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Paper‐based photodetectors have emerged as reliable candidates for wearable electronics due to their low‐cost, degradability and excellent bending properties. However, the application of quantum dots (QDs) to paper‐based devices remains a challenge due to the low carrier mobility. In this work, lead sulfide (PbS) QDs are successfully applied to paper‐based devices by constructing the amorphous indium gallium zinc oxide (a‐IGZO)/PbS QDs‐EDT heterojunction to enhance the photoconductive gain of the QDs film. The effect of different paper substrates are investigated on device performance and demonstrate that the heterojunction is not suitable for the fiber‐like paper substrate. Heterojunction devices based on Senyan paper and glass paper exhibit stable detection performance with detectivity of 1.71 × 1010 and 3.19 × 1011 Jones, respectively. Benefit from the unique micro‐morphology, the Senyan paper‐based device exhibits excellent bending resistance and remained stable after 1000 bends. [ABSTRACT FROM AUTHOR]

Dual‐ion batteries have been considered as a competitive energy‐storage device. However, owing to the lack of suitable high‐capacity density and rapid‐charging electrode materials, designing a cost‐effective and high‐performance dual‐ion battery is still a great challenge. Herein, an ultrahigh‐capacity dual‐ion battery is constructed based on a carbon‐nanotubes (CNTs) containing SnS2‐MoS2@CNTs heterojunction anode and highly crystalline free‐standing graphite paper serves as cathode. The SnS2‐MoS2@CNTs heterojunction consisting of ultrathin nanosheets was prepared via a facile two‐step hydrothermal method and shows flower‐like morphology and high crystallinity. Benefiting from the unique design concept, the graphite paper/SnS2‐MoS2@CNTs dual‐ion battery delivers a high capacity of 274.2 mAh g−1 at 100 mA g−1 and has an outstanding capacity retention of 95 % after 300 cycles under 400 mA g−1. Even at a high current density of 2 A g−1 the battery still retains a considerable capacity of 112.3 mAh g−1. More importantly, the battery shows an extremely low self‐discharge of 0.006 % h−1 after resting for 24 h. Characterization using SEM and XRD further demonstrate the excellent cycling stability and good reversibility. Consequently, this constructed dual‐ion battery could be a promising energy storage device and provide new insights for the design of high‐performance dual‐ion batteries. [ABSTRACT FROM AUTHOR]

Understanding the properties and structure of reactant water molecules at the electrolyte solution/electrode interface is relevant to know the mechanisms of hydrogen evolution reaction (HER). However, this approach has rarely been implemented due to the elusive local microenvironment in the vicinity of the catalyst. Taking the Ni−CeO2 heterostructure immobilized onto carbon paper (Ni−CeO2/CP) as a model, the dynamic behavior of adsorbed intermediates during the reaction was measured by in situ surface‐enhanced infrared absorption spectroscopy with attenuated total reflection configuration (ATR‐SEIRAS). Theoretical calculations are used in combination to comprehend the potential causes of increased HER activity. The results show that the O−H bond of adsorbed water at the electrolyte solution/electrode interface becomes longer for promoting the dissociation of water and accelerating the kinetically slow Volmer step. In addition, forming the Ni−CeO2 heterostructure interface optimizes the hydrogen adsorption Gibbs free energy, thus increasing HER activity. Therefore, the Ni−CeO2/CP electrode exhibits remarkably low HER overpotentials of 37 and 119 mV at 10 and 100 mA cm−2, which are close to commercial Pt/C (16 and 102.6 mV, respectively). [ABSTRACT FROM AUTHOR]

This paper reports a concise strategy for the controlled preparation of Pd@g‐C3N4/TiO2 photocatalysts rich in oxygen vacancies. The scheme forms black TiO2 with oxygen vacancies on a carbon nitride material by in‐situ growth and heat treatment, and then utilizes solvothermal reduction to load metallic palladium into the material. The composites were structurally analyzed using Fourier transform infrared (FT‐IR), X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction analysis (XRD), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR), scanning electron microscopy (SEM), elemental mapping, diffuse reflectance spectroscopy (DRS), and inductively coupled plasma (ICP) analysis. The results show that the oxygen vacancies in the black TiO2 materials prepared by the method reported in this paper can effectively improve the separation efficiency of the photogenerated electron–hole pairs and prolong the lifetime of the charge carriers by inhibiting charge recombination. In addition, the heterojunction structure formed between TiO2 and g‐C3N4 materials also enhances the photocatalytic performance of the materials to some extent. After a simple optimization of the conditions, the Pd@g‐C3N4/TiO2 photocatalyst could promote the Suzuki–Miyaura CC coupling reactions under mild conditions (room temperature, 30 W LED lamp, λ = 455 nm), and good biaryl yields were obtained (optimum yield = 99%). It is very noteworthy that the photogenerated electrons and holes generated by the photoexcited catalyst were confirmed to be the main active species in the photocatalytic process of the catalyst by radical trapping assay and EPR test. The Pd@g‐C3N4/TiO2 material reported in this paper has excellent photocatalytic activity and stability in use, which provides a new reference scheme for wider green synthesis and catalysis. [ABSTRACT FROM AUTHOR]

Organic electrode materials (OEMs) are emerging green power because of the promising advantages such as environmental friendliness, abundant sources, easy recycling, and structural diversity. However, several inherent issues, including low electronic conductivity, dissolution of active materials, and particle pulverization restrict their practical application. MXene, as a novel 2D material has exhibited enormous potential to solve the issues of OEMs due to its high conductivity, unique structure, exceptional mechanical property, and abundant surface groups. Up to now, various effective strategies have been presented and achieved positive effects, such as constructing heterojunction structures, in situ assembly, dip-coating, preparing freestanding MXene paper, etc. Nonetheless, comprehensive review of the progress and status is rare. Herein, an overview of the application of MXene in organic electrode materials for rechargeable batteries is systematically put forward. Meanwhile, recent progress and future development directions are presented. This review can serve as a guide for future research. [ABSTRACT FROM AUTHOR]

In this paper, we report the first Q‐switching operation utilizing black phosphorus (BP)/SnSe2 heterojunction as the saturable absorber (SA) in an Er‐doped fiber laser. The BP/SnSe2 heterojunction was prepared by the liquid phase combination method and its properties were observed. Stable Q‐switching operations were achieved based on the BP/SnSe2 SA. The maximum peak power of 71.27 mW and the minimum pulse width of 910 ns were produced, respectively. This paper demonstrates the pulse modulation characteristics of BP/SnSe2 heterojunction SA in the midinfrared region for the first time, laying an important foundation for the application of heterojunction based on BP and two‐dimensional transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]

Increasing the active site of redox reactions on the surface of photocatalysts and accelerating the separation and transfer of photogenerated electron‐hole pairs are effective methods to improve the hydrogen evolution of composite photocatalysts. Non‐precious metal Ni photo‐deposition is anchored in situ on the ZnIn2S4 surface to generate the cocatalyst Ni(OH)2, which improves the photocatalytic hydrogen evolution performance of the composite sample. Under visible light irradiation, the ZnIn2S4 semiconductor stimulates photon‐generated carriers. Ni2+ acts as the defect center of photogenerated electron‐hole pairs to promote the separation of carriers. It serves as the capture site of light‐generated holes to reduce the carrier recombination rate so that the light‐generated electrons on the ZnIn2S4 surface promote H+ reduction in H2. Ni(OH)2 provides the active site for oxidation reaction on the surface of semiconductor materials, allowing the carrier to be consumed faster and improving the photocatalytic stability of semiconductor materials. The addition of 2 wt% Ni2+ resulted in a hydrogen evolution rate of 10 066 µmol·g−1 ·h−1 for ZnIn2S4/Ni(OH)2, which was 2.5 times higher than that of pure ZnIn2S4. This paper presents a reference case for enhancing the stability of sulfide to promote its photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

High‐speed and highly sensitive infrared photodetectors are regarded as one of the most essential components in modern photonic devices and technology because of constantly emerging application scenarios. In this paper, an ultrafast and extremely low noise mid‐infrared (MIR) photodetector is reported at both room and cryogenic temperatures by leveraging the high‐mobility 2D electron gas (2DEG) at the polar CdTe/PbTe heterostructure interface. The detector simultaneously exhibits a peak detectivity of ≈4.2 × 1011 Jones with rapid response in the order of 10 ns, which is substantially superior to the state‐of‐the‐art 2DEG MIR detectors made of 2D layered materials. The ultrafast response with extremely low noise of the 2DEG photodetector is attributed to the unique band alignment at the interface. The practical infrared imaging application is further showcased using the 2DEG MIR detector by revealing the fine features of a MIR radiation target. This work highlights the promising prospect of utilizing the unique 2DEG interface in the field of high‐speed and highly sensitive MIR detection. [ABSTRACT FROM AUTHOR]

In this paper, a simple template‐free one‐step hydrothermal method was used to construct three‐dimensional In−Zn−Cd−S composite materials. By changing the ratio of In3+/(Zn2++Cd2+) and controlling the band gap of semiconductor, a novel efficient and stable photocatalyst was designed. In−Zn−Cd−S composite showed good adsorption capacity and photocatalytic activity. When In3+/(Zn2++Cd2+) was equal to 1/5, the photocatalytic activity of the composite was the highest. The degradation rate of RhB could reach 92.6 % within 5 min, and 97.6 % after 15 min. The results of cyclic experiments show that the IZCS‐4 catalyst has good cyclic performance and structural stability. According to the free radical capture experiment, the main effect of IZCS‐4 on the photodegradation of organic pollutants is H+ and ⋅O2−. The enhanced photocatalytic activity of the alloy semiconductor material is mainly because it can effectively separate the photogenerated carriers and successfully inhibit the photocorrosion of In2S3 monomer. [ABSTRACT FROM AUTHOR]

For two‐dimensional (2D) layered material heterojunctions, dynamic modulation of band alignments allows for the design of devices with flexible multi‐functional applications. In this paper, a device structure is presented based on a MoTe2/SnSe2 field‐effect transistor. By applying a bias voltage to the electrostatic gate, the gate voltage is adjusted from negative to positive, causing the heterojunction to transition from type‐III band alignment to type‐II band alignment. The working mechanism and device performance of the heterojunctions with different band alignments are investigated. The device exhibited outstanding detection range (from ultraviolet to infrared), detectivity (2.42 × 109 Jones), and speed (1.3 ms). Under a positive gate voltage, a higher ratio of light current to dark current (2×103) is achieved. To further demonstrate the potential of the high‐performance devices, their reliability is confirmed through their performance in image recognition using deep learning. [ABSTRACT FROM AUTHOR]

As an environmentally friendly technology, photocatalysis technology has great application prospects in the fields of photoelectric energy and environmental pollutants treatment, and its core is photocatalyst. In recent years, perovskite materials with a narrow band gap, high quantum efficiency, and high carrier mobility have been widely concerned to use as photocatalysts. However, as to a single perovskite, the electron–hole separation rate is still low. In this paper, CsPbBr3/UiO‐66 composite photocatalyst was prepared based on a heterojunction strategy. CsPbBr3/UiO‐66 photocatalyst has excellent photocatalytic performance: The degradation rate of methyl orange (MO) in aqueous solution is more than 90% in 90 min, which is much higher than that of original CsPbBr3 (57.7% in 90 min). Based on various characterization techniques, our study verified the formation of a Z‐scheme heterojunction between CsPbBr3 and UiO‐66. At the same time, the improved photocatalytic performance of CsPbBr3/UiO‐66 is due to the efficient Z‐scheme charge migration mechanism in CsPbBr3/UiO‐66. This work is expected to provide a new opportunity to regulate the photocatalytic performance of perovskite by heterojunction strategy. [ABSTRACT FROM AUTHOR]

The accumulation of organic dyes in water and their consequent detrimental effect to ecological environment have attracted worldwide extensive attention. It is urgent to develop rapid and efficient method to degrade organic dyes. In this paper, an efficient CdZnS/SnS2/SnO2 heterojunction is successfully prepared by sequential template approach and hydrothermal method. Comparison with CdZnS and SnS2/SnO2, the heterogeneous structure of CdZnS/SnS2/SnO2 greatly enhances the photocatalytic degradation ability of Rhodamine B (RhB). The apparent reaction rate of CdZnS/SnS2/SnO2 heterostructure is around 12.71 and 16.69 times higher than those of SnS2/SnO2 and CdZnS, respectively, reaching 0.0267 min−1. After CdZnS/SnS2/SnO2 photocatalysis of RhB solution, the BOD/COD ratio increases from 0.168 to 0.725, indicating that the biodegradability is greatly improved. It has been proved that ⋅OH, ⋅O2−, h+ and e− are the main active species involved in the degradation process. In addition, the CdZnS/SnS2/SnO2 exhibits good stability and reusability, with little change in the photocatalytic activity after five cycles. Its superior removal activity is mainly due to the formation of heterojunction improved light harvesting and enhanced separation efficiency. This work provides a new insight for photocatalytic degradation of organic dye wastewater by solar light. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY), a new two‐dimensional carbon isomer material, has received much attention due to its excellent properties, but has been less applied in the field of photocatalytic hydrogen production. Different from the conventional method, in this paper, GDY−CuI binary heterojunctions are prepared by the one‐pot method, and then GDY−CuI is combined with different morphologies of NiCoLDH (NiCoLDH‐F and NiCoLDH‐R; LDH=layered double hydroxide) through morphology modulation to form NiCoLDH−CuI−GDY double S‐scheme heterojunction catalysts. On the one hand, NiCoLDH could provide sufficient anchor sites for GDY−CuI, which is conducive to the separation and transport of electrons at the contact interface and provides abundant reaction sites for the hydrogen precipitation reaction. NiCoLDH in the form of nanorods is more stable and provides more active sites for hydrogen precipitation than NiCoLDH in the form of nanoflowers. On the other hand, the construction of double S‐scheme heterojunctions can promote electron transfer and exhibit strong redox ability in photocatalytic reactions, so the hydrogen precipitation activity is enhanced. Most importantly, both NiCoLDH‐F−CuI−GDY (12.09 μmol ⋅ h−1) and NiCoLDH‐R−CuI−GDY (13.47 μmol ⋅ h−1) exhibited excellent hydrogen precipitation activity. This experiment provides a new strategy for the construction of an efficient and environmentally friendly multicatalytic system. [ABSTRACT FROM AUTHOR]

Programmable devices can be easily switched between n‐type and p‐type devices by applying an electric field and are promising candidates for simplifying the currently used fabrication process and increasing programmable flexibility. This paper proposes a 2D WSe2/3D Ge heterojunction field‐effect transistor (JFET) with a top metal‐insulator semiconductor gate. The n‐type and p‐type JFETs are realized based on one device structure; furthermore, the n‐type JFET can be converted into p‐type and vice versa under the control of top‐gate voltages of different polarities. The nJFET and pJFET has low subthreshold swings of 102 and 65 mV dec−1 with a high on/off ratio of ≈105, respectively. Moreover, a visible‐infrared wavelength‐distinguishing photodetector is implemented based on this device. It exhibits a bidirectional photoresponse, wherein the photocurrent polarity is reversed depending on the wavelength of light. Under illumination at 532 nm, positive photoresponsivity is realized through the effective charge separation of the heterojunction. In contrast, the JFET has a negative photoresponsivity at an infrared wavelength of 1550 nm, which is related to type‐I band alignment and the photogating effect. These results indicate that the device has promising potential as a multifunctional optoelectronic device. [ABSTRACT FROM AUTHOR]

High‐performance broadband photodetectors (PDs) are essential components in spectroscopy, remote sensing, imaging, and light communication applications. In this paper, Sb2Se3 nanoparticles (NPs) are uniformly deposited on TiO2 nanorod arrays (NRs) to construct a type II heterojunction with good interfacial contact by a simple two‐step potentiostatic electrochemical deposition method combined with N2 atmosphere annealing at 280, 290 and 300 °C to control the amount of Se in Sb2Se3. A good interfacial contact between Sb2Se3 and TiO2 is conducive to the separation and transport of photogenerated carriers. Sb2Se3/TiO2 PDs exhibit excellent self‐powered photoresponse in a broad spectral range from ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) due to the combined effects of high light absorption, low defect density, and more suitable band alignment. The optimal parameters with a responsivity of 13.48 A W−1, detectivity of 7.9 × 1011 Jones, and response time of 18/20 µs are demonstrated for the PDs annealed at 290 °C. The excellent performance broadband Sb2Se3/TiO2 PDs are used to construct the application models in the light communication for light encryption and flaw detection. This work opens up a new strategy for Sb2Se3/TiO2 PDs in multifunctional applications. [ABSTRACT FROM AUTHOR]

In this paper, a type II CeO2/Bi2O2CO3 heterojunction composite photocatalytic material with different proportions was synthesized. The structure, morphology, and photocatalytic properties of CeO2/Bi2O2CO3 were analyzed by XRD, SEM, and XPS. SEM showed that CeO2 and Bi2O2CO3 are closely combined, which is conducive to carrier migration and separation and improves the stability of the material. The light absorption properties of CeO2/Bi2O2CO3 composites were tested by UV‐vis DRS. The photocatalytic performance of the CeO2/Bi2O2CO3 composite system was studied with chlortetracycline hydrochloride as the target material. The results showed that under the conditions of 12.5 % CeO2, 0.5 g/L catalyst, and 20 mg/L chlortetracycline hydrochloride, the photocatalytic performance of the composite system was the highest, reaching 95.2 %. Moreover, the electrochemical properties of CeO2 and Bi2O2CO3 were tested and their potential, conduction band, and valence band values were obtained. At the same time, we propose the mechanism of type II electron transfer in CeO2/Bi2O2CO3 composites. [ABSTRACT FROM AUTHOR]

In this paper, 2D/3D heterojunction diodes have been fabricated by pulsed laser deposition (PLD) of MoS2 on 4H‐SiC(0001) surfaces with different doping levels, i.e., n− epitaxial doping (≈1016 cm−3) and n+ ion implantation doping (>1019 cm−3). After assessing the excellent thickness uniformity (≈3L‐MoS2) and conformal coverage of the PLD‐grown films by Raman mapping and transmission electron microscopy, the current injection across the heterojunctions is investigated by temperature‐dependent current–voltage characterization of the diodes and by nanoscale current mapping with conductive atomic force microscopy. A wide tunability of the transport properties is shown by the SiC surface doping, with highly rectifying behavior for the MoS2/n− SiC junction and a strongly enhanced current injection for MoS2/n+ SiC one. Thermionic emission is found the dominant mechanism ruling forward current in MoS2/n− SiC diodes, with an effective barrier ΦB = (1.04 ± 0.09) eV. Instead, the significantly lower effective barrier ΦB = (0.31 ± 0.01) eV and a temperature‐dependent ideality factor for MoS2/n+ SiC junctions is explained by thermionic‐field‐emission through the thin depletion region of n+ doped SiC. The scalability of PLD MoS2 deposition and the electronic transport tunability by implantation doping of SiC represents key steps for industrial development of MoS2/SiC devices. [ABSTRACT FROM AUTHOR]

Developing effective strategies to improve the initial Coulombic efficiency (ICE) and cycling stability of hard carbon (HC) anodes for sodium‐ion batteries is the key to promoting the commercial application of HC. In this paper, homotype heterojunctions are designed on HC to induce the generation of stable solid electrolyte interfaces, which can effectively increase the ICE of HC from 64.7% to 81.1%. The results show that using a simple surface engineering strategy to construct a homotypic amorphous Al2O3 layer on the HC could shield the active sites, and further inhibit electrolyte decomposition and side effects occurrence. Particularly, due to the suppression of continuous decomposition of NaPF6 in ester‐based electrolytes, the accumulation of NaF could be reduced, leading to the formation of thinner and denser solid electrolyte interface films and a decrease in the interface resistance. The HC anode can not only improve the ICE but elevate its sodium storage performance based on this homotype heterojunction composed of HC and Al2O3. The optimized HC anode exhibits an outstanding reversible capacity of 321.5 mAh g−1 at 50 mA g−1. The cycling stability is also improved effectively, and the capacity retention rate is 86.9% after 2000 cycles at 1 A g−1 while that of the untreated HC is only 52.6%. More importantly, the improved sodium storage behaviors are explained by electrochemical kinetic analysis. [ABSTRACT FROM AUTHOR]

Photovoltaic devices based on ferroelectric materials have broad application prospects; however, there are also problems of narrow bandwidth and low sensitivity. In this paper, polycrystalline BiFeO3 (BFO) films are prepared directly on n‐Si (100) substrates to form ferroelectric/semiconductor heterostructures, the electrical response of which under weak light intensity (0.8 W m−2) is systematically investigated. Accompanied by the dielectric relaxation originated from photocarriers, the polarization of BFO increases while the coercive voltage decreases. Especially, current–voltage (I–V) curve under negative bias voltage changes obviously with illumination, and cyclically switchable photocurrent is detected at 0 V bias, with the on‐off ratio increasing for lower temperature. Although the photoresponse is detectable in the broad wavelength range of 275–1100 nm, it is more pronounced for visible light. It is considered that the built‐in electric field of the PN junction at the BFO/n‐Si interface drives the separation and migration of photocarriers, which in turn affects the interface barrier and the distribution of monovalent oxygen vacancies (VO•$V_{\rm{O}}^ \bullet $) in BFO while producing the photovoltaic effect. This work provides an effective route for developing photodetectors with high sensitivity and broadband detection. [ABSTRACT FROM AUTHOR]

Broadband photodetectors have a wide range of applications in the fields of biomedical sensing, environmental monitoring, optical communications, and space exploration. Since light absorbed by MAPbX3 perovskite materials is mainly located within the visible light region, the detection range of perovskite photodetectors is limited. To broaden the detection range for these types of photodetectors and, thus, enhance the number of possible application scenarios, a non‐fullerene acceptor Y6 is introduced that strongly absorbs light in the near‐infrared band and alongside PM6 forms an organic bulk heterojunction. This results in the expansion of the absorption range due to the formation of a supplementary absorption layer onto the perovskite layer. In this paper, the effects of the newly introduced organic layer on the device performance are studied. Through the synergistic effects of the perovskite and the organic layer, a high‐performance self‐powered perovskite/organic hybrid broadband photodetector can be realized, which contains a wide detection range from ultraviolet and visible light to near‐infrared (300–1000 nm). After its optimization, the device exhibits a high external quantum efficiency value that is as high as 80% in the visible–near‐infrared band, a short response time in the region of 803/698 ns, and a large linear dynamic range of 143 dB. [ABSTRACT FROM AUTHOR]

The heterojunction structure photocatalysts are very promising for photocatalytic degradation dyes to resolve the organic industrial wastewater. In this work, an effective and solar light‐driven Z‐scheme heterojunction photocatalyst CAS/ZnO was prepared by two steps microwave irradiation method. The ZnO nanosheets were successfully compounded with CAS tetragonal particles aggregate. As the ZnO concentration increased, the absorbance decreased but the specific surface area increased. Rhodamine B (RhB) was tested for photodegradation by photocatalysts under a solar simulation in 120 min, and 3 M displayed the highest degradation rate (100 %), highest rate constant (0.021 min−1) and optimum stability. Furthermore, the main reactive species were superoxide radicals (O2−.) and hydroxyl radicals (HO⋅). Also, mechanism of the Z‐scheme migration of photon‐generated carrier and photocatalytic degradation was proposed. This paper provides a new Z‐scheme heterojunction CAS/ZnO photocatalyst for the treatment of organic pollutants. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) presents a promising approach for producing valuable chemicals and fuels, offering a dual benefit in terms of environmental preservation and the efficient utilization of carbon resources. In this work, we proposed a stepwise electrodeposition method to prepare Cu−Pb bimetallic heterojunction catalyst on polyaniline‐modified carbon paper (PANI‐CuPb‐x), where x is the electrodeposition times(min). Among the studied catalysts, the electrode electrodeposited for 2 min (PANI‐CuPb‐2) exhibited a remarkable performance during the electrocatalysis CO2 to multicarbon (C2+) products process, achieving a Faraday efficiency (FE) of 81.46 % and a partial current density of 15.41 mA cm−2 at −1.2 V (vs. RHE) in an H‐type cell. The detailed study demonstrated that introducing Pb could effectively improve the formation of COOH*inhibit hydrogen evolution reaction (HER). Furthermore, the heterojunction structure in the catalysts facilitated C−C coupling of the generated C1 intermediate species, which enhanced the CO2 to C2+ reaction. [ABSTRACT FROM AUTHOR]

In this paper, we used the liquid phase stripping method to manufacture MoS2–SnSe2 heterojunction saturable absorber (SA). The scanning electron microscope, the atomic force microscope, and the Raman spectrometer were used to characterize the MoS2–SnSe2 heterojunction SA. The Q‐switched mode‐locked (QSML) Nd:GGG laser with MoS2–SnSe2 heterojunction SA was presented. The maximum output power of the QSML Nd:GGG laser was 236.4 mW with a repetition rate of 83.3 MHz and pulse width of 447 ps. In short, the MoS2–SnSe2 heterojunction nanosheets present excellent saturable absorption characteristics. [ABSTRACT FROM AUTHOR]

PbSe has attracted wide attention owing to its fascinating physical and chemical properties. It has important technical significance for infrared detectors. However, due to the inherent bandgap, low carrier mobility, and dielectric constant of PbSe, it is a significant challenge to realize fast response and mid‐infrared (MID) photodetection. Chemical doping is an efficient method to regulate the band structure and carrier mobility of materials. Nevertheless, the doped film detector cannot satisfy the demands of high‐performance photodetectors. In this paper, different composition ratios powders are synthesized by a solid‐state method. The PbSe0.5Te0.5 alloy film displays narrower bandgap, higher carrier mobility, excellent photo‐response, and broadband detection capacity. By utilizing the above superiority of PbSe0.5Te0.5 and fast charge transfer in MoSe2, a PbSe0.5Te0.5/MoSe2 p‐n heterostructure device is successfully fabricated that has significant rectifying effect (103) and extremely low dark current density (720 µA cm−2). The photodetector has a maximum responsivity (R) and specific detectivity (D*) of 17.5 A W−1 and 3.08 × 1013 Jones at 780 nm. In addition, the detector displays superior photodetection performance with broadband photodetection (405–5000 nm), high switch ratios (Ion/Ioff = 105), and fast response speed. The above outstanding properties indicate that the PbSe0.5Te0.5/MoSe2 heterostructure provides a promising and efficient strategy for achieving a miniaturized, broadband, and high‐performance photodetector. [ABSTRACT FROM AUTHOR]

Infinite coordination‐polymer particles (CPPs) are promising materials for solar energy conversion with high efficiency. However, the range of organic ligands that may be used to create CPPs is limited, as are strategies for modification, thereby hindering the applications of such material. In this paper, competitive evolution–morphological and structural change from Zn‐based crystallites to amorphous particles is described. Controlled contribution of organic linkers selectively derived six Zn‐CPPs with multivariate characters. Based on the diversity of these substructures, hollow zinc oxide particles were initially formed by self‐pyrolysis of CPPs and effectively modified by ultrathin doped nanosheets. The obtained double‐sided heterojunctions offer fully‐covered active sites, bringing together efficient light‐excited charge‐transfer nanochannels, which exhibit an excellent solar H2‐releasing activity (e.g. 4512.5 μmol h−1 g−1) and stable cyclability. [ABSTRACT FROM AUTHOR]

Fire accidents caused by coal spontaneous combustion seriously affect the production safety of coal mines. Carbon monoxide (CO) is an important gas indicator used for monitoring and early warning detection of coal spontaneous combustion. Therefore, the development of CO sensors with low cost, low power consumption, and environmental protection is highly desirable. This can be achieved through deep optimization of semiconductor CO sensors as alternatives to infrared detection and electrochemical sensors. In this paper, Ti3AlC2 (MXenes)/polyaniline (PANI) composite were studied as semiconductor CO sensors. The optimal added amount of Ti3AlC2 was determined by testing at gas concentrations of 100 ppm and 150 ppm CO. The morphology, structure, and chemical characteristics of each composite were analyzed by field emission transmission electron microscopy (SEM‐EDS), Fourier infrared spectrometry, UV‐visible near infrared spectrophotometer, X‐ray photoelectron spectroscopy (XPS), and thermogravimetric techniques. Compared to pure PANI material, the SEM‐EDS experimental results showed Ti3AlC2 with an increased number of PANI flake structures, generating more CO gas adsorption sites. The XPS results showed Ti3AlC2 was able of improving the protonation and oxidation degree of PANI, thereby improving its gas sensing performance. Accordingly, a sensing mechanism model was proposed, revealing the excellent sensing performance originating from the gas sensing enhancement effect of heterojunction. In sum, this study provided a scientific basis for the design and development of CO sensors with low cost, low power consumption, and future environmental protection. [ABSTRACT FROM AUTHOR]

Ferroelectric materials have been a focus of much research over the last few decades for their unique piezoelectric and optoelectronic properties. Conventional solar cells have been devised based on the photovoltaic effect of semiconductor p–n junctions, with their photogenerated voltage being influenced by the bandgap of the semiconductors, limiting their further development. Ferroelectric photovoltaics have attracted attention for their unusual photovoltaic effect and controllability. The photogenerated voltage that is independent of bandgap along the polarization direction can be generated in ferroelectric materials, undoubtedly making up for the lack of solar cells. Ferroelectric materials have been used in a wide range of piezoelectric, storage, sensor, and optoelectronic because of their unique optical and electrical properties. However, the small photogenerated current of ferroelectric photovoltaic devices is one of the challenges that need to be overcome. Researchers have shown that the photogenerated current of ferroelectric photovoltaic devices can be significantly improved by cation doping and heterostructure construction, reigniting the enthusiasm for the investigation of ferroelectric photovoltaics. This paper reviews a variety of ferroelectric photovoltaic materials, the mechanism of ferroelectric photovoltaics, approaches for improving ferroelectric photovoltaic performance, and the applications and future prospects for ferroelectric materials. [ABSTRACT FROM AUTHOR]

There has been a growing interest in electronic and optoelectronic devices based on heterostructures between atomically thin 2D and 3D semiconductor materials. This paper proposes a 2D molybdenum disulfide (MoS2)/3D germanium (Ge) junction field‐effect transistor (JFET). Typical electrical characteristics of the JFET are observed, with a low subthreshold swing of ≈88 mV/dec and a high on/off ratio of ≈105. The device exhibits a bidirection photoresponse in which the photocurrent polarity is reversed depending on the wavelength of light. Under visible illumination at 532 nm, the positive photoresponsivity of this device can be modulated by the gate voltage, reaching a peak value of 66 A W−1. In contrast, the device exhibits a tunable negative photoresponse behavior under an infrared illumination of 1550 nm. This is attributed to the competition between the negative photoresponse from the bolometric effect in MoS2 and the positive photoresponse from photogenerated carriers in Ge. Based on these interesting characteristics in this JFET, three controllable current states (−1, 0, and 1) are realized by changing the gate voltage and infrared light. These results indicate that the device has promising potential as a multifunctional optoelectronic unit, including signal amplification, broadband photodetection, and multilogic calculations. [ABSTRACT FROM AUTHOR]

The "shuttle effect" issue severely hinders the practical application of lithium–sulfur (Li–S) batteries, which is primarily caused by the significant accumulation of lithium polysulfides in the electrolyte. Designing effective catalysts is highly desired for enhancing polysulfide conversion to address the above issue. Here, the one‐step flash‐Joule‐heating route is employed to synthesize a W‐W2C heterostructure on the graphene substrate (W‐W2C/G) as a catalytic interlayer for this purpose. Theoretical calculations reveal that the work function difference between W (5.08 eV) and W2C (6.31 eV) induces an internal electric field at the heterostructure interface, accelerating the movement of electrons and ions, thus promoting the sulfur reduction reaction (SRR) process. The high catalytic activity is also confirmed by the reduced activation energy and suppressed polysulfide shuttling by in situ Raman analyses. With the W‐W2C/G interlayer, the Li–S batteries exhibit an outstanding rate performance (665 mAh g−1 at 5.0 C) and cycle steadily with a low decay rate of 0.06% over 1000 cycles at a high rate of 3.0 C. Moreover, a high areal capacity of 10.9 mAh cm−2 (1381.4 mAh g−1) is obtained with a high area sulfur loading of 7.9 mg cm−2 but a low electrolyte/sulfur ratio of 9.0 µL mg−1. [ABSTRACT FROM AUTHOR]

Due to their inherent lattice mismatch characteristics, 2D heterostructure interfaces are considered ideal for achieving stable and sustained ultralow friction (superlubricity). Despite extensive research, the current understanding of how interface adhesion affects interlayer friction remains limited. This study focused on graphene/MoS2 and graphene/PdSe2 heterostructure interfaces, where extremely low friction coefficients of ≈10−3 are observed. In contrast, the MoS2/PdSe2 heterostructure interfaces exhibit higher friction coefficients, ≈0.02, primarily due to significant interfacial interactions driven by interlayer charge transfer, which is closely related to the ionic nature of 2D material crystals. These findings indicate that the greater the difference in ionicity between the two 2D materials comprising the sliding interfaces is, the lower the interlayer friction, providing key criteria for designing ultralow friction pairs. Moreover, the experimental results demonstrate that interlayer friction in heterostructure systems is closely associated with the material thickness and interface adhesion strength. These experimental findings are supported by molecular dynamics simulations, further validating the observed friction behavior. By integrating experimental observations with simulation analyses, this study reveals the pivotal role of interface adhesion in regulating interlayer friction and offers new insights into understanding and optimizing the frictional performance of layered solid lubricants. [ABSTRACT FROM AUTHOR]

The development of efficient and durable non‐precious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is highly desirable but challenging. Amorphous‐crystalline (A‐C) heterostructures have garnered attention due to their unusual atomic arrangements at hetero‐interfaces, highly exposed active sites, and excellent stability. Here, a heterogeneous synthesis strategy for constructing A‐C non‐homogeneous interfacial centers of electrocatalysts on nanocages is presented. Isolated PdCo clusters on nanoscale islands in conjunction with Co3S4 A‐C, functioning as a bifunctional site "island‐sea" synergy, enable the dynamic confinement design of metal active atoms, resulting in excellent HER catalytic activity and durability. The hierarchical structure of hollow porous nanocages and nanoclusters, along with their large surface area and multi‐dimensional A‐C boundaries and defects, provides the catalyst with abundant active centers. Theoretical calculations demonstrate that the combination of PdCo and Co3S4 regulates the redistribution of interface electrons effectively, promoting the sluggish water‐dissociation kinetics at the cluster Co sites. Additionally, PdCo‐Co3S4 heterostructure nanocages exhibit outstanding HER activity in alkaline seawater and long‐term stability for 100 h, which can be powered by commercial silicon solar cells. This finding significantly advances the development of alkaline seawater electrolysis for large‐scale hydrogen production. [ABSTRACT FROM AUTHOR]

Mix‐dimensional heterojunctions (MDHJs) photodetectors (PDs) built from bulk and 2D materials are the research focus to develop hetero‐integrated and multifunctional optoelectronic sensor systems. However, it is still an open issue for achieving multiple effects synergistic characteristics to boost sensitivity and enrich the prospect in artificial bionic systems. Herein, electrically tunable Te/WSe2 MDHJs phototransistors are constructed, and an ultralow dark current below 0.1 pA and a large on/off rectification ratio of 106 is achieved. Photoconductive, photovoltaic, and photo‐thermoelectric conversions are simultaneously demonstrated by tuning the gate and bias. By these synergistic effects, responsivity and detectivity respectively reach 13.9 A W−1 and 1.37 × 1012 Jones with 400 times increment. The Te/WSe2 MDHJs PDs can function as artificial bionic visual systems due to the comparable response time to those of the human visual system and the presence of transient positive and negative response signals. This work offers an available strategy for intelligent optoelectronic devices with hetero‐integration and multifunctions. [ABSTRACT FROM AUTHOR]

A method for patterning single‐layer graphene (SLG) and single‐layer oxidized graphene (SOG) within a continuous atomic layer to form lateral heterojunctions is presented. Raman spectroscopy is employed to investigate the evolution of defect‐related Raman peaks during excimer‐UV irradiation, facilitating the identification of structural changes and defect formation processes. Electrical transport measurements reveal that SOG‐patterned field‐effect transistors (FETs) exhibit varying characteristics depending on the degree of oxidation, thus offering the potential to tailor the electrical properties of graphene devices for specific requirements. Scanning Kelvin probe microscopy measurements reveal the surface potential and work function of the SOG regions compared with those of SLG. The effective functionality of the SOG pattern to operate as a resistor, allowing control of the electrical conductivity in the SOG‐patterned SLG channels, is demonstrated. This capability restricts the current flow while preserving the pristine electrical properties of the graphene channel. Moreover, the SOG pattern can serve as a potential barrier to constructing SLG‐SOG‐patterned integrated circuits, providing exciting opportunities for engineering advanced electronic components. This breakthrough in graphene devices simplifies the fabrication process of graphene‐based FETs and provides the foundation for developing atomically thin integrated circuits for a wide range of applications. [ABSTRACT FROM AUTHOR]

The article presents the discussion on utilisation of Solar energy which being the most important renewable energy on Earth. Topics include photocatalysis utilizing solar energy for decomposing water to produce hydrogen, reducing carbon dioxide for synthesizing solar fuel, and degrading pollutants to purify the environment; and intramolecular migration of electrons and hole leading to enhanced photocatalytic hydrogen evolution.

In the field of photocatalysis, building a heterojunction is an effective way to promote electron transfer and enhance the reducibility of electrons. Herein, the S‐scheme heterojunction photocatalyst (CoS2/Zn0.5Cd0.5S) of CoS2 nanospheres modified Zn0.5Cd0.5S solid solution was synthesized and studied. The H2 evolution rate of the composite catalyst reached 25.15 mmol g−1 h−1, which was 3.26 times that of single Zn0.5Cd0.5S, whereas pure CoS2 showed almost no hydrogen production activity. Moreover, CoS2/Zn0.5Cd0.5S had excellent stability and the hydrogen production rate after six cycles of experiments only dropped by 6.19 %. In addition, photoluminescence spectroscopy and photoelectrochemical experiments had effectively proved that the photogenerated carrier transfer rate of CoS2/Zn0.5Cd0.5S was better than CoS2 or Zn0.5Cd0.5S single catalyst. In this study, the synthesized CoS2 and Zn0.5Cd0.5S were both n‐type semiconductors. After close contact, they followed an S‐scheme heterojunction electron transfer mechanism, which not only promoted the separation of their respective holes and electrons, but also retained a stronger reduction potential, thus promoting the reduction of H+ protons in photocatalytic experiments. In short, this work provided a new basis for the construction of S‐scheme heterojunction in addition to being used for photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Photocatalytic Z or S scheme merits higher redox potentials and faster charge separation. However, heterostructure photocatalysts with band gaps of bulk materials often have a type I band structure leading to poor photocatalytic activity. In view of this, we report simultaneous tuning of band gaps of Cu2O and TiO2, where quantum dot Cu2O nanoparticles were formed on doped TiO2 with Ti3+. The reduced size of Cu2O made its conduction band more negative, whereas the introduction of Ti3+ made the absorption edge red shift to the visible light region. The as‐formed heterostructure enabled an S‐Scheme mechanism with remarkable activity and stability for visible light photodegradation of 4‐chlorophenol (4‐CP). The as‐obtained photocatalysts' activity demonstrated ca. 510‐fold increase as compared to individual ones and a mechanical blend. The as‐obtained photocatalysts maintained over 80 % for 5 cycles and 2 months exposure to O2 did not decrease the degradation rate. ESR characterization and scavenger experiments proved the S‐Scheme mechanism. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution is a promising method to convert solar energy. Here, the heterojunction structure of g‐C3N4/CdS was modified by NiCoP prepared by one‐step method for the first time, and the photocatalyst NiCoP‐g‐C3N4/CdS was successfully designed and prepared, which can effectively separate and transfer photogenerated electrons and efficient hydrogen evolution under visible light. Moreover, NiCoP‐g‐C3N4/CdS photocatalyst has abundant surface‐active sites, and its photocatalytic hydrogen evolution performance has been greatly improved. When NiCoP content was 5 % in NiCoP‐g‐C3N4/CdS, the catalytic activity was the highest, and the hydrogen production rate reached an astonishing 55.63 mmol h−1 g−1, which was 23.35 times that of CdS (2.38 mmol h−1 g−1) and 11.51 times that of g‐C3N4/CdS (4.84 mmol h−1 g−1). In addition, NiCoP‐g‐C3N4/CdS photocatalyst has excellent stability for hydrogen production. The materials were characterized and analyzed by XRD, SEM, TEM, XPS, UV‐Vis DRS, FTIR, UPS, N2 adsorption‐desorption process and electrochemical test etc. At the same time, the possible mechanism of NiCoP‐g‐C3N4/CdS photocatalytic hydrogen production reaction is proposed. This study provides a new idea for the rational design of heterojunction photocatalyst and transition metal phosphide cocatalyst. [ABSTRACT FROM AUTHOR]

The influence of N‐substituents on the photovoltaic properties of singly bay‐linked perylene diimides (diPDIs) was systematically investigated to understand the aromatic‐aliphatic balance, which is beneficial for achieving high device performance in organic photovoltaic (OPV) systems. The synthesis of various N‐substituted diPDIs was successfully achieved using a newly developed one‐step procedure, resulting in sufficiently high yields. Detailed investigations of seven variants of diPDIs demonstrated that the primary alkyl substituents, particularly the 2‐ethylhexyl group, induce the self‐organized growth of thin films with high crystallinity. This is beneficial for enhancing the device performance of bulk heterojunction (BHJ) systems. The results presented herein reveal the important roles of alkyl side chains as hydrophobic solubilizing auxiliaries or primary determinants in the control of the active layer nanomorphology. This offers a valuable guideline that is essential for developing high‐performance organic semiconductor materials for future practical applications. [ABSTRACT FROM AUTHOR]

To promote the utilization efficiency of solar energy, a one‐step strategy to fabricate 2D/2D Z‐scheme BiOCl/g‐C3N4 nanosheets (BiOCl/CNs) heterojunction through the in‐situ growth of BiOCl on CNs was studied. Here, we report that ultrathin CNs with wrinkled surface are prepared by a rapid cooling method. The wrinkled surface of CNs provided more active sites for BiOCl to anchor on it thus facilitating the formation of the tight heterojunction structure via a solvothermal process. The as‐prepared BiOCl/CNs hybrid photocatalysts was confirmed by various physicochemical characterizations. The results showed the uniform distribution of BiOCl nanoflakes on g‐C3N4 nanosheets and formation of 2D/2D Z‐scheme heterojunction structure. The as‐prepared BiOCl/CNs‐5 photocatalyst displays extraordinarily photocatalytic activity for the photocatalytic degradation of RhB and Cr(VI) reduction under visible light irradiation, about 94 % RhB and 93 % Cr(VI) was degraded in 100 min. The remarkable photocatalytic properties were attributed to the Z‐scheme hierarchical structure, large specific surface and efficient charge carrier separation. Furthermore, the Z‐scheme photocatalytic reaction mechanism was presented to elucidate the improved photocatalytic activity of BiOCl/CNs photocatalyst. The photodegradation of phenol and radical species trapping experiments were conducted to prove the formation of Z‐scheme. This work provides a facile route for the construction of g‐C3N4 based Z‐scheme structure photocatalyst for efficient visible light photocatalytic performance. [ABSTRACT FROM AUTHOR]

Re‐extracting environmentally transportable hexavalent uranium from wastewater produced by spent fuel reprocessing using the photocatalytic technology is a crucial strategy to avoid uranium pollution and recover nuclear fuel strategic resources. Here, we have designed S‐scheme 2D/0D C3N5/Fe2O3 heterojunction photocatalysts based on the built‐in electric field and the energy band bending theory, and have further revealed the immobilization process of hexavalent uranium conversion into relatively insoluble tetravalent uranium in terms of thermodynamics and kinetics. According to the results, the hexavalent uranium removal and recovery ratios in wastewater are as high as 93.38% and 83.58%, respectively. Besides, C3N5/Fe2O3 heterojunctions also exhibit satisfactory catalytic activity and selectivity even in the presence of excessive impurity cations (including Na+, K+, Ca2+, Mg2+, Sr2+, and Eu3+) or various organics (such as xylene, tributylphosphate, pyridine, tannic acid, citric acid, and oxalic acid). It is believed that this work can provide a potential opportunity for S‐scheme heterojunction photocatalysts to re‐enrich uranium from spent fuel wastewater. [ABSTRACT FROM AUTHOR]

Energy conversion and storage integrated power units suffer from multiple engineering issues. Replacing two devices (solar cell and supercapacitor assembly) with one device (photo‐enhanced supercapacitor‐ PSC) requires materials with emerged dual solar‐electrochemical storage attributes. Herein, a propitious approach is developed to fabricate all visible light‐enhanced semisolid flexible PCS. Nanoflakes‐based p‐n junction α‐(Fe2O3)1‐x(Cr2O3)x photocathode is synthesized directly on industrial waste stainless steel mesh (316L‐SS). Alongside, three TiO2‐based electrodes are utilized as positive photoactive electrodes. Tuning the optical properties of TiO2 is displayed via doping with mixed valence vanadium (V4+/V5+) together with thermal hydrogen annealing. This is revealed via the reduction of the bandgap energy from 2.89 to 2.15 eV, which can be ascribed to the induced oxygen vacancies. The device can sustain up to 1.6 V potential window with 91% stability after 350 successive charge/discharge cycles with the possibility of performance regeneration to its 100% retention. An illustration of the photo‐storage mechanism is proposed based on the X–ray photoelectron spectroscopy, X–ray crystallography, and band position/alignment results. Quasi‐reversible water splitting/formation is concluded as the main storage mechanism in the semisolid state electrolyte under illumination conditions. [ABSTRACT FROM AUTHOR]

Addressing the escalating concerns over increasing carbon dioxide (CO2) emissions and their detrimental effect on the environment has become global attention. One promising alternative to tackle this issue involves utilizing photocatalytic technology to convert CO2 into more valuable chemicals, with methane (CH4) being a notable targeted product. This article presents a comprehensive review of the exploration of TiO2‐based photocatalysts by researchers worldwide for such applications. The initial discussion revolves around fundamental aspects, including the basic principles, thermodynamics, kinetics, and reaction mechanisms involved in the process. Additionally, to enhance the efficiency of these aspects, support from other factors is necessary, including the physicochemical properties of the photocatalyst through various catalyst synthesis methods (such as sol‐gel, precipitation, hydrothermal, and solvothermal) as well as employing catalyst modification techniques (such as doping, heterojunction, and surface modifications). Furthermore, the review delves into an examination of parameters that influence the photocatalytic CO2 reduction to methane process, as they directly impact the yield and selectivity of the desired product. Ultimately, the existing challenges and potential research opportunities that could provide comprehensive solutions for the applications of photocatalytic technology for converting CO2 to CH4 as a whole are elaborated in this review. [ABSTRACT FROM AUTHOR]

As emphasized in a recent review article (Chem. Rev. 2022, 122, 14180), organic solar cell (OSC) photoconversion efficiency has been rapidly evolving with results increasingly comparable to those of traditional inorganic solar cells. Historically, OSC performance improvement focused first on the morphology of P3HT:PC61BM solar cells then went through different stages to shift lately interest towards nonfullerene acceptors (NFAs) as a replacement of PC61BM acceptor (ACC) molecule. Here, we use density‐functional theory (DFT) and time‐dependent DFT to investigate four novel NFAs of A‐D‐A (acceptor‐donor‐acceptor) form derived from the recently synthesized IDIC‐4Cl (Dyes Pigm. 2019, 166, 196). Our level of theory is carefully evaluated for IDIC‐4Cl and then applied to the four novel NFAs in order to understand how chemical modifications lead to physical changes in cyclic voltammetry (CV) frontier molecular orbital energies and absorption spectra in solution. Finally we design and apply a new type of Scharber plot for NFAs based upon some simple but we think reasonable assumptions. Unlike the original Scharber plots where a larger DON band gap favors a larger PCE, our modified Scharber plot reflects the fact that a smaller ACC band gap may favor PCE by filling in gaps in the DON acceptor spectrum. We predict that only the candidate molecule with the least good acceptor A, with the highest frontier molecular orbital energies, and one of the larger CV lowest unoccupied molecular orbital (LUMO) − highest unoccupied molecular orbital (HOMO) gaps, will yield a PM6:ACC PCE exceeding that of the parent IDIC‐4Cl ACC. This candidate also shows the largest oscillator strength for the primary 1(HOMO, LUMO) charge‐ transfer transition and the largest degree of delocalization of charge transfer of any of the ACC molecules investigated here. [ABSTRACT FROM AUTHOR]

Due to their environmental friendliness, low cost, and versatility in applications, flexible Cu2ZnSn(S, Se)4 (CZTSSe) solar cells have garnered significant attention in recent years. However, the lack of alkali metal elements in the flexible substrate has posed a challenge to the advancement of flexible CZTSSe solar cells. In this study, a post‐treatment strategy is proposed involving Rb ions to simultaneously regulate the surface properties of the CZTSSe film and the reactions during the CdS chemical bath deposition (CBD) process. Material and chemical characterization results confirm that Rb ions effectively passivate the detrimental Se0 defect, leading to a more active surface for the CdS epitaxial growth. Additionally, the coordination between Rb ions and thiourea in the CBD solution improves the ion‐by‐ion deposition of the CdS layer. These beneficial effects significantly improve the heterojunction interface and consequently enable the flexible CZTSSe solar cell to achieve a record total‐area efficiency of 12.84% and excellent bending performance. Overall, the heterojunction interface regulation strategy employed in this work, along with the obtained remarkable results, offer promising prospects for the development of flexible CZTSSe solar cells. [ABSTRACT FROM AUTHOR]

Photocatalytic reactions for fuel generation are crucial for the world's energy needs. Covalent‐Organic‐Frameworks (COFs) have been extensively studied as promising designable photocatalysts for these reactions due to their efficient visible‐light absorption, suitable energy‐band structure, facilitated intramolecular charge separation, and fast mass transfer. However, the activities of pristine COFs remain unsatisfactory, due to intermolecular charge recombination. Recently, COF‐based heterostructures, which combine COFs with metal‐sulfides, metal‐oxides, carbon materials, or MOFs, have attracted increasing attention for enhancing solar‐to‐fuel conversion efficiency by facilitating interfacial photo‐generated carrier separation, sensitizing wide‐gap semiconductors, and promoting surface redox reactions. Thus, a review of the state‐of‐the‐art progress of COF‐based heterostructure photocatalysts in reactions such as H2 evolution, CO2 reduction, O2 evolution, H2O splitting and CO2 splitting is crucial for the design of new photocatalysts to promote solar‐to‐fuel conversion. In this review, the COF‐based heterostructures photocatalysts are highlighted based on their synthesis, properties, and reasons for enhanced activities. Moreover, design principles are raised for such photocatalysts for each fuel generation reaction, based on insights into related research. Finally, this review is concluded by proposing future trends for COF‐based heterostructures photocatalysts, with attention to the design of COFs and supports, analyzing the photocatalytic reaction dynamics, together with considering practical applications. [ABSTRACT FROM AUTHOR]

The metal‒semiconductor heterojunction is imperative for the realization of electrically driven nanolasers for chip‐level platforms. Progress in developing such nanolasers has hitherto rarely been realized, however, because of their complexity in heterojunction fabrication and the need to use noble metals that are incompatible with microelectronic manufacturing. Most plasmonic nanolasers lase either above a high threshold (101‒103 MW cm−2) or at a cryogenic temperature, and lasing is possible only after they are removed from the substrate to avoid the large ohmic loss and the low modal reflectivity, making monolithic fabrication impossible. Here, for the first time, record‐low‐threshold, room‐temperature ultraviolet (UV) lasing of plasmon‐coupled core‒shell nanowires that are directly grown on silicon is demonstrated. The naturally formed core‒shell metal‒semiconductor heterostructure of the nanowires leads to a 100‐fold improvement in growth density over previous results. This unprecedentedly high nanowire density creates intense plasmonic resonance, which is outcoupled to the resonant Fabry‒Pérot microcavity. By boosting the emission strength by a factor of 100, the hybrid photonic‒plasmonic system successfully facilitates a record‐low laser threshold of 12 kW cm−2 with a spontaneous emission coupling factor as high as ≈0.32 in the 340‒360 nm range. Such architecture is simple and cost‐competitive for future UV sources in silicon integration. [ABSTRACT FROM AUTHOR]

Metal halide perovskite solar cells (PSCs) have become one of the most promising next‐generation photovoltaic technologies due to their low‐cost fabrication, solution processability, and superior optoelectronic properties. Although state‐of‐art PSCs demonstrate a power conversion efficiency record comparable to that of silicon solar cells, there are still many challenges toward commercialization. PSCs are devices based on various semiconductor heterojunctions that all play important roles in device performance. The device operation relies on a combination of multiple heterojunctions to offer a delicate control of photocarrier generation, separation, and transport to respective electrodes. Hence, advanced heterojunction design in PSCs is crucial for the further improvement of device performance. Notably, the conversion efficiency records for PSCs are mainly ascribed to optimized heterojunction engineering. Considering the significance of this topic, a comprehensive review of the recently developed heterojunction designs is presented. Following a brief introduction to PSC architectures, operation, and fundamental heterojunction design theories, the recent progress on perovskite/electron transport layer, perovskite/hole transport layer, and perovskite/perovskite heterojunction engineering is elaborated. Finally, conclusions and perspectives on this research field are addressed. [ABSTRACT FROM AUTHOR]

Constructing and manipulating hetero‐interfaces for the electrocatalytic hydrogen evolution reaction (HER) is highly desirable, but still poses a significant challenge. Herein, this work adopts a facile way to controllably synthesize three different hetero‐interfaces by anchoring ultrafine Ru nanoparticles on various MoOx nanotube (NT) substrates, including MoO2, MoO2/MoO3, and MoO3. Remarkably, MoO2@Ru NT displays excellent HER activity with tiny overpotentials of 89 and 131 mV delivering large current densities of 500 and 1000 mA cm−2, respectively, far surpassing two other hetero‐interfaces, commercial Ru/C, Pt/C catalysts. Impressively, this hetero‐interface even achieves an exceptionally large current density of 4000 mA cm−2 at an overpotential of 322 mV. Moreover, MoO2@Ru NT presents exceptional stability for at least 100 h at 1000 mA cm−2 with negligible degradation. Both experimental observations and theoretical calculations suggest that moderate electron transfer from Ru to MoO2 enhances the water dissociation kinetics, and optimizes the hydrogen adsorption/desorption, thus simultaneously speeding up the HER kinetics. Furthermore, an anion exchange membrane electrolyzer assembled by obtained MoO2@Ru NT as a cathode electrocatalyst, shows attractive activity and excellent durability, with a low voltage of 1.78 V at 1000 mA cm−2, and a prolonged time period for 200 h at 1000 mA cm−2. [ABSTRACT FROM AUTHOR]

The tribovoltaic effect can convert semiconductor interfacial frictional mechanical energy into direct current (DC) electricity, but the flexibility and durability of semiconductor materials limit its application in wearable electronic. Herein, a robust flexible textile tribovoltaic nanogenerator is presented based on a 2D dynamic heterojunction of 2H‐MoS2/Ta4C3 (MTNG). During the friction process, a built‐in electric field (Eb) and an additional interfacial electric field (ECE) are generated in a continuous dynamic contact of 2H‐MoS2/Ta4C3, and through the 2H‐MoS2/Ta4C3 dynamic heterojunction, a significant number of electron‐hole pairs are excited and move directionally to generate a DC. The influences of mechanical pressure and sliding speed on output performance of MTNGs are systematically investigated. The MTNGs deliver excellent output power density (39.15 mW m2) and outstanding robustness (43 000 cycles). Ten MTNGs can be connected in series to obtain a DC voltage of 3.3 V and in parallel to obtain a DC current of 75 µA. Furthermore, the MTNGs can effectively power a variety of commercial electronic watches and calculators by harvesting human kinetic energy. A 2D dynamic heterojunction 2H‐MoS2/Ta4C3 DC nanogenerator is described and offers a workable option for the creation of flexible DC power sources and self‐powered wearable electronics. [ABSTRACT FROM AUTHOR]

g‐C3N5 has wide‐ranging applications in photocatalysis owing to its two‐dimensional layered structure, large surface area, and small band gap. In this study, the surface of g‐C3N5 was subjected to inorganic acid modification and combined with BiOCl to form a heterojunction, effectively improving the photocatalytic activity of the material. The rates of degradation of rhodamine B and ciprofloxacin by the 15‐C3N5‐BiOCl composite photocatalyst were 22.2 and 20.7 times higher, respectively, than those of degradation by g‐C3N5. This was attributed to the Z‐type heterojunction formed by g‐C3N5 and BiOCl, which significantly improved the efficiency of photogenerated electron–hole pairs separation and broadened the optical response range. The preparation of novel photocatalysts has broad application prospects in the treatment of organic pollutants in water. [ABSTRACT FROM AUTHOR]