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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]

Investigating clean and sustainable hydrogen generation from water splitting requires cost‐effective and highly efficient electrocatalysts for the hydrogen evolution reaction (HER). Ruthenium (Ru)‐based heterostructure catalysts have emerged as promising alternatives to precious Pt, offering significant potential to overcome current bottlenecks. Recent advancements in Ru‐based heterostructure catalysts have focused on achieving a balance between catalytic activity and stability. An overview of these developments provides insights into catalytic mechanisms and facilitates the development of novel catalysts. This review begins with an exploration of the enhanced activity of heterostructure catalysts, followed by a critical summary of synthetic strategies employed to fabricate these catalysts and their catalytic performances for HER. Attention is then directed to experimental endeavors aimed at enhancing the HER performance of Ru‐based heterostructure catalysts. Finally, the opportunities and challenges in developing heterostructure catalysts from the perspectives of material design and synthesis is discussed. Through these discussions, a comprehensive understanding of Ru‐based heterostructure catalysts and inspire future research directions is aim to provided. [ABSTRACT FROM AUTHOR]

Enhancing the piezoelectricity of polymers while maintaining all components organic is still challenging but significantly important for developing flexible wearable energy harvesters and self‐powered devices. Here, a novel and versatile strategy is introduced to construct mixed‐dimensional all‐organic polymer heterostructures (MPHs) for enhanced piezoelectricity. By combining all‐polymer 1D nanofibers (NFs) with 2D crystals through epitaxial crystallization‐driven assembly (ECA), MPHs are engineered to capitalize on the synergistic effects of both dimensional nanostructures. The intrinsic piezoelectric activity of 1D NFs is amplified by the growth of 2D crystals, enhancing force‐sensitivity and overall piezoelectricity. The mixed‐dimensional assembly not only enables controlled in‐situ growth of MPHs, but also simultaneously induces preferential formation of electroactive phases through solvent‐induced phase transition. By modulating the epitaxial growth of 2D crystals on 1D NFs, effective tuning of MPH growth amount and morphology is achieved, resulting in significant improvements in deformability, dipole polarization, and durability. MPHs exhibit remarkable piezoelectric improvements, achieving higher output under lower‐level forces with a record‐high sensitivity of ≈670 mV kPa−1. Their superior responsivity enables the development of self‐powered wireless wearable motion‐monitoring systems for real‐time physiological movement detection and analysis. This work inspires the development of all‐organic piezoelectric devices for innovative flexible energy‐harvesting and sensing applications. [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]

As a neighbor of carbon in the periodic table, boron exhibits versatile structural and electronic configurations, with its allotropes predicted to possess intriguing structures and properties. Since the experimental realization of two‐dimensional (2D) boron sheets (borophene) on Ag(111) substrates in 2015, the experimental study of the realization and characteristics of borophene has drawn increasing interest. In this review, we summarize the synthesis and properties of borophene, which are mainly based on experimental results. First, the synthesis of borophene on different substrates, as well as borophane and bilayer borophene, featuring unique phases and properties, are discussed. Next, the chemistry of borophene, such as oxidation, hydrogenation, and its integration into heterostructures with other materials, is summarized. We also mention a few works focused on the physical properties of borophene, specifically its electronic properties. Lastly, the brief outlook addresses challenges toward practical applications of borophene and possible solutions. [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]

The development of a cost‐competitive and efficient electrocatalyst is both attractive and challenging for hydrogen production by hydrogen evolution reaction (HER). Herein, a facile glycol reduction method to construct Ru nanoclusters coupled with hierarchical exfoliated‐MXene/reduced graphene oxide architectures (Ru‐E‐MXene/rGA) is reported. The hierarchical structure, formed by the self‐assembly of graphene oxides, can effectively prohibit the self‐stacking of MXene nanosheets. Meanwhile, the formation of the MXene/rGA interface can strongly trap the Ru3+ ions, resulting in the uniform distribution of Ru nanoclusters within Ru‐E‐MXene/rGA. The boosted catalytic activity and underlying catalytic mechanism during the HER process are proved by density functional theory. Ru‐E‐MXene/rGA exhibits overpotentials of 42 and 62 mV at 10 mA cm−2 in alkaline and acidic electrolytes, respectively. The small Tafel slope and charge transfer resistance (Rct) values elucidate its fast dynamic behavior. The cyclic voltammetry (CV) curves and chronoamperometry test confirm the high stability of Ru‐E‐MXene/rGA. These results demonstrate that coupling Ru nanoclusters with the MXene/rGA heterostructure represents an efficient strategy for constructing MXene‐based catalysts with enhanced HER activity. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) is a promising electrocatalyst for the hydrogen evolution reaction (HER), despite suffering from low activity in non‐acidic conditions due to the high kinetic energy barrier of H2O dissociation. Herein, the synthesis of carbon nanosheet‐supported RuP/Ru heterostructures (RuP/Ru@CNS) from a natural polysaccharide is reported and demonstrates its behavior as an effective HER electrocatalyst in non‐acidic conditions. The RuP/Ru@CNS exhibits low overpotential (106 mV at 200 mA·cm−2) in alkaline electrolyte, exceeding most reported Ru‐based electrocatalysts. The electron shuttling between Ru atoms at the RuP/Ru interface results in a lowered energy barrier for H2O dissociation by electron‐deficient Ru atoms in the pure Ru phase, as well as optimized H* adsorption of electron‐gaining Ru atoms in the neighboring RuP. A low H* spillover energy barrier between Ru atoms at the RuP/Ru interface further boosts HER kinetics. This study demonstrates a sustainable method for the fabrication of efficient Ru‐based electrocatalysts and provides a more detailed understanding of interface effects in HER catalysis. [ABSTRACT FROM AUTHOR]

We develop a new type of heterostructure nanocomposite made of reduced graphene oxide-boron carbon nitride nanosheets (rGOBCN) by B–C covalent bonds. The rGO-BCN nanocomposite delivers a large specific surface and excellent electrochemical properties, and is then constructed into flexible fabric-based high-performance supercapacitor electrodes based on the microfluidic electrospinning technology. [ABSTRACT FROM AUTHOR]

A theoretical investigation of the hydrogen adsorption on a β12-borophene monolayer and a β12-borophene/graphene bilayer heterostructure is performed to tailor the substrate properties via functionalization to increase its hydrogen (H 2) physisorption strength and enhance its gravimetric capacity. The results using the density-functional theory show that the H 2 adsorption energy significantly increases as the substrate changes from monolayer to bilayer heterostructure. This enhancement in H 2 adsorption energy is attributed to the synergetic effects of the interlayer interaction in the heterostructure via analysis of the chemical bonding. The lithium decoration of the bilayer heterostructure has indeed increased both the H 2 adsorption energy and gravimetric capacity. Further enhancement of these latter attributes is shown to be plausible to achieve through the application of an electric field normal to the surface and directed upward toward the molecules. The thermodynamic analysis based on the Langmuir adsorption model finds that the high storage capacity should be maintained high with an effective gravimetric capacity of 13.64 wt% at ambient conditions. Our findings demonstrated that the Li-decorated β12-borophene/graphene bilayer heterostructure should be a promising candidate for efficient hydrogen storage applications. [Display omitted] • DFT adsorption study of H 2 on Li-decorated β12-borophene/graphene hetero-structure. • Findings reveal synergistic effect of combining B/G in enhancing E ads and gravimetric capacity. • Thermodynamic analysis confirms gravimetric capacity of 13.64 wt% at ambient condition. • Application of perpendicular electric field to B/G enhances more gravimetric capacity. • Li-decorated β12-borophene/graphene is strong candidate material for H 2 storage. [ABSTRACT FROM AUTHOR]

Twisted isotropic-anisotropic van der Waals heterostructures provide a platform for controlling the electronic and phononic properties of 2D materials and inducing in-plane anisotropy in some isotropic materials. Herein, angle-resolved polarized Raman spectroscopy and photoluminescence spectroscopy are used to investigate the induced in-plane anisotropy of the quasiparticles in the twisted MoS2/CrOCl heterostructures. Both the phonons ( E g 2 MoS 2 and A g 1 MoS 2 modes) and excitons (A and B excitons) in MoS2 represent a strong in-plane orientation dependence, and the maximum intensities are along the [100]CrOCl. The induced anisotropy ratios of phonons vary continuously in the range from 1.22 to 1.13 for the E g 2 MoS 2 mode and 1.15 to 1.09 for the A g 1 MoS 2 mode with changing twisted angles, which originate from the anisotropic carrier mobility induced by the localized charge distribution from the anisotropic CrOCl substrates, and are further tuned by the uniaxial local limit of charge carriers caused by 1D moiré pattern. Our findings provide a way to controllably regulate the induced in-plane optical anisotropy in heterostructures. [ABSTRACT FROM AUTHOR]

Visible-light-driven Bi2WO6/BiVO4 (BWO/BVO) heterostructures were obtained by joining BWO and BVO n-type semiconductors. A novel and green metathesis-assisted molten salt route was applied to synthesize BWO/BVO. This route is straightforward, high-yield, intermediate temperature, and was successful for obtaining BWO/BVO heterostructures with several ratios (1:1, 1:2, 2:1 w/w). Besides, the 1BWO/1BVO was decorated with Ag nanoparticles (Ag-NPs, 6 wt.%) and graphene (G, 3 wt.%), applying simple and environmentally responsible procedures. The heterostructures were characterized by XRD, Raman, UV–Vis DRS, TEM/HRTEM, PL, and Zeta potential techniques. Ag-NPs and G effectively boosted the photocatalytic activity of 1BWO/1BVO for degrading tetracycline (TC) and rhodamine B (RhB) pollutants. A lab-made 19-W blue LED photoreactor was designed, constructed, and operated to induce the photoactivity of BWO/BVO heterostructures. The low-rated power consumption of the photoreactor (0.01–0.04 kWh) vs. the percent degradation of TC or RhB (%XTC = 73, %XRhB = 100%) is one of the outstanding features of this study. Besides, scavenger tests determined that holes and superoxides are the main oxidative species that produced TC and RhB oxidation. Ag/1BWO/1BVO exhibited high stability in reuse photocatalytic cycles. [ABSTRACT FROM AUTHOR]

A one dimensional (1D) hierarchical structure with hybrid components is extremely attractive for catalytic application considering the integrated properties and synergistic effect of its individual components. In this work, an effective approach combined with a hydrothermal reaction, water bath deposition, and postcalcination treatment is developed to decorate NiCo2O4 nanoparticles (NPs) on MnO2 nanowires (NWs), leading to the formation of 1D hierarchical heterostructures as efficient oxidase mimics for the detection of glutathione. The oxidase catalytic activity of the as-prepared MnO2@NiCo2O4 composites is much higher than that of individual NiCo2O4 NPs and MnO2 NWs because of the synergistic effect between the two components. Owing to the superior catalytic efficiency of the prepared MnO2@NiCo2O4 nanowires, a colorimetric route for the rapid and accurate detection of glutathione has been developed. This shows that the 1D hierarchical MnO2@NiCo2O4 composites as catalytic materials potentially have a good application prospect. [ABSTRACT FROM AUTHOR]

Recently, the combination of two different two-dimensional (2D) semiconductors to generate van der Waals (vdW) heterostructures has emerged as an effective strategy to tailor their physical properties, paving the way for the development of next-generation devices with improved performance and functionality. In this work, we designed an MoS2/MoGe2N4 heterostructure and explored its electronic structures, optical properties and contact characteristics using first-principles calculations. The MoS2/MoGe2N4 heterostructure is predicted to be energetically, thermally and dynamically stable, indicating its feasibility for experimental synthesis in the future. The MoS2/MoGe2N4 heterostructure forms type-I band alignment, suggesting that it can be considered as a promising material for optoelectronic devices, such as light-emitting diodes, and in laser applications. Furthermore, the type-I MoS2/MoGe2N4 heterostructure has enhanced optical absorption in both the visible and ultraviolet regions. More interestingly, the electronic properties and contact characteristics of the MoS2/MoGe2N4 heterostructure can be tailored by applying in-plane biaxial strain. Under the application of compressive and tensile strains, transformations between type-I and type-II band alignments and between semiconductor and metal can be achieved in the MoS2/MoGe2N4 heterostructure. Our findings could provide useful guidance for experimental synthesis of materials based on the MoS2/MoGe2N4 heterostructure for electronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

TThe object of research is the donor-acceptor compound, organic and hybrid heterostructures based on it. The paper is focused on a comprehensive approach to solving the problem of the efficiency of light-emitting devices, finding new technological and design solutions for the use of organic compounds as multifunctional materials for various types of light-emitting devices. The paper presents the multifunctional application of a planar 2D molecule as an emission layer for typical and inverted types of light-emitting heterostructures, as well as a matrix for a host-guest system using inorganic quantum dots. The developed light-emitting structures are characterized by external quantum efficiency typical for fluorescent devices, but good stability over the entire length of the consumption voltage. QLED brightness is 1600 cd·m-2 and EQE 1.4 %, which are good parameters for use in display technology. Organic LEDs based on planar molecules are promising candidates for use in modern lighting systems. A separate advantage of these light-emitting structures is the multifunctionality of using one compound for different types of light-emitting structures, including inverted heterostructures. Special attention is paid to the technological and design implementation of invert structures, since their geometry allows direct connection to the back board of the n-channel transistor on the substrate. In addition, organic LEDs have low energy consumption and are environmentally friendly due to the absence of toxic substances in their architecture, which creates the prerequisites for saving energy resources and reducing the industrial burden on the environment. [ABSTRACT FROM AUTHOR]

In recent years, 2D materials and their heterostructures have started to offer an ideal platform for high-performance photodetection devices. In this work, a highly responsive, self-powered photodetector based on PtSe2/MoS2 van der Waals heterostructure is demonstrated. The device achieves a noteworthy wide band spectral response from visible (405 nm) range to the near infrared region (980 nm). The remarkable photoresponsivity and external quantum efficiency up to 4.52 A/W, and 1880% are achieved, respectively, at 405 nm illumination with fast response time of 20 ms. In addition, the photodetector exhibits a decent photoresponsivity of 33.4 mA/W at zero bias, revealing the photodetector works well in the self-driven mode. Our work suggests that a PtSe2/MoS2 heterostructure could be a potential candidate for the high-performance photodetection applications. [ABSTRACT FROM AUTHOR]

This study details the rational design and synthesis of Cu2ZnSnS4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS–A heterojunctions. As the concentration of titanium dioxide (TiO2) varied, the morphology of CZTS shifted from floral patterns to sheet-like structures. The resulting CZTS–A heterostructures underwent comprehensive characterization through photoelectrochemical response assessments, optical measurements, and electrochemical impedance spectroscopy analyses. Detailed photoelectrochemical (PEC) investigations demonstrated notable enhancements in photocurrent density and incident photon-to-electron conversion efficiency (IPCE). Compared to pure anatase electrodes, the optimized CZTS–A heterostructures exhibited a seven-fold increase in photocurrent density and reached a hydrogen production efficiency of 1.1%. Additionally, the maximum H2 production rate from these heterostructures was 11-times greater than that of pure anatase and 250-times higher than the original CZTS after 2 h of irradiation. These results underscore the enhanced PEC performance of CZTS–A heterostructures, highlighting their potential as highly efficient materials for solar water splitting. Integrating Cu2ZnSnS4 nanoparticles (NPs) within TiO2 (anatase) heterostructures implied new avenues for developing earth-abundant and cost-effective photocatalytic systems for renewable energy applications. [ABSTRACT FROM AUTHOR]

Carbon-based magnetic metal composites derived from metal–organic frameworks (MOFs) are promising materials for the preparation of broadband microwave absorbers. In this work, the leaf-like co-doped porous carbon/carbon nanotube heterostructure was obtained using ZIF-L@ZIF-67 as precursor. The number of carbon nanotubes can be controlled by varying the amount of ZIF-67, thus regulating the dielectric constant of the sample. An optimum reflection loss of −42.2 dB is attained when ZIF-67 is added at 2 mmol. An effective absorption bandwidth (EAB) of 4.8 GHz is achieved with a thickness of 2.2 mm and a filler weight of 12%. The excellent microwave absorption (MA) ability is generated from the mesopore structure, uniform heterogeneous interfaces, and high conduction loss. The work offers useful guidelines to devise and prepare such nanostructured materials for MA materials. [ABSTRACT FROM AUTHOR]

Electrical computers have revolutionized society over the past several decades, but questions have remained about their ability to perform in extreme environments, such as their stability at high-temperature conditions. This has motivated the recent surge of interest in developing mechanical computing platforms at all length scales, including the nanoscale, in which traditional electrical computers are augmented with mechanical ones. However, the most proposed nanomechanical bits are volatile memory bits based on the dynamic response of nanomechanical resonators, and as such, there is a need to develop robust and reprogrammable entirely non-volatile nanomechanical bits. Here, we exploit the multiple quasi-stable configurations of the graphene/fullerene/graphene (GFG) van der Waals heterostructure to work as a novel nonvolatile nanomechanical bit. The GFG heterostructure is unique and robust in that it can return to its initial state without further mechanical input, it can be used for logic functions at relevant operating temperatures through simple application of uniaxial strain, it can exhibit reprogrammability between five basic logic gates (NOT, AND, NAND, OR, NOR) by varying the magnitude or direction of applied strain, and it can be used to represent combinatorial logic through full and half adders. These findings provide a new opportunity to develop mechanical computers based on the large class of nanomaterials. [ABSTRACT FROM AUTHOR]

Charge transfer is a fundamental interface process that can be harnessed for light detection, photovoltaics, and photosynthesis. Recently, charge transfer was exploited in nanophotonics to alter plasmon polaritons by involving additional non-polaritonic materials to activate the charge transfer. Yet, direct charge transfer between polaritonic materials has not been demonstrated. We report the direct charge transfer in pure polaritonic van der Waals (vdW) heterostructures of α-MoO3/graphene. We extracted the Fermi energy of 0.6 eV for graphene by infrared nano-imaging of charge transfer hyperbolic polaritons in the vdW heterostructure. This unusually high Fermi energy is attributed to the charge transfer between graphene and α-MoO3. Moreover, we have observed charge transfer hyperbolic polaritons in multiple energy–momentum dispersion branches with a wavelength elongation of up to 150%. With the support from the density functional theory calculation, we find that the charge transfer between graphene and α-MoO3, absent in mechanically assembled vdW heterostructures, is attributed to the relatively pristine heterointerface preserved in the epitaxially grown vdW heterostructure. The direct charge transfer and charge transfer hyperbolic polaritons demonstrated in our work hold great promise for developing nano-optical circuits, computational devices, communication systems, and light and energy manipulation devices. [ABSTRACT FROM AUTHOR]

Lanthanide-doped nanoparticles (LnNPs) show unique optical properties and have been demonstrated in various applications, including imaging, optogenetics, photothermal therapy, photodynamic therapy, light-controlled release/cross-linking, anticounterfeiting, lasing, sensing, and super-resolution microscopy. One of the key and urgent limitations of LnNPs is the weak and narrow absorption of lanthanides. Fabrication of heterostructures will overcome this hurdle and enhance the performance of LnNPs. Developing novel heterostructures to enhance the absorption of lanthanides and studying the energy transfer pathways and efficiencies are of broad interest to the chemical and physical research community. There is currently no systematic review to summarize different types of LnNP heterostructures. Thus, this review will summarize five types of heterostructures combining LnNPs with organic and inorganic dyes, plasmonics, semiconducting quantum dots, and metal–organic frameworks. The enhancement of absorption and the improvement of light conversion performance are compared and discussed. This review also discusses the energy transfer pathways and efficiencies between LnNPs and other components and provides suggestions to form heterostructures with enhanced absorption and efficient energy transfer for future applications. We hope this review will further inspire active development and study of lanthanide-based heterostructures with stronger absorption, better light conversion performance, and ease of multifunctionality. [ABSTRACT FROM AUTHOR]

Interest in fullerene-based polymer structures has renewed due to the development of synthesis technologies using thin C60 polymers. Fullerene networks are good semiconductors. In this paper, heterostructure complexes composed of C60 polymer networks on atomically thin dielectric substrates are modeled. Small tensile and compressive deformations make it possible to ensure appropriate placement of monolayer boron nitride with fullerene networks. The choice of a piezoelectric boron nitride substrate was dictated by interest in their applicability in mechanoelectric, photoelectronic, and electro-optical devices with the ability to control their properties. The results we obtained show that C60 polymer/h-BN heterostructures are stable compounds. The van der Waals interaction that arises between them affects their electronic and optical properties. [ABSTRACT FROM AUTHOR]

Stochastic simulation algorithm for solving exciton transport in a 3D layered semiconductor heterostructure is developed. The problem is governed by a transient drift-diffusion-recombination equation with Dirichlet and Neumann mixed boundary conditions. The semiconductor is represented as an infinite multilayer of finite thickness along the transverse coordinate z. The multilayer is composed by a set of sublayers of different materials so that the excitons have different diffusion and recombination coefficients in each layer. Continuity of solutions and fluxes at the plane interfaces between layers are imposed. The stochastic simulation algorithm solves the transport problem by tracking exciton trajectories in accordance with the probability distributions represented through the Green function of the problem in each sublayer. The method is meshless, the excitons jump only over the plane boundaries of the layers. This explains the high efficiency of the method. Simulation results for transport problems with different mixed boundary conditions are presented. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDCs), represented by MX2 (where M = Mo, W and X = S, Se, and Te), and more recently, their moiré superlattices (i.e., formed by superimposing layers of TMDCs with different rotation angles) have attracted considerable interest due to their excellent physical properties and unique nanoscale functionalities. Compared to graphene, the literature indicates that TMDCs offer a competitive advantage in optoelectronic technologies, primarily owing to their compositionally controlled non-zero bandgap. These two-dimensional (2D) nanostructured single or multiple layers exhibit remarkable properties that differ from their bulk counterparts. Moreover, stacking different TMDC monolayers also forms heterostructures and introduces unique quantum effects and extraordinary electronic properties, which is particularly promising for next-generation optoelectronic devices and photo(electro)catalytic applications. Therefore, in this review, we also highlight the new possibilities in the formation of 2D/2D heterostructures of MX2-based materials with moiré patterns and discuss the main critical challenges related to the synthesis and large-scale applications of layered MX2 and MX2-based composites to spur significant advances in emerging optoelectronic and photo(electro)catalytic applications. [ABSTRACT FROM AUTHOR]