Here, state-of-the-art strategies for preparing TMDs details of growth control and related heterostructures construction via CVD method are reviewed and discussed, including wafer-scale synthesis, phase transition, doping, alloy and stacking engineering. Meanwhile, recent progress on the application of multi-functional devices is highlighted based on 2D TMDs. Finally, challenges and prospects are proposed for the practical device applications of 2D TMDs.

Two-dimensional materials are of interest for the development of electronic devices due to their useful properties and compatibility with silicon-based technology. Van der Waals heterostructures, in which two-dimensional materials are stacked on top of each other, allow different materials and properties to be combined and for multifunctional devices to be created. Here we show that an asymmetric van der Waals heterostructure device, which is composed of graphene, hexagonal boron nitride, molybdenum disulfide and molybdenum ditelluride, can function as a high-performance diode, transistor, photodetector and programmable rectifier. Due to the asymmetric structure of the device, charge-carrier injection can be switched between tunnelling and thermal activation under negative and positive bias conditions, respectively. As a result, the device exhibits a high current on/off ratio of 6 × 10 8 and a rectifying ratio of ~10 8 . The device can also function as a programmable rectifier with stable retention and continuously tunable memory states, as well as a high program/erase current ratio of ~10 9 and a rectification ratio of ~10 7 . An asymmetric van der Waals heterostructure device, which is composed of graphene, hexagonal boron nitride, molybdenum disulfide and molybdenum ditelluride, can function as a high-performance diode, transistor, photodetector and programmable rectifier.

Van der Waals multiferroic structures hold promises for advancing the development of low-power multifunctional nanoelectronics devices, but single-phase two-dimensional multiferroic materials are limited. In this study, we constructed a room-temperature P(VDF-TrFE)/Fe 3 GaTe 2 heterostructure (ferromagnetic layer thickness of 4.8 nm). and demonstrate significant bidirectional modulation of the Curie temperature upon application of ±90 V. Specifically, the Curie temperature decreased from 326 K to 247 K under +90 V and increased to 366 K under −90 V. Notably, we observed layer-dependent magnetic modulation, In 3-layer Fe 3 GaTe 2 , transitioning from negative to positive polarization increases Curie temperature, while thicker configurations show a decrease. This phenomenon originates from the competition between interlayer/intralayer magnetic exchange coupling driven by the electric field (density functional theory calculations), supporting non-volatile switching of the magnetization state, which is suitable for high-precision neural network computing. This discovery provides an innovative approach for developing low-power multifunctional nanoelectronics devices using two-dimensional magnetoelectric coupling structures. The authors construct a room-temperature multiferroic heterostructure system based on P(VDFTrFE)/Fe3GaTe2, achieving a reversible electrically regulated transition between the ferromagnetic and paramagnetic states.

In the post-Moore era, CMOS technology faces challenges in storage and power consumption. Two-dimensional van der Waals ferromagnets, with their atomically sharp interfaces, enable heterostructure with ferroelectric materials. Through strong magnetoelectric coupling effects, they provide an ideal platform for developing highly efficient magnetoelectric interfaces. Leveraging this ideal platform, this study proposes a strain-modulation strategy based on vertically integrated two-dimensional van der Waals multiferroic heterojunctions Fe 3 GaTe 2 /P(VDF-TrFE) to address these challenges. This structure utilizes the inverse piezoelectric effect of ferroelectric polymers to induce strain. Through magnetoelectric coupling, the heterojunction achieves non-volatile reconfiguration of the magnetic anisotropy constant of Fe 3 GaTe 2 at room temperature. This enables fully reversible electrical control of the anomalous Hall resistance and inverter functionality. Device integration validated reconfigurable logic gates and half-adder circuits, demonstrating ultra-low energy consumption (0.5 aJ), nanosecond-scale write speeds (5 ns), and high operational stability. Two-dimensional van der Waals ferromagnetic materials can achieve efficient integration with ferroelectric materials. The authors propose a strain-modulation strategy based on multiferroic heterostructure Fe 3 GaTe 2 /P(VDF-TrFE) to achieve low power operation.

Magnetic 2D materials have gotten significant attention due to their unique low‐dimensional magnetism and potential applications in advanced spintronics, providing an perfect platform for investigating magnetic properties at the 2D limit. The chemical vapor deposition (CVD), known for its simplicity and strong controllability, has become a key technique for fabricating ultrathin magnetic nanosheets. This article systematically reviews recent advancements in CVD‐grown magnetic 2D materials, focusing on the effects of growth parameters on material morphologies and properties, and analyzing the construction of heterostructures and their role in magnetic regulation. In addition, various magnetic characterization methods are introduced, and potential applications of these materials in spintronic devices are discussed. By summarizing current challenges, the article provides insights into future research directions, emphasizing the need to improve material stability, Curie temperature, and scalable synthesis to enable practical applications of 2D magnetic materials. Magnetic 2D materials have gotten significant attention due to their unique low‐dimensional magnetism and potential applications in spintronics. This review summarizes and analyzes the key factors and control strategies in the CVD growth of 2D magnetic materials. Additionally, it provides an overview of commonly used magnetic characterization techniques and applications of 2D magnetic materials in spintronic devices.

Barriers that charge carriers experience while injecting into channels play a crucial role on determining the device properties of van der Waals semiconductors (vdWS). Among various strategies to control these barriers, inserting a graphene layer underneath bulk metal may be a promising choice, which is still lacking experimental verification. Here, it is demonstrated that graphene/metal hybrid structures can form quasi‐van der Waals contacts (q‐vdWC) to ambipolar vdWS, combining the advantages of individual metal and graphene contacts together. A new analysis model is adopted to define the barriers and to extract the barrier heights in ambipolar vdWS. The devices with q‐vdWC show significantly reduced Schottky barrier heights and thermionic field emission activation energies, ability of screening the influence from substrate, and Fermi level unpinning effect. Furthermore, phototransistors with these special contacts exhibit enhanced performances. The proposed graphene/metal q‐vdWC may be an effective strategy to approach the Schottky–Mott limit for vdWS. Quasi‐van der Waals contacts (q‐vdWC) to ambipolar van der Waals semiconductors (vdWS) combine the advantages of individual metal and graphene contacts together. An analysis model is adopted to extract the barrier heights in ambipolar vdWS. The devices with q‐vdWC show significantly reduced SBH and Ea, ability of screening the influence from substrate, Fermi level unpinning effect, and enhanced photoelectrical performances.

The downscaling of complementary metal-oxide-semiconductor technology has produced breakthroughs in electronics, but more extreme scaling has hit a wall of device performance degradation. One key challenge is the development of insulators with high dielectric constant, wide bandgap and high tunnel masses. Here, we show that two-dimensional monocrystalline gadolinium pentoxide, which is devised through combining particle swarm optimization algorithm and theoretical calculations and synthesized via van der Waals epitaxy, could exhibit a high dielectric constant of ~25.5 and a wide bandgap simultaneously. A desirable equivalent oxide thickness down to 1 nm with an ultralow leakage current of ~10 −4  A cm −2 even at 5 MV cm −1 is achieved. The molybdenum disulfide transistors gated by gadolinium pentoxide exhibit high on/off ratios over 10 8 and near-Boltzmann-limit subthreshold swing at an operation voltage of 0.5 V. We also constructed inverter circuits with high gain and nanowatt power consumption. This reliable approach to integrating ultrathin monocrystalline insulators paves the way to future nanoelectronics. Two-dimensional monocrystalline gadolinium pentoxide with high dielectric constant and wide bandgap was prepared through van der Waals epitaxy, allowing the realization of sub-1 nm equivalent oxide thickness and low-power nanoelectronics.