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In this study, Al-doped CuO–ZnO composite revealed a huge dielectric constant and fast adsorption–photocatalytic properties for industrial Congo red, Reactive yellow 145 and methyl green pollutants. Nanocrystalline ZnO, CuO and Al-doped CuO–ZnO composite was synthesized via sol–gel method. The X-ray diffraction analysis verified that the composite structure has hexagonal ZnO and monoclinic CuO phases. The morphological study of Al-doped CuO–ZnO composite displayed different types of particles having hexagonal, sheet and very fine shapes. Optically, Al-doped CuO–ZnO composite has a high visible light absorption ability compared to its individual components. For energy storage, Al-doped CuO–ZnO composite showed a semi-stable giant dielectric constant with value of 7.6215 × 104 at 42 Hz. Furthermore, Al-doped CuO–ZnO composite exhibited a remarkable adsorption of Congo red, Reactive yellow 145 and methyl green dyes in addition to fast photocatalytic characteristics under sunlight. Herein, 75 mg of Al-doped CuO–ZnO composite exhibits adsorption capacity of 54, 49 and 45% for 100 mL solution contains 20 mg/L Congo red, reactive yellow 145 and methyl green, respectively. As well, the photocatalytic measurements under sunlight confirmed the full removal of all dyes after 20–25 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core–shell CdS/ZnS nanorod co-doped with MoS 2 were fabricated by three step process. • The 7 mol% MoS 2 co-doped CdS/ZnS heterostructure showed maximum H 2 evaluation of 13,589 μmol h-1g−1. • The optimal sample showed 19 and 158 times higher H 2 evolution than individual metal sulfides. • CdS/ZnS co-doped with MoS 2 nanorods demonstrated good chemical stability. Hydrogen generation via semiconductor photocatalysts has gained significant attention as a sustainable fuel generation process. To demonstrate the performance of nanoscale core–shell heterostructure in photocatalytic hydrogen production, we have fabricated CdS nanorods coated with ZnS photocatalyst via wet-chemical reaction followed by deposition of ultrathin MoS 2 nanosheets by photo reduction process. The effect of ZnS content and suitable amount of MoS 2 loading over the visible-light induced photocatalytic hydrogen evolution was examined in Na 2 S and Na 2 SO 3 aqueous solutions. Interestingly, it is apparent that a close connection (or heterojunction) between CdS and ZnS is believed to easily tunnel the charge carriers to the surplus surface states, making its electrons and holes energetically favourable to transfer from ZnS to MoS 2 for photocatalytic reactions and subsequently, enhances the H 2 evolution activity in CdS/ZnS type I core–shell heterostructures. The optimal MoS 2 concentration is resolved to be 7 mol% and the subsequent visible-light induced H 2 generation rate was 13589 μmol h−1g−1, which is 19 and 158 fold higher than pristine CdS and ZnS respectively. The probable photocatalytic mechanism of CdS/ZnS type I core–shell heterostructure with MoS 2 cocatalyst is proposed. Our inexpensive and convenient preparation strategy may offer novel prospects in the engineering of desirable nanoheterostructures with better performance. [ABSTRACT FROM AUTHOR]

In this study, the geometric and electronic properties of Ti2CO2 and Ti2CO2/G heterostructures as anode materials for sodium-ion batteries were systematically investigated using first-principles calculations. The storage mechanism and properties of sodium atoms on Ti2CO2 and Ti2CO2/G heterostructures were further studied. By comparing the adsorption energy (− 1.4 eV, − 1.26 eV), diffusion barrier (0.21 eV, 0.14 eV), storage capacity (478mAh/g, 528mAh/g), average open-circuit voltage (0.68 eV, 0.51 eV), and elastic modulus (161.40 N/m, 364.82 N/m) of sodium atoms on Ti2CO2 and Ti2CO2/G heterostructures, we found that Ti2CO2/G heterostructure exhibits superior structural stability, better electronic conductivity, higher storage capacity, lower average open-circuit voltage, lower diffusion barrier, and superior mechanical performance. Through this study, we explore the potential of Ti2CO2/G as an anode material for sodium-ion batteries and its sodium storage mechanism. [ABSTRACT FROM AUTHOR]

Recently, the assembly of van der Waals heterostructures (vdWH) has proved to be an effective strategy to alter the properties and enhance the functionality of multifunctional devices based on 2D materials. Herein, first‐principles calculations are employed to construct the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH, exploring its electronic properties, contact characteristics, and the impact of electric gating. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH is predicted to be structurally, thermally, and mechanically stable. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH leads to a reduction in the bandgap compared to the constituent components, potentially enhancing optical absorption. Furthermore, the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure forms the type‐II band alignment, localizing electrons and holes predominantly in the HfS2${\rm HfS}_2$ and MoS2${\rm MoS}_2$ layers, respectively. Such type‐II HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure makes it promising candidate for the optoelectronic devices, benefiting from the spatial separation of photogenerated electron‐hole pairs. Notably, the electronic properties and contact characteristics of the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH are controllable under electric gating. The negative electric gating facilitates to a transformation from type‐II to type‐I band alignment, while the positive electric field induces a shift from semiconductor to metal in the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH. This findings can provide valuable insights into the fundamental aspects that contribute to the exceptional performance observed in HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH toward high‐performance multifunctional devices. [ABSTRACT FROM AUTHOR]

Converting transverse photons into longitudinal two-dimensional plasmon-–polaritons (2D-PP) and vice versa presents a significant challenge within the fields of photonics and plasmonics. Therefore, understanding the mechanism which increases the photon – 2D-PP conversion efficiency could significantly contribute to those efforts. In this study, we theoretically examine how efficiently incident radiation, when scattered by a silver spherical nanoparticle (Ag-NP), can be transformed into 2D-PP within van der Waals (vdW) heterostructures composed of hexagonal boron nitride and graphene (hBN/Gr composites). We show that the Dirac plasmon (DP) excitation efficiency depends on the Ag-NP radius as R3, and decreases exponentially with Ag-NP height h, so that for a certain Ag-NP geometry up to 25 % of the incident electrical field is channeled into the DP. We demonstrate that the linear plasmons (LPs) excitation efficiency can be manipulated by changing the graphene–graphene distance Δ (or hBN thickness) or by changing the number of graphene layers N. By increasing Δ and/or N the LPs move towards smaller wave vectors Q and become accessible by the Ag-NP dipole field, so that for N ≥ 5 the excitation of more than one LP is possible. These results are supported by recent scattering-type scanning near-field optical microscopy (s-SNOM) measurements. Furthermore, we show that Ag-NPs with specific parameters preferentially hybridizes with DPs of a particular wavelength λD, facilitating selective excitation of DPs. The obtained tuning possibilities could have a significant impact on applied plasmonics, photonics or optoelectronics. [ABSTRACT FROM AUTHOR]

Tailoring the morphological features of nanomaterials is of great importance for varied applications in energy storage, environment remediation etc. but is hampered by different parameters. Herein, a novel step by step synthesis approach is reported to elucidate different morphology of MoS2 heterostructures. A solvothermal method is employed to synthesize molybdenum glycerate (MoG) solid spheres (SS) followed by subsequent sulphidation. Continuous sulphidation of 3 hours and 8 hours produces flowers and ball-in-ball MoS2 heterostructures respectively. FESEM micrographs show the formation of MoG SS and different MoS2 heterostructures. XRD, Raman and UV measurements confirm the phase transition from 2H (semiconductor) to 1T (metallic) phase in 8 hours sulphidated ball-in-ball heterostructure. The formation of ball-in-ball morphology is attributed to the Kirkendall effect. The findings could potentially be extended to the idea of phase transitions and their applications. [ABSTRACT FROM AUTHOR]

Hybrid nanocomposites integrating nanostructured zinc oxide (ZnO) and carbon quantum dots (CQDs) with designed heterostructures possess exceptional optical and electronic properties. These properties hold immense potential for advancements across diverse scientific and technological fields. This review article investigates the synthesis, properties, and applications of ZnO‐CQD heterostructure nanocomposites. Recent breakthroughs in fabrication methods are examined, including hydrothermal, microwave‐assisted, and eco‐friendly techniques. Key preparation methods such as sol‐gel, co‐precipitation, and electrochemical deposition are discussed, emphasizing their role in controlling heterostructure formation. This review analyses the impact of heterostructures on optical and electronic properties, such as fluorescence, photoluminescence, and photocatalytic activity. Synergistic interactions between ZnO and CQDs within heterostructures are highlighted, demonstrating how they lead to substantial performance improvements. Applications of ZnO‐CQD heterostructures span solar cells, LEDs, photodetectors, water purification, antimicrobial treatments, gas sensing, catalysis, biomedical imaging, drug delivery, environmental sensing, and energy storage. Insights are provided into refining synthesis methods, enhancing characterisation techniques, and broadening the application landscape. Challenges like stability are addressed, along with strategies for optimised performance and practical implementation. This comprehensive review offers a thorough understanding of ZnO‐CQD heterostructure nanocomposites, emphasising their significance within materials science and engineering. By addressing core concepts and future directions, it lays a foundation for continued innovation in this dynamic field. [ABSTRACT FROM AUTHOR]

Flexible electronics has emerged as a continuously growing field of study. Two‐dimensional (2D) materials often act as conductors and electrodes in electronic devices, holding significant promise in the design of high‐performance, flexible electronics. Numerous studies have focused on harnessing the potential of these materials for the development of such devices. However, to date, the incorporation of 2D materials in flexible electronics has rarely been summarized or reviewed. Consequently, there is an urgent need to develop comprehensive reviews for rapid updates on this evolving landscape. This review covers progress in complex material architectures based on 2D materials, including interfaces, heterostructures, and 2D/polymer composites. Additionally, it explores flexible and wearable energy storage and conversion, display and touch technologies, and biomedical applications, together with integrated design solutions. Although the pursuit of high‐performance and high‐sensitivity instruments remains a primary objective, the integrated design of flexible electronics with 2D materials also warrants consideration. By combining multiple functionalities into a singular device, augmented by machine learning and algorithms, we can potentially surpass the performance of existing wearable technologies. Finally, we briefly discuss the future trajectory of this burgeoning field. This review discusses the recent advancements in flexible sensors made from 2D materials and their applications in integrated architecture and device design. [ABSTRACT FROM AUTHOR]

GaN-based enhancement-mode high-electron-mobility transistors (HEMTs) with a 25-nm-thick undoped GaN (u-GaN) cap underneath the gate metallization on ultrathin-barrier (UTB) AlGaN (<6 nm)/GaN heterostructures have been demonstrated. The presence of a thick u-GaN cap contributes to the increased depletion of the two-dimensional electron gas (2DEG) beneath the gate by polarization effects, resulting in an improvement of the threshold voltage (Vth) and a suppression of the off-state gate leakage (Ioff). The UTB HEMTs with a thick u-GaN cap exhibit normally-off operation with a Vth of 0.5 V, a maximum on-current of 232.1 mA/mm, an Ioff of 10−6 mA/mm, and a gate voltage swing of 7 V at a drain bias of 10 V. Thanks to the p-doping-free GaN cap, the device demonstrates excellent Vth stability under positive gate bias, which positions it as a promising candidate for future low-voltage GaN power applications. [ABSTRACT FROM AUTHOR]

MnWO4/WO3 p-n heterojunction films were fabricated using a one-step method consisting of the plasma electrolytic oxidation (PEO) of titanium in homogeneous electrolytes containing paratungstate ions and stable watersoluble EDTA-chelated manganese. The influences of the formation current density and W:Mn molar ratio of the electrolyte, which was varied from 1:2 to 2:1, on the composition, morphology, and optical and photocatalytic properties of the resulting coatings were studied. X-ray diffraction analysis, scanning electron microscopy, energy dispersive X-ray analysis, Raman spectroscopy, and ultraviolet diffuse reflectance spectroscopy were used to characterize the formed composites. Regardless of the W:Mn ratio of the electrolyte, the coatings contained crystalline t-WO3 and m-MnWO4. Depending on the formation conditions, the optical band gap energies of the composites varied from 2.63 to 3.01 eV. The largest absorption red shift and lowest band gap energy were observed in the film composite formed in an electrolyte with W:Mn = 2:1, at a current density of 0.2 A cm-2. Composites obtained in electrolytes with W:Mn ratios of 2:1 and 1:1 exhibited photocatalytic activity in the degradation of rhodamine C and methyl orange dyes in the presence of 10 mmol L-1 H2O2 under ultraviolet and visible light irradiation. The role of hydrogen peroxide in this dye degradation on PEO-coated composites under light irradiation is discussed. [ABSTRACT FROM AUTHOR]

To achieve the rapid and real-time detection of triethylamine (TEA) gas, this study synthesized a gas sensor based on heterostructures of Fe2O3/MoO3 using a hydrothermal method. Fe2O3/MoO3 composites with a narrow bandgap (1.1 eV) were successfully synthesized by constructing heterostructures. The rapid and efficient detection of triethylamine was achieved at 220 °C. The response and response/recovery times of the Fe2O3/MoO3 sensor with 50 x 10-6 triethylamine were 132s and 5s/10s, respectively. The Fe2O3/MoO3 sensor maintained a good response to triethylamine gas, even at 80% relative humidity. The sensing mechanism of the Fe2O3/MoO3 sensor can be described in terms of adsorption energy and electronic behavior of the sensing layer using density functional theory (DFT). The results are consistent with the excellent selectivity and rapid response/recovery of the Fe2O3/MoO3 gas sensor for triethylamine. Therefore, the construction of heterostructures to facilitate electron transmission is an effective strategy to achieve rapid detection of triethylamine and is worthy of further exploration and investigation. [ABSTRACT FROM AUTHOR]

Material-by-design has been a long-standing aspiration that has recently become a reality. Such designer materials have been repeatedly demonstrated using the top-down approach of mechanical exfoliation and stacking, leading to a variety of artificial 2D heterostructures with new properties that are otherwise unattainable. Consequently, tremendous research frontiers in physics, chemistry, engineering, and life science have been created. While thousands of layered crystals exist in nature, only a few dozen of them with manageable chemical-stability have been made into heterostructures using this method. Moreover, experimental investigations of materials that have received limited exploration in the 2D realm, such as cuprates, halides, and perovskites, along with their heterostructures, have been fundamentally hindered by their rapid chemical degradation. Another critical challenge imposed by exfoliating and stacking 2D layers in ambient environment is the absorption of itinerant gas molecules that further contaminate sensitive 2D interfaces in the heterostructures. Such contamination and compromised material properties significantly hinder surface-sensitive local probes—scanning probe microscopy (SPM)—that often require nanometer to atomic scale surface cleanliness. In this article, we aim to provide a technical review of recent development toward 2D materials and heterostructure fabrication in more controlled environments that are suitable for SPM characterizations. These include the development of more efficient mechanical exfoliation and dry-transfer techniques, as well as the incorporation of 2D material exfoliation and transfer in inert gas, low vacuum, and, eventually, ultra-high vacuum environments. Finally, we provide an outlook on the remaining challenges and opportunities in ultra-clean 2D material fabrication techniques. [ABSTRACT FROM AUTHOR]

This study defines the technological procedures for obtaining GexSi1 – x alloys through the diffusion method by introducing germanium atoms into monocrystalline silicon. The research results indicate that the fundamental parameters of the resultingGexSi1 – x alloys differ from the fundamental parameters of the initial silicon, particularly altering the energy values of silicon's forbidden zone. Elemental analysis of the sample surfaces revealed silicon concentration (in atomic percentages) of approximately ~ 70.66 % and germanium ~29.36%. To manufacture and study the parameters of silicon-based solar cells with GexSi1 – x–Si heterostructures, we used samples obtained by two different methods. In the first method, the p-n junction was formed by introducing phosphorus impurity atoms into the original silicon of p-type silicon grade. In the second method, the p-n junction was formed by boron diffusion into the original silicon of SEPH (silicon electronic type, doping material of phosphorus) grade. In both cases, the depth of the p-n junction ranged from 0.5 to 6 μm. It was also shown that the binary compounds GexSi1 – x are a new material for modern electronics; the possibility of creating properties in electronics based on them was shown. Based on them, it is proposed to create devices and new functionality and highly efficient solar cells. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) anisotropic materials have garnered significant attention in the realm of anisotropic optoelectronic devices due to their remarkable electrical, optical, thermal, and mechanical properties. While extensive research has delved into the optical and electrical characteristics of these materials, there remains a need for further exploration to identify novel materials and structures capable of fulfilling device requirements under various conditions. Here, we employ heterojunction interface engineering with black phosphorus (BP) to disrupt the C3 rotational symmetry of monolayer WS2. The resulting WS2/BP heterostructure exhibits pronounced anisotropy in exciton emissions, with a measured anisotropic ratio of 1.84 for neutral excitons. Through a comprehensive analysis of magnetic-field-dependent and temperature-evolution photoluminescence spectra, we discern varying trends in the polarization ratio, notably observing a substantial anisotropy ratio of 1.94 at a temperature of 1.6 K and a magnetic field of 9 T. This dynamic behavior is attributed to the susceptibility of the WS2/BP heterostructure interface strain to fluctuations in magnetic fields and temperatures. These findings provide valuable insights into the design of anisotropic optoelectronic devices capable of adaptation to a range of magnetic fields and temperatures, thereby advancing the frontier of material-driven device engineering. [ABSTRACT FROM AUTHOR]

Highlights: The interfacing between SnO2 and MXene alters electronic structures, shifting the d-band center in transition metals, enhancing catalytic efficiency by reducing electron filling in antibonding orbitals. A binder-free, ultrathin, laminar heterostructured interlayer on polypropylene separator is demonstrated. The ionic sieving mechanism and efficient adsorption–catalysis process enable deeper charge/discharge cycle and improved stability. The improved catalytic conversion and suppressed lithium dendrites formation enable a high loading of 7.5 mg cm−2 and an initial area capacity of 7.6 mAh cm−2. Poor cycling stability in lithium–sulfur (Li–S) batteries necessitates advanced electrode/electrolyte design and innovative interlayer architectures. Heterogeneous catalysis has emerged as a promising approach, leveraging the adsorption and catalytic performance on lithium polysulfides (LiPSs) to inhibit LiPSs shuttling and improve redox kinetics. In this study, we report an ultrathin and laminar SnO2@MXene heterostructure interlayer (SnO2@MX), where SnO2 quantum dots (QDs) are uniformly distributed across the MXene layer. The combined structure of SnO2 QDs and MXene, along with the creation of numerous active boundary sites with coordination electron environments, plays a critical role in manipulating the catalytic kinetics of sulfur species. The Li–S cell with the SnO2@MX-modified separator not only demonstrates superior electrochemical performance compared to cells with a bare separator but also induces homogeneous Li deposition during cycling. As a result, an areal capacity of 7.6 mAh cm−2 under a sulfur loading of 7.5 mg cm−2 and a high stability over 500 cycles are achieved. Our work demonstrates a feasible strategy of utilizing a laminar separator interlayer for advanced Li–S batteries awaiting commercialization and may shed light on the understanding of heterostructure catalysis with enhanced reaction kinetics. [ABSTRACT FROM AUTHOR]

Spintronic devices that utilize spin transfer torque are promising for integrated memory applications. However, these devices face substantial energy consumption challenges due to the high current densities required for switching. Conversely, voltage‐driven spintronic devices, using capacitive displacement charge, can realize switching operations that are energy‐efficient (≈1–10 fJ bit−1). This work investigates switching based on voltage control of the interlayer exchange coupling in perpendicular magnetic anisotropy (PMA) multilayered heterostructures. Unlike previous works that utilized gating techniques that employ ionic transport mechanisms to control interlayer exchange coupling, this study employs electrostatic gating by using MgO, which is more compatible with modern spintronic‐based memories. These results suggest that the magnetization anisotropy, and the magnitude, and phase of the Ruderman‐Kittel‐Kasuya‐Yosida (RKKY) coupling function with spacer layer thickness can be controlled through electric gating, providing a promising avenue for the development of energy‐efficient magnetic data storage devices. [ABSTRACT FROM AUTHOR]

Over the last years metal halide perovskites have demonstrated remarkable potential for integration in light emitting devices. Heterostructures allow for tunable bandgap depending on the local anion composition, crucial for optoelectronic devices, but local structural effects of anion exchange in single crystals is not fully understood. Here, we investigate how the anion exchange of CsPbBr3 nanowires fully and locally exposed to HCl vapor affects the local crystal structure, using nanofocused x-rays. We study the nanoscale composition and crystal structure as function of HCl exposure time and demonstrate the correlation of anion exchange with changes in the lattice parameter. The local composition was measured by x-ray fluorescence and x-ray diffraction, with general agreement of both methods but with much less variation using latter. The heterostructured nanowires exhibit unintentional gradients in composition, both axially and radially. Ferroelastic domains are observed for all HCl exposure times, and the magnitude of the lattice tilt at the domain walls scales with the Cl concentration. [ABSTRACT FROM AUTHOR]

The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb2O5 thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb2O5 with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb2O5 compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb2O5 exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb2O5 make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb2O5 are 0.28 S/mWcm−2 and 1.68 × 1011 Jones respectively. The sensor response towards NO2 gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb2O5 exhibits high selectivity towards the NO2 gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb2O5. The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life. [ABSTRACT FROM AUTHOR]

Remote sensing technology, which conventionally employs spectrometers to capture hyperspectral images, allowing for the classification and unmixing based on the reflectance spectrum, has been extensively applied in diverse fields, including environmental monitoring, land resource management, and agriculture. However, miniaturization of remote sensing systems remains a challenge due to the complicated and dispersive optical components of spectrometers. Here, m‐phase GaTe0.5Se0.5 with wide‐spectral photoresponses (250–1064 nm) and stack it with WSe2 are utilizes to construct a two‐dimensional van der Waals heterojunction (2D‐vdWH), enabling the design of a gate‐tunable wide‐spectral photodetector. By utilizing the multi‐photoresponses under varying gate voltages, high accuracy recognition can be achieved aided by deep learning algorithms without the original hyperspectral reflectance data. The proof‐of‐concept device, featuring dozens of tunable gate voltages, achieves an average classification accuracy of 87.00% on 6 prevalent hyperspectral datasets, which is competitive with the accuracy of 250–1000 nm hyperspectral data (88.72%) and far superior to the accuracy of non‐tunable photoresponse (71.17%). Artificially designed gate‐tunable wide‐spectral 2D‐vdWHs GaTe0.5Se0.5/WSe2‐based photodetector present a promising pathway for the development of miniaturized and cost‐effective remote sensing classification technology. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures have gained significant attention in photodetectors due to their seamless integration with materials possessing diverse functionalities. In this study, the fabrication of a Te nanomesh/black‐Si vdW heterostructure is presented, and investigated its photoresponse properties. The heterostructure exhibits a pronounced rectification behavior, characterized by a rectification ratio of 2.2 × 104. Notably, the heterostructure device demonstrates commendable photoresponse properties, including a high responsivity of 350 mA W−1, an extensive linear dynamic range of 45.5 dB, a high specific detectivity of 9.6 × 1011 Jones, and a wide spectral response ranging from 400 to 1550 nm. Furthermore, the heterostructure exhibits rapid response, with a rise time and a decay time of 70 and 140 µs, respectively. These exceptional photoresponse properties can be attributed to the robust internal built‐in electrical field at the hetero‐interface and the augmented light absorption in black‐Si. The outstanding photoresponse properties of the heterostructure make it a promising candidate for multiwavelength single‐pixel imaging, enabling the collection of mask patterns under varying wavelengths of light radiation. This work provides a novel approach for fabricating mixed‐dimensional vdW heterostructures, offering promising prospects for advancements in optoelectronics. [ABSTRACT FROM AUTHOR]

Neuromorphic visual systems based on optogenetic techniques have colossal potential for in‐memory computing with prospects of developing artificial intelligence vision systems. However, conventional transistor architectures face formidable challenges in efficient signal processing owing to limitations in the intrinsic properties of active channel materials. In this work, a novel transition metal telluride‐sulfide hybrid heterojunction‐based optoelectronic synaptic phototransistor is proposed, in which UV–vis responsive zinc oxide encapsulated few‐layer tungsten disulfide channel is decorated with near‐infrared sensitive 0D cobalt ditelluride (CoTe2) nanocrystals (NCs), eliciting the ability to sense, store, and process optical signals across a broad range of the electromagnetic spectrum. This meticulously designed three‐layered heterostructure, based on their interfacial band alignments, enables high photoresponsivity up to ≈2.6 × 103 A W−1 at a back‐gate bias of 20 V, leading to the brain‐inspired synaptic applications with an average power consumption as low as 75 pJ for each training process. The device exhibits excitatory postsynaptic current, paired‐pulse facilitation with an index above 150%, as well as light‐modulated synaptic plasticity by mimicking biological synapses, which mainly originate from trapped holes in Co‐vacancy mediated surface defect states of CoTe2 NCs. Hence, this 2D material‐based hybrid phototransistor appears to be a promising candidate for energy‐efficient next‐generation brain‐inspired neuromorphic vision systems. [ABSTRACT FROM AUTHOR]

The fabrication of van der Waals heterostructures (vdWHs) has drawn considerable interest because of their wide range of functionalities. Herein, a novel PdSe2/ReSe2 vdWHs with gate‐tunable rectification behavior and excellent broadband photodetection characteristics is presented. The application of the gate bias substantially enhances the rectification behavior, with the highest rectification ratio (≈3.13 × 103) observed at gate voltage Vg = −60 V. The density functional theory calculations demonstrate the direct and indirect bandgap behavior of PdSe2 and ReSe2 in the monolayer structure, respectively. Additionally, the PdSe2/ReSe2 heterojunction displays a strong photo‐response in the near‐infrared region and achieves a high photoresponsivity, an excellent external quantum efficiency, and rapid rise and decay times of 1.7 × 103 A W−1, 4.05 × 103, and 5 and 20 ms, respectively. Furthermore, the device exhibits a remarkable detectivity of ≈3.5 × 1012 Jones. The findings hold great potential for advancing the fabrication of multifunctional vdW heterostructure devices. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures, formed by stacking different two‐dimensional (2D) materials, have emerged as a promising platform for next‐generation optoelectronic devices through band engineering. While various all‐2D and mixed‐dimensional heterojunction phototransistors based on p–n junctions or Schottky junctions have been developed, their performance, often constrained by the trade‐off between responsivity (R) and response speed, limits their widespread application. Here, a dual‐mode phototransistor based on a MoTe2/WS2/WSe2 double vdW heterostructure is designed. The bottom WSe2 layer effectively modulates the entire MoTe2/WS2 heterojunction channel, enabling both photoconductive and photovoltaic modes with exceptional optoelectronic properties in a single device. Specifically, the proposed device exhibits a maximum R of 2540 A W−1 and an impressive specific detectivity of 8 × 1012 Jones under the photoconductive mode. Under the photovoltaic mode, it achieves a fast response speed of 35.3/49.1 µs and a high light on/off ratio of 2 × 105. Additionally, the device exhibits latent potential for high‐resolution imaging across various wavelengths and fast optical communication. This work offers a rational alternative for achieving dual‐mode photodetection and highlights its promising application prospects in imaging and optical communication. [ABSTRACT FROM AUTHOR]

In-plane heterostructures based on transition metal dichalcogenides are promising for applications in tunnel field-effect transistors (TFETs). However, the transport properties of the in-plane heterostructures have not been fully understood due to the presence of generation current derived from the in-gap state of the heterointerface. For further performance improvement, it is important to identify and suppress the origin of the in-gap states at the heterointerface. In this work, we investigated the transport properties of TFETs based on multilayer NbxMo1−xS2/MoS2 in-plane heterostructures on atomically flat hexagonal boron nitride substrate. We observed a transition from staggered gap to broken gap band alignment by electron doping to MoS2 and that band-to-band tunneling current was dominant below 80 K, a higher temperature compared with the heterostructure on an SiO2 surface. These results indicate that the use of atomically flat substrates helps reduce generation current from strain-derived in-gap states in NbxMo1−xS2/MoS2 in-plane heterostructures. [ABSTRACT FROM AUTHOR]

We performed spin-torque ferromagnetic resonance studies on the Al/NiFe/AlOx heterostructure. We observed a large non-trivial field-like torque, τ FL z , due to the out-of-plane spin polarization, despite the lack of heavy metal in our multilayer. The torque conductivity is found to be significant with a value equal to σ FL z = (21 ± 2) ℏ 2 e × 10 3 Ω − 1 m − 1 . From a detailed Al thickness dependence, we show that τ FL z arises from the interface between Al and NiFe. We demonstrate that the observed τ FL z arises from the spin-swapping mechanism at the Al/NiFe interface rather than the orbital Hall effect of Al. This observation of a non-trivial spin–orbit torque in the low-cost light element, Al, is highly significant for the energy-efficient control of spintronic devices. [ABSTRACT FROM AUTHOR]

We report the observation of unidirectional magnetoresistance (UMR) in the ferrimagnetic insulator CoFe2O4(CFO)/Pt heterostructures, which stem from the giant interfacial Rashba–Edelstein effect. Furthermore, UMR has been found to show sign reversal and amplitude enhancement characteristics with decrease in temperature. We have ascribed it to the modulated distortion of Fermi contours due to pronounced spin canting at low temperatures. The presence of spin canting induced interfacial magnetic state has also been demonstrated by spin Hall magnetoresistance in CFO/Pt/Co/Al2O3 films. Our work reveals the interfacial magnetic state modulated UMR in CFO/Pt bilayers, thereby paving the way for extending its applications in ferrimagnet-based spintronic devices. [ABSTRACT FROM AUTHOR]

Magnetoresistance (MR) of two-dimensional hole gas (2DHG) samples fabricated from GaN/AlxGa1-xN/GaN (x = 0.2–0.25) double heterostructures has been investigated to reveal subband electronic parameters and low field spin splitting properties. In sample with high sheet hole density (ps ≤ 1.3 × 1013/cm2), 2DHG occupies two subbands, while in samples with low ps (≤0.3 × 1013/cm2), only one subband is occupied. In both samples, the low-field spin–orbit coupling constant α of 2DHG was obtained independently from the weak anti-localization data and the fast Fourier transform analysis of MR oscillations. The results yield a constant α ∼ 0.53–6.1 × 10−12 eVm and a spin splitting ΔE = 2αkf ∼ 0.6–6.0 meV. These results strongly depend on the hole mass value, but appear to be of the same order as the results for 2D electron gas in similar material systems and structures. [ABSTRACT FROM AUTHOR]

The integration of complex oxides with a wide range of functionalities on conventional semiconductor platforms is highly demanded for functional applications. Despite continuous efforts to integrate complex oxides on Si, it is still challenging to harvest epitaxial layers using standard deposition processes. Here, a novel method is demonstrated to create high‐quality complex heterostructures on Si integrated with SrTiO3 membranes as a universal platform. The STO membrane successfully bridges a broad spectrum of complex heterostructures such as SrNbO3, SrVO3, TiO2, and dichalcogenide 2D superconducting FeSe toward semiconducting wafers (Si). Through electronic structures measured by angle‐resolved photoemission spectroscopy, the high quality and functionality of the heterostructures are verified. This study demonstrated a new pathway toward realizing electronic devices with multifunctional physical properties incorporated into Si. [ABSTRACT FROM AUTHOR]

The bulk photovoltaic effect (BPVE) originating from spontaneous charge polarizations can reach high conversion efficiency exceeding the Shockley-Queisser limit. Emerging van der Waals (vdW) heterostructures provide the ideal platform for BPVE due to interfacial interactions naturally breaking the crystal symmetries of the individual constituents and thus inducing charge polarizations. Here, we show an approach to obtain ultrafast BPVE by taking advantage of dual interfacial polarizations in vdW heterostructures. While the in-plane polarization gives rise to the BPVE in the overlayer, the charge carrier transfer assisted by the out-of-plane polarization further accelerates the interlayer electronic transport and enhances the BPVE. We illustrate the concept in MoS2/black phosphorus heterostructures, where the experimentally observed intrinsic BPVE response time achieves 26 ps, orders of magnitude faster than that of conventional non-centrosymmetric materials. Moreover, the heterostructure device possesses an extrinsic response time of approximately 2.2 ns and a bulk photovoltaic coefficient of 0.6 V−1, which is among the highest values for vdW BPV devices reported so far. Our study thus points to an effective way of designing ultrafast BPVE for high-speed photodetection. The bulk photovoltaic effect (BPVE) has potential for the realization of high conversion efficiency optoelectronic devices. Here, the authors show that combined in-plane and out-of-plane charge polarizations in MoS2/black phosphorus heterostructures can enhance the BPVE and reduce the extrinsic response times down to 2.2 ns. [ABSTRACT FROM AUTHOR]

In this work, the influence of two-dimensional state density on oscillations of transverse electrical conductivity in heterostructures with rectangular quantum wells is investigated. A new analytical expression is derived for calculating the temperature dependence of the transverse electrical conductivity oscillation and the magnetoresistance of a quantum well. For the first time, a mechanism has been developed for oscillating the transverse electrical conductivity and magnetoresistance of a quantum well from the first-order derivative of the magnetic field (differential) ∂ (ρ ⊥ 2 d (E , B , T , d)) ∂ B at low temperatures and weak magnetic fields. The oscillations of electrical conductivity and magnetoresistance of a narrow-band quantum well with a nonparabolic dispersion law are investigated. The proposed theory investigated the results of experiments of a narrow-band quantum well (InxGa 1 − x Sb). [ABSTRACT FROM AUTHOR]

Schottky junction barrier is promising to suppress dark current in photodetectors by blocking the tunneling electrons. Due to the Fermi pinning effect, designing the Schottky barrier with a conventional 3D metal/2D semiconductor interface is challenging. Here, it is shown that a 2D semimetal‐semiconductor van der Waals Schottky junction can be utilized to design the near‐ideal Schottky barrier for the high Ion/Ioff ratio photodetectors. It is demonstrated that the experimental barrier height (≈467 meV) of the 1T′‐MoTe2/WS2 Schottky junction can largely follow the Schottky‐Mott rule by effectively resolving the Fermi pinning effect. Such increased barrier height suppresses the thermionic emission (TE) and the tunneling of the electrons. However, for the photo‐generated electron‐hole pairs with the higher energy case, holes cannot be prevented, while most of the electrons with the higher energy can also be easily transferred. The 1T′‐MoTe2/WS2/1T′‐MoTe2 photodetector exhibits the dark current density of 5 × 10−13 A µm−1, a light on/off ratio of 106, a responsivity of 30 A W−1, and a detectivity of 1.82 × 1014 Jones. Modulated Schottky barrier height is adopted to construct a self‐powered 1T′‐MoTe2/WS2/Au photodetector. [ABSTRACT FROM AUTHOR]

Transition‐metal dichalcogenide (TMD) monolayers are direct‐gap semiconductors with peculiar spin–valley coupling. Combining two different TMDs can lead to a type‐II band alignment and formation of interlayer excitons (ILE). In MoSe2–WSe2 heterobilayers, optically bright ILE are only observable if the interlayer twist angle is close to 0° (aligned, R‐type) or 60° (anti‐aligned, H‐type). Herein, low‐temperature optical spectroscopy studies of these ILE in high magnetic fields are presented. Depending on interlayer twist, ILE transitions are either valley conserving or between different valleys. This allows engineering of the ILE g factor, changing its magnitude and even its sign. Additionally, applied magnetic fields induce a valley polarization of the ILE, and its buildup can directly be observed in helicity‐ and time‐resolved photoluminescence, with peculiar features due to the dependence of ILE optical selection rules on interlayer registry. For both, R‐type and H‐type structures, it is found that at 24 Tesla, the valley polarization is resonantly enhanced, even though their g factors are markedly different. This observation hints at a scattering process involving single carriers within the ILE and zone‐boundary acoustic phonons. [ABSTRACT FROM AUTHOR]

To design and construct bifunctional electrocatalyst with high activity is important to the commercial development of electrochemical water splitting (EWS) technology. The carbon clothe (CC) supported on Ni(OH) 2 nanosheet is used as template to tune the morphology of Ni 0.85 Se. To improve the activity of Ni 0.85 Se, amorphous Ni 4 Mo alloy is anchored on the Ni 0.85 Se to obtain the Ni 0.85 Se/Ni 4 Mo catalyst (NS/NM) by electrodeposition method. The electron state and conductivity of NS/NM are modulated compared to that of the NS sample. It is found that the electron transfers from Ni 4 Mo to Ni 0.85 Se. Benefiting from the tuned electron state of Ni 0.85 Se and Ni 4 Mo, the enhanced number of exposed active sites and lower R ct value, the NS/NM heterostructure electrode requires low overpotentials of 51 and 206 mV to obtain 10 mA cm−2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The optimized electrode shows fast kinetics and exhibits near to 100% Faraday efficiency for HER and OER in 1 M KOH. Importantly, it is noted that the electrocatalytic activity of NS/NM catalyst for both HER and OER is enhanced obviously in comparison with NS sample. With heterostructure catalyst, the EWS only proceeds at 1.48 V to yield 10 mA cm−2, which is reduced about 110 mV compared to NS electrode. Here, a novel kind of bifunctional heterostructure electrocatalyst is constructed. [Display omitted] • The heterostructure of crystalline Ni 0.85 Se anchored on amorphous Ni 4 Mo alloys was prepared. • The formation of heterostructure causes the redistribution of electrons. • The introduction of Ni 4 Mo enhances the activity for HER and OER obviously. • With heterostructure catalyst, the EWS only proceeds at 1.48 V to yield 10 mA cm−2. [ABSTRACT FROM AUTHOR]

In the realm of sustainable and environmentally friendly "green-hydrogen" fuel demand, water electrolysis stands as a pathway of hope for the extraction of renewable hydrogen. However, the durability and efficiency of electrocatalysts have been a major challenge in this process, owing to factors like the high costs of noble catalysts (Pt, Ir, Ru, etc.) and their limited stability. Layered Nickel-iron double hydroxides (NiFe-LDH) have shown potential as low-cost and efficient electrocatalysts because of their suitable electronic configuration and distinguished orbital confinement. However, their durability In the realm of sustainable and environmentally friendly "green-hydrogen" fuel demand, water electrolysis stands as a pathway of hope for the extraction of renewable hydrogen. However, the durability and efficiency of electrocatalysts have been a major challenge in this process, owing to factors like the high costs of noble catalysts (Pt, Ir, Ru, etc.) and their limited stability. Layered Nickel-iron double hydroxides (NiFe-LDH) have shown potential as low-cost and efficient electrocatalysts because of their suitable electronic configuration and distinguished orbital confinement. However, their performance and durability in corrosive alkaline water at high current density remain limited. In this regard, one can make the nano-composites of this NiFe-LDH with high electronic conductivity materials and layered structures like VSe 2. With this motivation, this work presents a novel electrocatalyst, NiFe-LDH, supported with VSe 2 nanosheets ( V Se 2 / NiFe − LDH), designed to address these challenges and enhance water splitting efficiency. Experimental results demonstrate that the heterostructure synergistically reduces charge transfer resistance, increases exposure of active sites, and enhances oxygen gas evolution ability. Consequently, the V Se 2 / NiFe − LDH electrocatalyst demonstrated superior sustainability, maintaining an elevated current density (500 mA cm − 2 ) for over 50 h of continuous electrolysis without noticeable degradation. This research opens up new possibilities and shows that nano-compositing can be a good option for achieving efficient and durable electrocatalysts in alkaline water splitting, thereby contributing to sustainable hydrogen production. [Display omitted] • Facile hydro/solvothermal preparation of composites of NiFe-LDH and VSe 2. • Enhanced Oxygen and Hydrogen evolution were observed. • Decreased charge transfer resistance was noticed. • Durable up to about 50 h for overall water splitting at a high current density of 500 mA cm − 2. [ABSTRACT FROM AUTHOR]

Highlights: Reduced graphene oxide/carbon foams (RGO/CFs) vdWs heterostructures are efficiently fabricated via a simple mixed-dimensional assembly strategy. Linkage effect of optimized impedance matching and enhanced dielectric loss abilities endows the excellent microwave absorption performances of RGO/CFs vdWs heterostructures. Multiple functions such as good corrosion resistance performances and outstanding thermal insulation capabilities can be integrated into RGO/CFs vdWs heterostructures. Considering the serious electromagnetic wave (EMW) pollution problems and complex application condition, there is a pressing need to amalgamate multiple functionalities within a single substance. However, the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges. Herein, reduced graphene oxide/carbon foams (RGO/CFs) with two-dimensional/three-dimensional (2D/3D) van der Waals (vdWs) heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying, immersing absorption, secondary freeze-drying, followed by carbonization treatment. Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching, the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances, achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of − 50.58 dB with the low matching thicknesses. Furthermore, the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties, good corrosion resistance performances as well as outstanding thermal insulation capabilities, displaying the great potential in complex and variable environments. Accordingly, this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures, but also outlined a powerful mixed-dimensional assembly strategy for engineering multifunctional foams for electromagnetic protection, aerospace and other complex conditions. [ABSTRACT FROM AUTHOR]

Properties of ferroelectric semiconductors have garnered significant research interest, particularly due to their non-volatile memory. Meanwhile, studies on the characteristics of two-dimensional (2D) ferroelectrics have appeared as a crucial topic in solar cells, i.e., bulk photovoltaic effects. In this work, we propose two heterostructures: Cs2PbI2Cl2/Sc2CO2-UP (CSUP) and Cs2PbI2Cl2/Sc2CO2-DOWN (CSDN) for solar cells, to examine their photoelectric properties by using first-principles. Our findings indicate that such two heterostructures may have both high exciton binding energies and strong optical absorption coefficients in the ultraviolet region, with the CSDN showing exceptional carrier mobility as well. Moreover, we explore their characteristics by means of modulations of electric fields and stresses. The results reveal that the transition of band alignment in the CSUP can be engineered from type-II to type-I under the control of the electric fields, which may significantly increase the power conversion efficiency in actual solar cells. Moreover, both may have good potential in the application of logic devices. All these outputs may imply that, by means of fine modulations on photoelectric properties, the Cs2PbI2Cl2/Sc2CO2 possess immense potential to become multifunctional devices in ultraviolet photodetectors, solar cells, and logic devices. [ABSTRACT FROM AUTHOR]

We show that the interplay between spin–orbit coupling (SOC) and the paramagnetic response of itinerant electrons in proximitized superconductor/paramagnet systems gives rise to the inverse spin galvanic effect, i.e., generation of magnetic moment under the influence of the charge current. Depending on the sign of the SOC constant and the system temperature, the corresponding contribution to the magnetic response of the superconductor can be either diamagnetic or paramagnetic. We discuss the relevance between the discovered phenomena and the recent experiments on Pt/Nb heterostructures as well as the puzzling sign change of the magnetic response observed in clean Ag coated Nb cylinders. [ABSTRACT FROM AUTHOR]

Resourceful and inexpensive seawater direct splitting omits the desalination process and effectively increases the efficiency of hydrogen energy generation. However, the development of seawater splitting is hampered by the competing selectivity challenges from anodic oxygen evolution reaction (OER) and chlorine evolution reaction and the issues of electrode corrosion. Herein, the borate anion‐intercalated NiV‐LDH nanoflakes/NiCoP nanowires heterostructures supported on Ni foam (2D/1D NiV‐BLDH/NiCoP/NF) is synthesized. Theoretical calculations show that a small amount of V atom doping in Ni(OH)2 is favorable for changing the electronic environment around Ni atoms via bridging Ni─O, which can construct Ni─O─V to accelerate electron transfer and promote catalytic activity. The borate anions (B(OH)4−) intercalation not only results in the good hydrophilicity and high OH− selectivity but also weakens the adsorption of chlorine (Cl−), which effectively restrains the chlorine evolution reaction. Thus, the component optimized NiV0.1‐BLDH/NiCoP/NF electrocatalyst only requires 268 mV overpotential to reach 100 mA cm−2 for OER in an alkaline environment. Particularly, the NiCoP/NF||NiV0.1‐BLDH/NiCoP/NF cell exhibits attractive overall water splitting performance with a low voltage of 1.46 and 1.53 V at 10 mA cm−2 in alkaline freshwater and alkaline seawater, respectively. The design strategy of this electrocatalyst provides a new avenue for seawater splitting. [ABSTRACT FROM AUTHOR]

Organic single crystals with near‐infrared (NIR) emission demonstrate their excellent optical communications from well photonic confinement and low optical waveguide loss, which are considered as competitive candidates toward advanced optoelectronics. However, the increasingly diverse and sophisticated application demands result in the complicated design of NIR devices, which is hardly realized solely by the intrinsic properties of individual crystals. Herein, a programmable assembly strategy is presented to fabricate organic heterostructures. Triphenylene (TP), pyrene (Py) and 7,7,8,8‐tetracyanoquinodimethane (TCNQ) are primary selected to prepared organic cocrystals with narrow band gap and near‐infrared emission. Importantly, the charge‐transfer alloy with tunable emission from 700 nm to 850 nm and branched heterostructures with multichannel characteristics are prepared from these organic cocrystals by following the growth kinetics process at molecular level and lattice matching principle at structural level, respectively. Theses prepared heterostructures exhibit optical logic operation capabilities, which can serve as optical modulators. This work provides new insights into the manufacturing of organic NIR heterostructures applied in advanced optoelectronics. [ABSTRACT FROM AUTHOR]

Research on two-dimensional (2D) materials has made tremendous progress reflecting their unique properties and promising applications. In this perspective, we review the novel concept of "2.5-dimensional (2.5D) materials", which represent new opportunities to extend the field of materials science beyond 2D materials. This concept consists of controlling van der Waals interactions and using interlayer nanospaces to synthesize new materials and explore their intriguing properties. It also includes combination with other dimensional materials, the fabrication of three-dimensional (3D) architectures of 2D materials, and practical applications in our 3D everyday life. We discuss recent research based on this concept and provide future perspectives. Although atomically thin 2D materials have attracted great interest from their unique properties and promising applications, the integration of multiple 2D materials or their modifications are more exciting because they offer opportunities to explore new frontier of materials science. This perspective illustrates the new concept of "2.5-dimensional (2.5D) materials", which symbolically represents the great potential offered by different routes to extend the realm of 2D materials. Some examples of 2.5D materials are reviewed, such as multicomponent heterostructures, intercalation, combination with other dimensional materials, functionalization, and application to 3D devices. In this perspective, we present the recent progress of this 2.5D materials research and future outlook. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) is a 2D material with excellent electrical and optical properties, and developing a universal technology for the preparation of high‐performance MoS2‐based photodetector is extremely desirable. Here, a UV to NIR broadband flexible photodetector based on MoS2/(PDPP3T) inorganic–organic hybrid heterostructures is reported. In the experiment, high crystalline 2H‐phase few‐layer MoS2 nanoflakes are first prepared by optimized electrochemical intercalation of tetraheptylammonium cation (THA+) and ultrasound‐assisted exfoliation strategy. Thereafter, a narrow bandgap organic semiconductor PDPP3T is introduced to construct the MoS2/Poly(diketopyrrolopyrrolothiophrn) (PDPP3T) heterojunction. Experimental results reveal that the photodetector can have broadband photo response from 380 to 980 nm. Meanwhile, excellent responsivities and detectivity of 12.4 mA W−1, 2.2 × 1010 Jones at 380 nm and 0.1 mA W−1 and 5 × 108 Jones at 980 nm are achieved, which are ≈10 (UV band)/100 (NIR band) times high than that obtained on the pure MoS2‐based detector. Moreover, the flexibility of the device is investigated by conformal covering the device on a curved surface (R = 5 and 2.5 mm), it shows that the photo response remains almost the same as that measured on the planar substrate, indicating the possible application in the wearable electronics. [ABSTRACT FROM AUTHOR]

Two-dimensional van der Waals heterostructures have good application prospects in solar energy conversion due to their excellent optoelectronic performance. In this work, the electronic structures of Sc2CF2/Sc2CCl2, Sc2CF2/Sc2CBr2, and Sc2CCl2/Sc2CBr2 heterostructures, as well as their properties in photocatalysis and photovoltaics, have been comprehensively studied using the first-principles method. Firstly, both of the three thermodynamically and dynamically stable heterostructures are found to have type-II band alignment with band gap values of 0.58 eV, 0.78 eV, and 1.35 eV. Meanwhile, the photogenerated carriers in Sc2CF2/Sc2CCl2 and Sc2CF2/Sc2CBr2 heterostructures are predicated to follow the direct Z-scheme path, enabling their abilities for water splitting. As for the Sc2CCl2/Sc2CBr2 heterostructure, its photovoltaic conversion efficiency is estimated to be 20.78%. Significantly, the light absorption coefficients of Sc2CF2/Sc2CCl2, Sc2CF2/Sc2CBr2, and Sc2CCl2/Sc2CBr2 heterostructures are enhanced more than those of the corresponding monolayers. Moreover, biaxial strains have been observed to considerably tune the aforementioned properties of heterostructures. All the theoretical results presented in this work demonstrate the application potential of Sc2CX2/Sc2CY2 (X, Y = F, Cl, Br) heterostructures in photocatalysis and photovoltaics. [ABSTRACT FROM AUTHOR]

The hexagonal ferrite h-YbFeO3 grown on YSZ(111) by pulsed laser deposition is foreseen as a promising single multiferroic candidate where ferroelectricity and antiferromagnetism coexist for future applications at low temperatures. We studied in detail the microstructure as well as the temperature dependence of the magnetic properties of the devices by comparing the heterostructures grown directly on YSZ(111) (i.e., YbPt_Th0nm) with h-YbFeO3 films deposited on substrates buffered with platinum Pt/YSZ(111) and in dependence on the Pt underlayer film thickness (i.e., YbPt_Th10nm, YbPt_Th40nm, YbPt_Th55nm, and YbPt_Th70nm). The goal was to deeply understand the importance of the crystal quality and morphology of the Pt underlayer for the h-YbFeO3 layer crystal quality, surface morphology, and the resulting physical properties. We demonstrate the relevance of homogeneity, continuity, and hillock formation of the Pt layer for the h-YbFeO3 microstructure in terms of crystal structure, mosaicity, grain boundaries, and defect distribution. The findings of transmission electron microscopy and X-ray diffraction reciprocal space mapping characterization enable us to conclude that an optimum film thickness for the Pt bottom electrode is ThPt = 70 nm, which improves the crystal quality of h-YbFeO3 films grown on Pt-buffered YSZ(111) in comparison with h-YbFeO3 films grown on YSZ(111) (i.e., YbPt_Th0nm). The latter shows a disturbance in the crystal structure, in the up-and-down atomic arrangement of the ferroelectric domains, as well as in the Yb–Fe exchange interactions. Therefore, an enhancement in the remanent and in the total magnetization was obtained at low temperatures below 50 K for h-YbFeO3 films deposited on Pt-buffered substrates Pt/YSZ(111) when the Pt underlayer reached ThPt = 70 nm. [ABSTRACT FROM AUTHOR]

The development of innovative heterostructures made of ZnO nanowires is of great interest for enhancing the performances of many devices in the fields of optoelectronics, photovoltaics, and energy harvesting. We report an original fabrication process to form ZnO/ZnGa2O4 core–shell nanowire heterostructures in the framework of the wet chemistry techniques. The process involves the partial chemical conversion of ZnO nanowires grown via chemical bath deposition into ZnO/ZnGa2O4 core–shell nanowire heterostructures with a high interface quality following their immersion in an aqueous solution containing gallium nitrate heated at a low temperature. The double-step process describing the partial chemical conversion relies on successive dissolution and reaction mechanisms. The present finding offers the possibility to fabricate ZnO/ZnGa2O4 core–shell nanowire heterostructures at low temperatures and over a wide variety of substrates with a large surface area, which is attractive for nanostructured solar cells, deep-UV photodetectors, and piezoelectric devices. [ABSTRACT FROM AUTHOR]

A heterostructured Co-based electrocatalyst is successfully synthesized using bifunctional ligand Co metal–organic frameworks as precursors. The bifunctional ligands provide enough N and O atoms that can simultaneously convert Co ions into CoN x moieties, Co nanoparticles and Co oxides via one-step pyrolysis. The obtained electrocatalysts with heterostructured CoO x /Co nanoparticles encapsulated by porous conductive carbon rich in CoN x active sites deliver remarkable oxygen reduction reaction and oxygen evolution reaction activities. With the synergistic effects among these multifunctional components, a rechargeable zinc–air battery built with this electrocatalyst exhibits a high-power density and long-lasting rechargeability. [Display omitted] Rational construction of efficient and robust bifunctional oxygen electrocatalysts is key but challenging for the widespread application of rechargeable zinc-air batteries (ZABs). Herein, bifunctional ligand Co metal–organic frameworks were first explored to fabricate a hybrid of heterostructured CoO x /Co nanoparticles anchored on a carbon substrate rich in CoN x sites (CoO x /Co@Co N C) via a one-step pyrolysis method. Such a unique heterostructure provides abundant CoN x and CoO x /Co active sites to drive oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively. Besides, their positive synergies facilitate electron transfer and optimize charge/mass transportation. Consequently, the obtained CoO x /Co@Co N C exhibits a superior ORR activity with a higher half-wave potential of 0.88 V than Pt/C (0.83 V vs. RHE), and a comparable OER performance with an overpotential of 346 mV at 10 mA cm−2 to the commercial RuO 2. The assembled ZAB using CoO x /Co@Co N C as a cathode catalyst displays a maximum power density of 168.4 mW cm−2, and excellent charge–discharge cyclability over 250 h at 5 mA cm−2. This work highlights the great potential of heterostructures in oxygen electrocatalysis and provides a new pathway for designing efficient bifunctional oxygen catalysts toward rechargeable ZABs. [ABSTRACT FROM AUTHOR]

The In-O-Mo bond-modulated In 2 O 3 /Bi 2 MoO 6 S-scheme heterostructure was synthesized using the static electron assembly method. At the heterostructure interface, the formation of In-O-Mo bonds serves as an essential pathway for rapid carrier transfer/transport, resulting in carrier-oriented accumulation and significantly improving PNRR performance. [Display omitted] • In 2 O 3 /Bi 2 MoO 6 photocatalysts were synthesized using a mild electrostatic assembly method. • The formation of In-O-Mo bond at the heterogeneous interface was critical for rapid charge-carrier transportation and carrier oriented accumulation. • The carrier-oriented accumulation of carriers can trigger PNRR and OER half-reactions, facilitating efficient photocatalytic N 2 -to-NH 3 conversion. • 3 % In/BMO-based S-scheme heterostructure realized a nitrogen fixation rate of 150.9 μmol·g cat −1·h−1, demonstrating a significant performance improvement. Photocatalytic nitrogen fixation presents an eco-friendly approach to converting atmospheric nitrogen into ammonia (NH 3), but the process faces challenges due to rapid interface charge recombination. Here, we report an innovative charge transfer and oriented accumulation strategy using an In-O-Mo bond-modulated S-scheme heterostructure composed of In 2 O 3 /Bi 2 MoO 6 (In/BMO) synthesized using a simple electrostatic assembly. The unique interfacial arrangement with optimal photocatalyst configuration (3 % In/BMO) enabled enhanced photogenerated electron separation and transfer, leading to a remarkable nitrogen fixation rate of approximately 150.9 μmol·g cat −1·h−1 under visible light irradiation. The performance of the photocatalyst was 9-fold and 27-fold higher than that of its pristine components, Bi 2 MoO 6 and In 2 O 3 , respectively. The experimental and theoretical evaluation deemed interfacial In-O-Mo bonds crucial for rapid transfer and charge-oriented accumulation. Whereas the generated internal electric field drove the spatial separation and transfer of photo-generated electrons and holes, significantly enhancing the photocatalytic N 2 -to-NH 3 conversion efficiency. The proposed work lays the foundation for designing S-scheme heterostructures with highly efficient interfacial bonds, offering a promising avenue for substantial improvements in photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]

Using ZIF-67 as precursor, a bimetallic oxide heterostructure of CoO/MoO 3 @NC was synthesized, and the potential of its application as a modified separator material for lithium-sulfur batteries was explored. Furthermore, the CoO/MoO 3 @NC heterostructure exhibits advanced performance in lithium-sulfur batteries, thus paving the way for the design of novel lithium-sulfur battery separator materials. [Display omitted] • Hollow bimetallic oxide heterostructures CoO/MoO 3 @NC obtained by simple hydrothermal synthesis and calcination. • CoO/MoO 3 @NC consists of a bimetallic oxide heterostructure with an outer layer of capped carbon. The bimetallic oxide heterostructure provides more active sites for adsorption of polysulfides and the carbon coating significantly improves the electrical conductivity of the bimetallic oxide heterostructure. • The Li-S battery equipped with a CoO/MoO 3 @NC modified separator exhibits a high discharge capacity of 613 mAh g−1 at 1C and a capacity decay rate of 0.092% after 500 cycles at 0.5C. • The in-situ impedance test also reveals the remarkable role of CoO/MoO 3 @NC in adsorbing polysulfides and facilitating ion transport. Lithium-sulfur batteries (LSBs) have emerged as a promising energy storage system, but their practical application is hindered by the polysulfide shuttle effect and sluggish redox kinetics. To address these challenges, we have developed CoO/MoO 3 @nitrogen-doped carbon (CoO/MoO 3 @NC) hollow heterostructures based on porous ZIF-67 as separators in LSBs. CoO has a strong anchoring effect on polysulfides. The heterostructure formed after the introduction of MoO 3 increases the adsorption of polysulfides. The carbon coating outside the heterostructure improves the ion transmission efficiency of the battery, leading to enhanced electrochemical performance. The modified LSB demonstrates a low-capacity decay rate of 0.092% over 500 cycles at 0.5C, with a high discharge capacity of 613 mAh g−1 at 1C. This work presents a novel approach for the preparation of hollow heterostructure materials, aiming for high-performance LSBs. [ABSTRACT FROM AUTHOR]

2D van der Waals heterostructures (2D vdWHs) have been gaining significant attention in neuromorphic electronics. However, the facile synthesis of large‐scale, high‐quality freestanding 2D vdWHs remains challenge, particularly for organic counterparts due to susceptible nucleation behaviors and weak intermolecular interactions. Here, the study reports a graphene oxide (GO)‐assisted molecular crystal co‐assembly method for one‐step growth of centimeter‐scale freestanding heterostructures. This co‐assembly involves the simultaneous assembling of organic and GO precursors at the liquid–liquid interface, where the amphiphilic nature of GO nanosheets facilitates the diffusion of organic molecules and 2D nucleation of organic crystals, and the nanosheets also become enriched to grow a quasi‐solid film for the bilayer formation. Owing to integrated photosensitive and charge‐trapping properties as well as type II band structure, this heterostructure exhibits exceptional photonic synaptic behaviors, with a paired‐pulse facilitation index of 141% and image recognition of 91%. [ABSTRACT FROM AUTHOR]

The growth of ultrathin semiconductors is advantageous for photocatalysis due to improved photophysical properties and reduced charge recombination. Along these lines, templating the growth of semiconductors in confined spaces can allow control over semiconductor growth while also conferring the properties of the template to provide composite nanomaterial hybrids. Herein, the semiconductor In2S3 is grown in the organically‐modified interlayer space of Ti3C2TX MXene, a versatile 2D material with metallic character and broadband light absorption. The growth of 1–2 nm thick layers of In2S3 in the interlayer of MXene leads to a drastic increase in photocatalytic properties and light‐induced charge generation due to decreased interfacial charge transfer resistance. Interestingly, the hydrothermal conditions of In2S3 growth lead to partial oxidation of Ti3C2TX MXene to form anatase TiO2 nanocrystals, although this effect is strongly limited by increased In2S3 precursors due to passivation of the MXene surface. MXenes serve as effective templates for the confined growth of semiconductors, emphasizing the potential of MXene as a template for 2D material heterostructures. Overall, this work further develops MXene‐based 2D material composites, offering insights into the origins of the enhanced photocatalytic and photoelectrochemical properties, toward improvements in energy production and aqueous phase catalysis. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview of the production and modification of CZTS nanoparticles (NPs) and their application in electrocatalysis for water splitting. Various aspects, including surface modification, heterostructure design with carbon nanostructured materials, and tunable electrocatalytic studies, are discussed. A key focus is the synthesis of small CZTS nanoparticles with tunable reactivity, emphasizing the sonochemical method's role in their formation. Despite CZTS's affordability, it often exhibits poor hydrogen evolution reaction (HER) behavior. Carbon materials like graphene, carbon nanotubes, and C60 are highlighted for their ability to enhance electrocatalytic activity due to their unique properties. The review also discusses the amine functionalization of graphene oxide/CZTS composites, which enhances overall water splitting performance. Doping with non-noble metals such as Fe, Co., and Ni is presented as an effective strategy to improve catalytic activity. Additionally, the synthesis of heterostructures consisting of CZTS nanoparticles attached to MoS2-reduced graphene oxide (rGO) hybrids is explored, showing enhanced HER activity compared to pure CZTS and MoS2. The growing demand for energy and the need for efficient renewable energy sources, particularly hydrogen generation, are driving research in this field. The review aims to demonstrate the potential of CZTS-based electrocatalysts for high-performance and cost-effective hydrogen generation with low environmental impact. Vacuum-based and non-vacuum-based methods for fabricating CZTS are discussed, with a focus on simplicity and efficiency. Future developments in CZTS-based electrocatalysts include enhancing activity and stability, improving charge transfer mechanisms, ensuring cost-effectiveness and scalability, increasing durability, integrating with renewable energy sources, and gaining deeper insight into reaction processes. Overall, CZTS-based electrocatalysts show great promise for sustainable hydrogen generation, with ongoing research focused on improving performance and advancing their practical applications. [ABSTRACT FROM AUTHOR]