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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]

Solar-driven water splitting by inorganic semiconductor photocatalysts is considered a promising method to produce hydrogen fuel. Loading inorganic semiconductor on cellulose fiber to construct photocatalytic paper contributes to the dispersion and recycling of photocatalyst. In addition, the photocatalytic paper floating on water can build a solid–gas biphase photocatalytic interface (photothermal-generated steam/photocatalytic paper/hydrogen), replacing the traditional liquid–solid–gas triphase photocatalytic interface (liquid water/photocatalyst/hydrogen) for improving photocatalytic kinetics. Here, we design and synthesize a photocatalytic composite paper with zinc sulfide (ZnS) anchored onto cellulose fibers (CF) with the help of polydopamine (PDA). PDA achieves high load and uniform distribution of ZnS on cellulose fibers, and forms the ZnS/PDA heterojunction to increase photogenerated charge separation efficiency and photocatalytic stability. Solid–gas biphase photocatalytic interface constructed by the CF/PDA/ZnS composite paper minimizes the interface barriers of hydrogen transport and water molecular adsorption for improving hydrogen evolution rate. The CF/PDA/ZnS composite paper shows a high hydrogen production rate up to 18706.8 μmol h−1 g−1. Stable loading of ZnS/PDA heterojunction in composite paper contributes to the photocatalytic stability. In the third photocatalytic cycle, the hydrogen evolution rate of CF/PDA/ZnS composite paper remains 96.4%. This work inspires that anchoring of inorganic semiconductor on cellulose fibers with the help of PDA can be a promising strategy for designing efficient photocatalytic paper for solar hydrogen production. [ABSTRACT FROM AUTHOR]

• MoS 2 /Bi 2 S 3 heterojunction photodetectors were prepared on nylon paper substrates. • The performance is different when the photodetectors are prepared in different order. • The devices exhibit good photoresponse in the range of 365 nm-980 nm. • The response time of the MoS 2 /Bi 2 S 3 photodetector is only 53 ms under UV light. • The devices have excellent bendability and stability. Flexible photodetectors are receiving increasing attention due to their promising applications in wearable optoelectronic devices, bendable imaging sensors, and implantable optoelectronic devices. In this work, a novel strategy for constructing flexible photodetectors based on a hybrid heterojunction of Bi 2 S 3 and MoS 2 was proposed. The devices are fabricated on a biodegradable paper substrate using a simple hydrothermal process and vacuum filtration techniques and exhibit a broadband photoresponse from ultraviolet to near-infrared (NIR). Especially, the specific detectivity (D*) of the MoS 2 /Bi 2 S 3 photodetectors is 3.25 × 1010 Jones under 365 nm, and the rise/decay time is 0.053 s/0.119 s in the NIR region. In addition, the performance of Bi 2 S 3 /MoS 2 photodetectors realizes a maximum responsivity (R) of 27.45 mA/W and a fast response time (∼0.470 s). These devices exhibit a stable photoresponse under repeated bending. Inexpensive materials and easy fabrication techniques provide a viable strategy for the design and performance optimization of flexible bimetallic sulfide photodetectors. [Display omitted] [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]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, contains a variety of articles on different topics in chemistry. The articles cover areas such as polydimethylsiloxane coatings, water oxidation, lithium-ion batteries, and photocatalytic reactions. The journal provides valuable insights for those interested in chemistry and covers a diverse range of research areas. The document is a list of research papers published in the journal Chemistry in 2024, including topics such as the electrocatalytic degradation of tetracycline, the construction of a supramolecular system for imaging nematic mesophase and nematode cells, insights into hydrogen bond strengths in microhydrated clusters, and the development of macrophage-red blood cell hybrid membranes for eliminating pathogens, endotoxins, and heavy metal ions from blood. [Extracted from the article]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a list of papers featured in the issue, covering topics such as photocatalytic hydrogen generation, thermal performance of glass coatings, and Zn ion storage performance. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

In this paper, simulation modeling was carried out using Sentaurus Technology Computer-Aided Design. Two types of high electron mobility transistors (HEMT), an AlGaN/GaN/AlGaN double heterojunction and AlGaN/GaN single heterojunction, were designed and compared. The breakdown characteristics and damage mechanisms of the two devices under the injection of high-power microwaves (HPM) were studied. The variation in current density and peak temperature inside the device was analyzed. The effect of Al components at different layers of the device on the breakdown of HEMTs is discussed. The effect and law of the power damage threshold versus pulse width when the device was subjected to HPM signals was verified. It was shown that the GaN HEMT was prone to thermal breakdown below the gate, near the carrier channels. A moderate increase in the Al component can effectively increased the breakdown voltage of the device. Compared with the single heterojunction, the double heterojunction HEMT devices were more sensitive to Al components. The high domain-limiting characteristics effectively inhibited the overflow of channel electrons into the buffer layer, which in turn regulated the current density inside the device and improved the temperature distribution. The leakage current was reduced and the device switching characteristics and breakdown voltage were improved. Moreover, the double heterojunction device had little effect on HPM power damage and high damage resistance. Therefore, a theoretical foundation is proposed in this paper, indicating that double heterojunction devices are more stable compared to single heterojunction devices and are more suitable for applications in aviation equipment operating in high-frequency and high-voltage environments. In addition, double heterojunction GaN devices have higher radiation resistance than SiC devices of the same generation. [ABSTRACT FROM AUTHOR]

In this paper, the geometric configuration, electronic properties, and optical characteristics of an InS/GaTe heterojunction have been computed using the foundational principles of density functional theory. The analysis indicates that when the interlayer distance is 3.88 Å, the binding energy is the most negative, indicating that the structure is the most stable. The bandgap of the two monolayers is larger than that of the heterojunction, which makes the photogenerated electrons of the heterojunction more easily excited. The InS/GaTe heterojunction is a type-II heterojunction that enhances the efficient dissociation of electron–hole pairs. In addition, the InS/GaTe heterojunction demonstrates strong absorption of ultraviolet light, rendering it suitable for applications in ultraviolet detectors and related fields. Furthermore, the bandgap electron transfer direction of the InS/GaTe heterojunction can be controlled by applying electrical force and mechanical pressure. The optical absorption coefficient of the InS/GaTe heterojunction can be adjusted to modify its optical properties. Finally, the possible future applications of the InS/GaTe heterojunction are discussed. [ABSTRACT FROM AUTHOR]

In this paper, a NiAl-LDH with the characteristic structure of a hydrotalc-like compound was applied as a carrier in a two-step hydrothermal process, and a MnCdS/In2S3/NiAl-LDH composite material was successfully prepared by loading MnCdS and In2S3 on the flower spherical-like surface of NiAl-LDH. The combination of NiAl-LDH with In2S3 and MnCdS made the band gap smaller and the light absorption range larger, thus increasing the utilization rate of light. 50% MnCdS/In2S3/NiAl-LDH composites had the best photoinduced charge separation and highest surface enrichment of photogenerated electrons. In the degradation experiment of crystal violet (CV), 50% MnCdS/In2S3/NiAl-LDH composites showed superior photocatalytic degradation efficiency (>98.5%) under full spectrum light. Furthermore, the applicability and universality of photocatalysts were studied by observing the degradation of CV by MnCdS/In2S3/NiAl-LDH composites under different conditions. In addition, the composites showed excellent hydrogen production capacity in the photolysis of water, in which hydrogen production within 8 hours was about 7661.51 μmol g−1. By combining the results of active species capture experiments, density functional theory (DFT) calculations and photoelectrochemical experiments, the possible mechanism of double S-scheme heterojunction photocatalysis among NiAl-LDH, In2S3 and MnCdS was inferred, which is one of the main reasons for the enhancement of photocatalytic activity. [ABSTRACT FROM AUTHOR]

The widespread use of antibiotics leads to the pollution of the water environment. Photocatalytic technology is considered as an effective way of removing antibiotics from the water environment. In this paper, a semi-embedded CdS/tubular g-C3N4 (CdS/TCN) heterojunction photocatalyst was designed and prepared by hydrothermal, in situ oil bath and thermal polymerization methods. Then Ni nanoparticles were loaded onto the surface of CdS/TCN by an in situ photoreduction method to form high performance photocatalyst Ni–CdS/TCN. The degradation rate of tetracycline hydrochloride (TCH) by Ni–CdS/TCN-6 was about 1.9 times higher than that of bulk carbon nitride (BCN) under visible light irradiation for 30 min. The high specific surface area, the effective heterojunction and loaded Ni broaden the light absorption range, narrow the band gap and improve the photogenerated carrier separation efficiency and migration rate. Beyond that, loaded Ni also inhibits photocorrosion and improves the stability of the photocatalyst. The present work provides a new way for designing a semi-embedded heterojunction photocatalyst. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Selectivity improvement by the frequency tuning of Mg@ZnO–TiO2 nanoflake-based heterojunction devices under exposure to different volatile organic compounds is the prime focus of the present paper. The synthesis of Mg@ZnO–TiO2 nanoflakes was carried out using a solution process followed by a low-cost hydrothermal method. A capacitive measurement approach was used to find the resonant frequencies of the device in 2-butanone, acetone, 2-propanol, ethanol, and methanol environments in the frequency range from 0.001 to 220 kHz. A Cole–Cole plot derived from impedance measurements suggested that the device impedance consisted of capacitance (Cz = 2.01 pF and CT = 2.17 pF) and resistance (Rz = 13 552.2 kΩ and RT = 3500.574 kΩ) from the ZnO nanoflake layer and TiO2 thin film layer, respectively. The maximum capacitive responses to 2-butanone (C4H8O), acetone (C3H6O), 2-propanol (C3H8O), ethanol (C2H5OH), and methanol (CH3OH) were recorded at resonant frequencies of 1.000 kHz, 0.791 kHz, 0.702 kHz, 0.319 kHz and 0.103 kHz, respectively, at the corresponding temperature of 125 °C, 100 °C, 100 °C, 75 °C, and 75 °C, respectively. The device offered optimum capacitive responses of 221.32%, 242.65%, 317.09%, 373.96%, and 401.24% to 100 ppm of 2-butanone, acetone, 2-propanol, ethanol, and methanol, respectively. Experimental observation confirmed that the capacitive response inversely varied with the resonant frequency. Such an inverse relation was correlated with the dielectric variation at the junction interface, change in the molecular weights of VOCs, and their sticking coefficient. An equivalent circuit diagram with the help of adsorption–desorption isotherms and an energy band model is illustrated to correlate the device optimum capacitive response at the tuned frequencies under different VOC media. [ABSTRACT FROM AUTHOR]

A comparative analysis of three advanced architectures for tandem solar cells (SCs) is discussed, respectively: metal oxide, thin film, and perovskite. Plasmonic solar cells could further increase solar cell efficiency. Using this development, an innovative PV technology (an SHTSC based on metal oxides) represented by a four-terminal Cu2O/c-Si tandem heterojunction solar cell is investigated. The experimental and numerical modelling study defines the main aim of this paper. The experimental approach to SHTSCs is analysed: (1) a Cu2O layer is deposited using a magnetron sputtering system; (2) the morphological and optical characterization of Cu2O thin films is studied. The electrical modelling of silicon heterojunction tandem solar cells (SHTSCs) is discussed based on five simulation tools for the optimized performance evaluation of solar devices. The main novelty of this paper is represented by the following results: (1) the analysis suggests that the incorporation of a buffer layer can improve the performance of a tandem heterojunction solar cell; (2) the effect of interface defects on the electrical characteristics of the AZO/Cu2O heterojunction is discussed; (3) the stability of SHTSCs based on metal oxides is studied to highlight the degradation rate in order to define a reliable solar device. Perspectives on SHTSCs based on metal oxides, as well as Si perovskite tandem solar cells with metal oxides as carrier-selective contacts, are commented on. [ABSTRACT FROM AUTHOR]

In this paper, we report on a photocatalytic water-splitting device comprising a TiO2 photoanode combined with Se/TiO2heterojunction photovoltaic (PV) devices. A Se/TiO2PV device can supply its photo-induced open circuit voltage to a TiO2-Pt photoelectrochemical cell (PEC) in order to assist photoelectrolysis for H2 and O2 gas generation without external electrical sources. The open circuit voltage was increased from 0.65 V to approximately 3.2 V by the serial connection of five Se/TiO2PV devices. Hydrogen and oxygen bubbles were successfully generated by only light illumination without using any wired external voltage source. A photoanode with sol–gel derived porous TiO2films was used to increase the surface area to attain a stronger photocatalytic reaction. Microdot patterns of Pt were formed as the co-catalyst on a TiO2photoanode to suppress the back reaction of the photogenerated carrier. A Pt anode was formed on a glass substrate. Parameters related to the photocatalytic reaction, such as atmospheric pressure, the type of chemical additive, and the area ratio of Pt co-catalyst patterns to the surface area of the TiO2photoanode, were varied to generate a larger gas volume with the water-splitting device. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (QDs) and organic materials have great research potential in the field of optoelectronic devices. In this paper, MEH-PPV/CsPbBr3 heterojunction photodetectors (PDs) are prepared by spin coating method based on the good photoelectric properties of CsPbBr3 perovskite QDs and MEH-PPV. The MEH-PPV/CsPbBr3 heterojunction improves the energy level arrangement, and CsPbBr3 QDs can passivate the surface defects of MEH-PPV films to achieve effective charge separation and transfer, thus inhibiting the dark current and improving the photoelectric performance of the device. Under 532 nm laser irradiation, the responsivity (R) of MEH-PPV/CsPbBr3 heterojunction PD is 11.98 A W−1, the specific detectivity (D *) is 6.98 × 1011 Jones, and the response time is 15/16 ms. This work provides experience for the study of perovskite QDs and organic materials heterojunction optoelectronic devices. [ABSTRACT FROM AUTHOR]

Ferroelectric photovoltaic (PV) materials have garnered considerable interest because of their distinctive switchable PV characteristics. Nevertheless, their ability to function within a wide range of ambient temperatures was previously constrained. This paper describes the construction of ferroelectric capacitors featuring an Au/PZT (Pb(Zr 0. 40 Ti 0.60)O 3)/FTO (SnO 2 :F) heterojunction through the utilization of the sol-gel technique. The performance analysis findings indicate that the PZT material, following optimization of annealing temperature, displayed strong ferroelectric properties and notable frequency-dependent dielectric behavior. An increase in temperature (25°C∼300°C) revealed that short-circuit current density J sc exhibited an upward → downward → upward trend and reached 399.6 μA/cm2 at 300°C. Energy band analysis showed the presence of spontaneous polarization and a large work function difference between the bottom electrode FTO and the top electrode Au (∼0.42 eV) created a strong built-in electric field in the PZT films, which was conducive to the photogenerated carriers' separation and greatly improved the PZT film ferroelectric PV. In this paper, transparent ferroelectric materials were demonstrated for the first time to exhibit a photoelectric responsivity of up to 1.77 mA/W at a temperature of 300°C, offering a practical strategy for the implementation of transparent ferroelectric photovoltaic devices in high-temperature environments, particularly those subjected to intense solar energy harvesting and conversion. [ABSTRACT FROM AUTHOR]

The cooling requirement for long-wave infrared detectors still creates significant limitations to their functionality. The phenomenon of minority-carrier exclusion and extraction in narrow-gap semiconductors has been intensively studied for over three decades and used to increase the operating temperatures of devices. Decreasing free carrier concentrations below equilibrium values by a stationary non-equilibrium depletion of the device absorber leads to a suppression of Auger generation. In this paper, we focus on analyzing exclusion and extraction effects separately, based on experimental and theoretical results for a HgCdTe photodiode. To carry out an experiment, the n+-P+-π-N+ heterostructure was grown by metal organic chemical vapor deposition on CdTe-buffered GaAs substrate. In order to separate the extraction and exclusive junctions, three different devices were evaluated: (1) a detector etched through the entire n+-P+-π-N+ heterostructure, (2) a detector made of the P+-π photoconductive junction and (3) a detector made of the π-N+ photodiode junction. For each device, the dark current density–voltage characteristics were measured at a high-temperature range, from 195 K to 300 K. Next, the carrier concentration distribution across the entire heterostructure and individual junctions was calculated using the APSYS simulation program. It was shown that when the n+-P+-π-N+ photodiode is reverse biased, the electron concentration in the π absorber drops below its thermal equilibrium value, due to the exclusion effect at the P+-π junction and the extraction effect at the π-N+ junction. To maintain the charge neutrality, the hole concentration is also reduced below the equilibrium value and reaches the absorber doping level (NA), leading to the Auger generation rate's reduction by a factor of 2ni/NA, where ni is the intrinsic carrier concentration. Our experiment conducted for three separate detectors showed that the exclusion P+-π photoconductive junction has the most significant effect on the Auger suppression—the majority of the hole concentration drops to the doping level not only at the P+-π interface but also deep inside the π absorber. [ABSTRACT FROM AUTHOR]

Hydrogen, as a clean, safe, and efficient energy carrier, is one of the hot energy sources that have attracted much attention. Mo2C, due to the introduction of C atoms, makes the atomic spacing of the Mo lattice decrease and changes the width of the d-band, which makes the electronic properties of Mo2C similar to that of Pt noble metals, exhibiting excellent electrochemical hydrogen precipitation performance. MoS2, due to its special crystal structure and tunable electronic structure, has been widely studied. In this paper, Mo2C nanoparticles were prepared by high-temperature carbonization, and then two-dimensional layered MoS2 were be loaded on Mo2C nanoparticles by the hydrothermal method to synthesize Mo2C/MoS2 composite catalysts. Their electrochemical hydrogen precipitation (HER) performance under acidic conditions was tested. The above catalysts were also characterized by modern material testing methods such as XRD, SEM, TEM, and XPS. The results showed that the composite catalysts exhibited the most excellent electrochemical hydrogen precipitation performance at Mo2C/MoS2-3, with the lowest overpotential at a current density of 10 mA cm−2, Tafel slope, and electrochemical impedance. At the same time, the electrochemically active area was dramatically enhanced, with good stability under prolonged testing. The catalytic activity was significantly improved compared with that of Mo2C and MoS2. The characterization and experimental results indicate that the heterogeneous structure of Mo2C and MoS2 formed a built-in electric field between the two, which accelerated the electron transfer efficiency and provided more active sites. The Mo2C/MoS2 composite catalyst is a low-cost, easy-to-prepare, and high-efficiency electrochemical hydrogen precipitation catalyst, providing a new idea for developing green and clean energy. [ABSTRACT FROM AUTHOR]

To solve the shuttling effect and transformations of LiPSs in lithium–sulfur batteries, heterostructures have been designed to immobilize LiPSs and boost their reversible conversions. In this paper, we have constructed AlN/InN heterojunctions with AlN with a wide band gap and InN with a narrow band gap. The heterojunctions show metallic properties, which are primarily composed of 2s, 2p N atoms and 5s, 5p In atoms. InN has relatively higher adsorptivity for LiPSs than AlN. Reaction profiles show that on the surface of AlN, there is a lower rate-limiting step than on that of InN, from S8 to Li2S6, and a higher rate-limiting step from Li2S4 to Li2S2, which is more favorable for InN during the reduction from Li2S4 to Li2S2. The heterojunction can realize the synergistic reaction of trapping–diffusion–conversion for LiPSs, in which AlN traps large Li2S8 and Li2S6, the heterojunction causes the diffusion of Li2S4, and InN completes the conversion of Li2S4 to Li2S. [ABSTRACT FROM AUTHOR]

In this paper, a SiGe/Si heterojunction inductive line tunneling tunnel field-effect transistor with source Schottky contact (SC HJLT-iTFET) is proposed and investigated by the Sentaurus Technology Computer Aided Design (TCAD) simulator. By utilizing an appropriate source Schottky metal, the need for multiple ion implantation and annealing steps required for traditional P–I–N TFETs can be avoided, and the problems of self-alignment and random dopant fluctuations (RDF) during ion implantation can be solved. A high ON-state current (I ON) is obtained as fully overlapping the source and gate by line tunneling mechanism dominated, the appropriate Si1− x Ge x mole fraction material in the source region and high-k gate dielectric employed can further improve I ON. The incorporation of the block layer effectively decreases the lateral electric field at the drain end to reduce the OFF-state current (I OFF). Furthermore, the proposed charge enhancement layer (CEL) on the SiGe channel can suppress the Fermi level pinning effect (FLP) and enhance the charge of the source region. Based on the feasibility of the practical fabrication process, and the rigorous simulations indicate that the device has an SSavg of 19.8 mV/dec and SSmin of 6.8 mV/dec at V D = 0.2 V, I ON of 2.27 × 10−6 A μ m−1, and an I ON/ I OFF ratio of 1.02 × 1010, with extremely fast switching speed. These features make the device suitable for future ultra-low power applications on the internet of things, artificial intelligence, and related fields. [ABSTRACT FROM AUTHOR]

In this paper, a novel asymmetric trench SiC MOSFET with a Poly-Si/SiC heterojunction diode (HJD-ATMOS) is designed to improve its reverse conduction characteristics and switching performance. This structure features an integrated heterojunction diode, which improves body diode characteristics without affecting device static characteristics. The heterojunction diode acts as a freewheeling diode during reverse conduction, reducing the cut-in voltage (Vcut-in) to a lower level than conventional asymmetric trench SiC MOSFET (C-ATMOS), while maintaining a similar breakdown voltage. Meanwhile, the split gate structure reduces gate-to-drain charge (Qgd). Through TCAD simulation, the HJD-ATMOS decreases Vcut-in by 53.04% compared to the C-ATMOS. Both Qgd and switching loss are reduced, with a decrease of 31.91% in Qgd and 40.29% in switching loss. [ABSTRACT FROM AUTHOR]

During the past decade, Gallium Oxide (Ga2O3) has attracted intensive research interest as an ultra-wide-bandgap (UWBG) semiconductor due to its unique characteristics, such as a large bandgap of 4.5–4.9 eV, a high critical electric field of ~8 MV/cm, and a high Baliga's figure of merit (BFOM). Unipolar β-Ga2O3 devices such as Schottky barrier diodes (SBDs) and field-effect transistors (FETs) have been demonstrated. Recently, there has been growing attention toward developing β-Ga2O3-based heterostructures and heterojunctions, which is mainly driven by the lack of p-type doping and the exploration of multidimensional device architectures to enhance power electronics' performance. This paper will review the most recent advances in β-Ga2O3 heterostructures and heterojunctions for power electronics, including NiOx/β-Ga2O3, β-(AlxGa1−x)2O3/β-Ga2O3, and β-Ga2O3 heterojunctions/heterostructures with other wide- and ultra-wide-bandgap materials and the integration of two-dimensional (2D) materials with β-Ga2O3. Discussions of the deposition, fabrication, and operating principles of these heterostructures and heterojunctions and the associated device performance will be provided. This comprehensive review will serve as a critical reference for researchers engaged in materials science, wide- and ultra-wide-bandgap semiconductors, and power electronics and benefits the future study and development of β-Ga2O3-based heterostructures and heterojunctions and associated power electronics. [ABSTRACT FROM AUTHOR]

In this study, a heterojunction (P+ a-SiC/i intrinsic/n-Si) solar cell has been examined and characterized using the Analysis of Microelectronics and Photonic Structures (AMPS-1D) simulator. In this heterojunction solar cell, an intrinsic layer is imposed to enhance the efficiency and performance. The optimum efficiency of 36.52% (Voc = 1.714 V, Jsc = 27.006 mA/cm2, and FF = 0.789) has been achieved with this intrinsic layer. It has also been observed the solar cell without intrinsic layer. In this case, the maximum efficiency of 2.378% has been observed which is very poor. The heterojunction solar cell also has been investigated with electron blocking layer (EBL) and defect layer. In this case, the simulation result shows the lower efficiency (34.357%) than the previous. This research paper introduces an optimized model of a heterojunction solar cell enhanced with an intrinsic layer to improve efficiency. The proposed design shows significant promise in its theoretical framework. Looking forward, the design could be realized in laboratory settings and has the potential to be scaled up for broader applications. [ABSTRACT FROM AUTHOR]

To enable the application to next-generation devices of semiconductor nanowires (NWs), it is important to control their formation and tune their functionality by doping and the use of heterojunctions. In this paper, we introduce formation and the characterization methods of nanowires, focusing on our research results. We describe a top-down method of controlling the size and alignment of nanowires that shows advantages over bottom-up growth methods. The latter technique causes damage to the nanowire surfaces, requiring defect removal after the NW formation process. We show various methods of evaluating the bonding state and electrical activity of impurities in NWs. If an impurity is doped in a NW, mobility decreases due to the scattering that it causes. As a strategy for solving this problem, we describe research into core–shell nanowires, in which Si and Ge heterojunctions are formed in the diameter direction inside the NW. This structure can separate the impurity-doped region from the carrier transport region, promising as a channel for the new ultimate high-mobility transistor. [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]

This document discusses the application of photocatalysts in environmental chemistry, specifically in the removal of contaminants from wastewater and the production of renewable energy. The use of titanium dioxide (TiO2) as a photocatalyst is highlighted, along with its limitations such as high recombination rate and the need for UV radiation. The document presents various approaches to overcome these limitations, including doping TiO2 with different materials, coupling it with other semiconductors, and creating heterojunctions. The document also includes studies on the use of other photocatalysts such as ZnO, copper sulfides, and ilmenite. Additionally, it explores the use of photocatalysis for water disinfection and the inactivation of microorganisms. Overall, this Special Issue provides a comprehensive overview of the field of photocatalysis and the advanced techniques used to enhance catalyst efficiency. [Extracted from the article]

The review paper provides a comprehensive analysis of nickel oxide (NiO) as an emerging material in environmental monitoring by surveying recent developments primarily within the last three years and reports the growth processing and strategies employed to enhance NiO sensing performance. It covers synthesis methods for pristine NiO, including vapor-phase, liquid-phase, and solution-processing techniques, highlighting advantages and limitations. The growth mechanisms of NiO nanostructures are explored, with a focus on the most recent research studies. Additionally, different strategies to improve the gas sensing performance of NiO are discussed (i.e., surface functionalization by metallic nanoparticles, heterostructure formation, carbon-based nanomaterials, and conducting polymers). The influence of these strategies on selectivity, sensitivity, response time, and stability of NiO-based sensors is thoroughly examined. Finally, the challenges and future directions that may lead to the successful development of highly efficient NiO-based gas sensors for environmental monitoring are introduced in this review. [ABSTRACT FROM AUTHOR]

In this paper, the effects of the thermostability, band structure, and the external electric field on the electronic structure of MoSe2/Arsenene heterojunction are calculated based on the density functional theory. The calculation results show that the MoSe2/Arsenene heterojunction is a type-II heterojunction with a bandgap of 0.89 eV. When MoSe2 and arsenene combine by van der Waals force, the electrons are transferred from MoSe2 to arsenene, the holes are transferred from arsenene to MoSe2, with the direction of the internal electric field from MoSe2 to arsenene. The MoSe2/Arsenene heterojunction with valence band top and conduction band bottom contributed by arsenene and MoSe2, respectively, shows excellent thermostability at room temperature. The external electric field can effectively modulate the electronic structure of heterojunction. When the electric field is negative, electrons are transferred from MoSe2 to arsenene and holes from arsenene to MoSe2. The Fermi level of arsenene moves down while that of MoSe2 moves up. When the electric field is positive, the direction of electron and hole transfer are opposite to that when the electric field is negative. The Fermi energy level of arsenene and MoSe2 also move in the opposite direction. [ABSTRACT FROM AUTHOR]

In this paper, based on the first-principle calculations of hybrid density functional theory, the MoSTe/g-GeC of the Z-scheme heterostructure is constructed. The stability, electronic properties, optical absorption properties, and photocatalytic mechanism of the heterostructure is investigated. The band structure of MoSTe/g-GeC heterostructure is staggered, and the bandgap is 0.47 eV. The built-in electric field from g-GeC to MoSTe, with a size of 1.03 eV. The optical absorption coefficient of MoSTe/g-GeC heterostructures is significantly higher than that of MoSTe and g-GeC layer. When pH ranges from 0 to 7, the reduction reaction occurs in g-GeC layer, and the oxidation reaction occurs in the MoSTe layer. In the MoSTe/g-GeC heterostructure under different stresses, the band structure is arranged in a staggered manner. Importantly, under tensile strain, the bandgap of MoSTe/g-GeC heterostructure can be changed from the indirect into a direct bandgap. The bandgap of heterostructure decreases under the strain. In addition, the analysis of the photocatalytic mechanism shows that the redox reaction of the MoSTe/g-GeC heterostructure occurs on the layer with strong redox ability, and their light absorption ability is significantly enhanced compared to single-layers, which effectively improves the photocatalytic properties. It's a potential high-efficiency photocatalytic materials for direct Z-scheme heterostructure. In this paper, the stability, electronic properties, optical absorption properties, and photocatalytic mechanism of the MoSTe/g-GeC heterostructure is systematically studied. The results show that the heterostructure is a direct z-scheme heterostructure, and the photocatalytic performance is better than that of MoSTe and GeC monolayers. [Display omitted] • MoSTe/g-GeC heterostructure is a direct Z-scheme heterostructure, which is suitable for photocatalytic water splitting. • MoSTe/g-GeC heterostructure has excellent absorption coefficient (9.8 × 104 cm−1) in the visible and ultraviolet ranges. • The bandgap of MoSTe/g-GeC heterostructure can change from indirect bandgap to direct bandgap under partial strain. [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]

Carbon nitride MXene exhibits good metal conductivity, high photothermal conversion, carrier mobility, and high exposure of active sites, which makes it a promising co-catalyst for photothermal synergistic transformation of CO2. In this paper, Ti3CN/TiO2 heterojunction was constructed in situ using Ti3CN as TiO2 precursor to investigate the performance of Ti3CN MXene in photothermal synergistic transformation of CO2, and then the monolayer structure was utilized to enhance the interfacial charge transfer and improve the photothermal catalytic activity of Ti3CN. The catalysts were characterized by SEM, XRD, XPS, and UV-Vis DRS, and it was found the heterojunction constructed by monolayer MXene had a narrower bandgap and a higher carrier generation mobility, which, combined with the catalytic activity test, proved the single monolayer Ti3CN MXene had better photothermal synergistic conversion efficiency of CO2, and the heterojunction yield was 11.36 μmol·g−1·h−1 after layering, compared with that before layering (9.41%), which was 1.2 times higher than that before layering (9.41 μmol·g−1·h−1). [ABSTRACT FROM AUTHOR]

A novel photocatalyst is designed by surface modification and cocatalyst loading of graphitic carbon nitride (g-C 3 N 4) with ammonium hydroxide and silver nanocubes (AgNCs), respectively. The synergistic effect of the modification in the intralayer of g-C 3 N 4 and surface plasmon resonance (SPR) bands of AgNCs significantly enhances the migration and separation efficiency of photo-induced charge carriers. A nickel mesh coated with photocatalyst and the carbon paper loaded with pristine g–C 3 N 4 –mixed iron phthalocyanine (FeIIPc) used as the photoanode and cathode, respectively, are constructed for the self-powered photoelectrochemical cell, which exhibits the maximum power density of 0.74 mW cm−2. The AHCN/AgNCs-based cell reveals approximately a 3.1-times enhancement in maximum power density compared with the pristine g–C 3 N 4 –based cell. In addition, the photocatalytically generated H 2 O 2 (chemical energy) can be stored in water, and then used as fuel by the connection of two electrodes in the dark. After the fuel cell is operated for 12 h, the specific capacitance retention rate still maintains as high as 57.2 %, which is the greatest retention rate in comparison with the previously reported H 2 O 2 fuel cell systems. Our work offers a feasible opinion on how to improve the visible light utilization of semiconductors by tuning the intralayer properties and loading plasmonic metal. • A novel composite photocatalyst (AHCN/AgNCs) is applied in the H 2 O 2 fuel cell. • The metal-semiconductor heterojunction facilitate the photocatalytic H 2 O 2 production. • The AHCN/AgNCs produces 0.045 M H 2 O 2 under light irradiation for 2.5 h. • The specific capacitance keeps 57.2 % of initial value after 12 h of cell operation. [ABSTRACT FROM AUTHOR]

The development of two-dimensional materials is currently rapid due to their outstanding electronic and optical properties, and research on them has never ceased. Our study explored the geometric and electro-optical characteristics of a novel BAs/ZnSe heterostructure through first-principles calculations. We also researched the effects of P atom doping and the stacking of rotated monolayers on the functioning of the BAs/ZnSe heterostructure. Findings from our analysis suggest that the BAs/ZnSe heterostructure embodies a type-II heterojunction, and its band gap is 0.38 eV. This configuration facilitates the efficient division of photoexcited electron–hole pairs at the heterointerface. When the layer spacing reaches 3.3 Å, the binding energy is the lowest and the heterojunction is the most stable. The introduction of an electric field and mechanical stress will lead to the modification of the heterostructure's band gap, ultimately reducing it to zero, thereby exhibiting metallic properties. It is noteworthy that when using an electric field range of −0.9 < Eext < −0.7 eV Å−1, the BAs/ZnSe heterostructure transfers from a type-II heterojunction to a type-I heterojunction, and becomes a direct band gap. A similar transition also occurs when the applied stress range is 3% < ε < 6%, and there's a type-I to type-II transition. In particular, compared to the individual monolayers, the BAs/ZnSe heterostructure exhibits enhanced optical absorption coefficients, notably in the ultraviolet absorption spectrum, exhibiting an expanded range of absorption. The light absorption capability will also vary with different electric fields and strains. This suggests that the BAs/ZnSe heterostructure can shine in a wider range of applications. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides are considered to be the most promising battery-type cathodes to construct hybrid supercapacitors. The rational design and construction of multi-anion-based heterojunctions with multi-interface structures, such as sulfoselenide and oxyselenide, are significant and necessary. In this work, a bimetallic sulfoselenide–selenite heterojunction, (Ni,Co)(Se,S)2/(Ni,Co)SeO3, was facilely synthesized by a simple one-pot hydrothermal method using NiCo–LDH as a template. The rough surface of the nanosheet array provides more active sites and the multi-interface optimizes the electronic structure for electrochemical reactions. As a battery-type cathode for supercapacitors, the optimized (Ni,Co)(Se,S)2/(Ni,Co)SeO3-1 exhibits a high specific capacitance of 7.61 F cm−2 at a current of 2 mA cm−2. In addition, the assembled HSC device provides a high energy density of 0.59 mW h cm−2 at a power density of 1.44 mW cm−2 and displays a capacitance retention rate of 84.38% after 5000 charge/discharge tests. These results demonstrate a green, safe and simple method to prepare bimetallic sulfoselenide–selenite heterojunctions from LDH-based templates as high-capacity battery-type materials for hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

Achieving highly selective, highly responsive detection of formaldehyde gas at ppb level at room temperature is highly challenging for air monitoring and life health observation. Therefore, in this paper, low-cost, easy-to-fabricate, highly responsive as well as highly selective Zn 2 SnO 4 /SnO 2 (ZTO/SnO 2) metal-oxide semiconductor gas sensors have been successfully prepared by using one-pot hydrothermal method. The results showed that the synergistic effect of the n-n heterojunction formed between ZTO/SnO 2 prepared by this method led to a substantial increase in the sensitivity to the target gases, and ZTO/SnO 2 -3 a higher response (291) to 100 ppm formaldehyde compared to the response values of pure samples of Zn 2 SnO 4 (20.4) and pure SnO 2 (6.99) at room temperature. In addition, the response value for formaldehyde reached about 16.5–295 times higher than that for other common hazardous gases (100 ppm) in our lives. The ZTO/SnO 2 -3 sample with 1 mol/L NaOH was homogeneous and small, exposing as much surface as possible, and the theoretical minimum detection limit was calculated to be 50 ppb. Therefore, the large specific surface area and active adsorption/interaction sites are favorable for gas sensing. This work provides an excellent way to prepare gas-sensitive characteristic sensors using NaOH to improve the surface structure. [ABSTRACT FROM AUTHOR]

The employment of catalysts to split water to create hydrogen is viewed as an effective solution to the energy crisis problem. In this work, type II heterojunction CdIn2S4/g-C3N4 nanocomposites with different mass ratios were successfully synthesised using a simple sonication technique. The results show that the constructed CdIn2S4/g-C3N4 heterojunctions exhibit better catalytic performance in the photoelectrocatalytic water splitting reaction, and the photocurrent density of the composite with a composite ratio of 15% reaches 0.35 mA cm−2 at 1.23 V (vs. RHE), which is a 2.33-fold enhancement relative to g-C3N4. The constructed heterojunction facilitates the photogenerated charge transfer between CdIn2S4 and g-C3N4, effectively accelerating the separation of photogenerated electrons and holes. This work provides theoretical guidance for efficient PEC water splitting technology. [ABSTRACT FROM AUTHOR]

Significant global concerns about the environment include the removal of various organic dye contaminants and the detection of toxic nitrite (NO2−). Herein, we developed a novel composite that combines an inorganic perovskite-based alkaline earth stannate (CaSnO3) with aurivillius oxide (Bi2WO6). These components were synthesized by combustion and hydrothermal methods, respectively. The composite was designed for the photocatalytic degradation of methylene blue (MB) and electrochemical sensing of nitrite. The prepared composite was systematically characterized using various analytical techniques to verify its elemental composition and morphology and to determine the particle size and band gap. CaSnO3/Bi2WO6 exhibited a remarkable 92.5% degradation of the carcinogenic MB dye under UV light over approximately 180 minutes. Importantly, it was observed that the designed nanocomposite did not exhibit photo-corrosion properties as the degradation of MB occurred even at pH 11. Furthermore, the CaSnO3/Bi2WO6-modified glassy carbon electrode (GCE) demonstrated excellent electrocatalytic activity, with an obtained limit of detection (LOD) of 0.9 μM. In this work, the CaSnO3/Bi2WO6 nanocomposite shows promising potential for efficient photocatalytic dye degradation and electrochemical sensing of nitrite, with the added advantage of avoiding photo-corrosion even under alkaline conditions. [ABSTRACT FROM AUTHOR]

In this paper, the structure and electronic properties of InP/PtS 2 heterojunction as well as the photocatalytic and solar hydrogen production efficiency are studied by first principles. Studies have shown that InP/PtS 2 heterojunction is type II band alignment, typical Z heterostructure, has strong light absorption coefficient in the absorption spectrumand, InP/PtS 2 heterojunction with an indirect bandgap of 1.97 eV，the band edge positions that meet the energy band prerequisites for water splitting across different pH levels，The band edge positions and light absorption capabilities have been modified through biaxial strain, with tensile strain enhancing the absorption capacity within the visible light spectrum ranging from 450 to 800 nm(nm). The InP/PtS 2 heterojunction achieves a solar-to-hydrogen conversion efficiency (ηSTH) of 32.5%, which is higher than that of most heterojunctions. The InP/PtS 2 heterojunction is anticipated to emerge as a promising contender for the next generation of photocatalysts. InP/PtS 2 heterojunction is a typical direct Z-scheme heterojunction, which can change its electronic and optical properties under strain, and may contribute to the fields of water splitting. The solar-to-hydrogen efficiency of the InP/PtS2 heterostructure can reached 32.5%. The absorption coefficient in the visible range is enhanced by the application of strain. [Display omitted] • Compared with InP monolayer and PtS 2 monolayer, InP/PtS 2 heterojunctions have better visible light absorption efficiency. • The InP/PtS 2 heterojunction achieves a solar-to-hydrogen conversion efficiency (ηSTH) of 32.5%, which is higher than that of most heterojunctions. [ABSTRACT FROM AUTHOR]

Layered lanthanum titanate (La2Ti2O7) perovskite is a good photocatalytic material owing to its high stability, strong redox ability, and non-toxicity. However, its inherent wide bandgap limits its application in photocatalytic hydrogen evolution. Therefore, combining La2Ti2O7 with two-dimensional (2D) narrow-bandgap semiconductors to form 2D/2D layered structures is the preferred strategy to improve its photocatalytic performance. In this study, a novel 2D/2D ZnIn2S4/La2Ti2O7 Z-scheme heterojunction was prepared through a solvothermal method. The experimental results show that when the molar ratio of La2Ti2O7 to ZnIn2S4 is 1 : 4, the hydrogen evolution rate of the composite under ultraviolet-visible light reaches 6.97 mmol g−1 h−1, which is 3.5 times higher than that of the pure ZnIn2S4. The results of the morphological characterization studies of the samples and the photoelectrochemical measurements show that channels for the rapid transfer of carriers are generated by the unique 2D/2D structure of these samples, and the separation and migration efficiency of the photogenerated carriers significantly improved due to the formation of the Z-scheme heterojunction. This study provides useful insights into the modulation of wide-bandgap semiconductors and research into solar energy conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • In 2 O 3 quantum dots were successfully loaded on g-C 3 N 4 by pre-forming In–N bonds. • High-temperature oxidation can improve the oxygen adsorption capacity of g-C 3 N 4. • S-scheme transfer exhibits excellent photoelectric conversion efficiency. • Hydroperoxide C β intermediate was an important intermediate in lignin β–O–4 bond cleavage reaction. The graphitic carbon nitride (g-C 3 N 4) photocatalysis has emerged as a clean method for cleaving lignin-linked bonds due to its mild and sunlight-driven reaction conditions. The fast electron–hole pair complex of g-C 3 N 4 constrains its degradation efficiency, making the heterojunction construction a popular solution. The conventional methods of preparing g-C 3 N 4 heterojunctions by physical mixing destroy π-conjugations in g-C 3 N 4 , reducing the adsorption of lignin containing benzene rings. In this study, a novel indium oxide (In 2 O 3) quantum dot–g-C 3 N 4 0D/2D heterojunction was prepared through the high-temperature oxidation of pre-prepared indium-doped g-C 3 N 4. The introduction of In 2 O 3 at the quantum dot level minimizes the interference with lignin adsorption capacity. The strong combination of the two (In 2 O 3 and g-C 3 N 4) increases the intersection interface area, promoting the S-scheme transfer route of the photogenerated electrons. Consequently, this enhances the photoelectric conversion efficiency and carrier lifetime of the heterojunction, and inhibits the rapid recombination of photogenerated electron–hole pairs in g-C 3 N 4. The proposed heterojunction was 3 times more efficient than g-C 3 N 4 alone for selective cleavage of lignin β–O–4 bonds after 2 h of sunlight irradiation. Combined with inhibitor experiments and gas chromatography–mass spectrometry analysis, this paper defines the reactive oxides and proposes a cleavage pathway for the lignin β–O–4 bonds in In 2 O 3 –g-C 3 N 4 heterojunction system. [ABSTRACT FROM AUTHOR]

This paper presents a hydrogen sensor made of WSe 2 modified monocrystalline SnSe 2 nanolayer. The hydrogen sensitive property of tungsten diselenide (WSe 2) and tin diselenide (SnSe 2) was found by hydrothermal adjustment of the molar ratio. The samples were characterized for their crystal structure, microstructure, morphology, and elemental composition, and the morphology and heterojunction formation of the nanocomposites were confirmed. When the optimal molar ratio is 1:1 and the optimal working temperature is 270 °C, the WSe 2 /SnSe 2 sensor have good sensing properties for hydrogen, and the sensitivity for 100 ppm hydrogen is about 7.27. Finally, the experiment proves that WSe 2 /SnSe 2 gas sensor has a unique selection of hydrogen and has a wide application prospect in hydrogen detection in the future. The gas sensing mechanism of the hydrogen sensor is discussed based on its material structure. • A hydrogen sensor with WSe 2 modified monocrystalline SnSe 2 was proposed. • The sensor has the best response to hydrogen at 270 °C. • The enhanced sensing mechanism with p-n heterojunction is discussed. • Hydrogen sensor has fast response and long-term stability. [ABSTRACT FROM AUTHOR]

Constructing an S-scheme system with highly active catalysts is a significant approach for improving the separation of photoinduced carriers to solve the related environmental aggravation. In this study, a well-designed S-scheme AgVO3/CaIn2S4 photocatalyst was synthesized for water purification by in situ growing CaIn2S4 nanocrystals on AgVO3 nanorod surfaces. The optimized AgVO3/CaIn2S4 heterostructure demonstrates an enhanced photocatalytic efficiency (94.1%) toward tetracycline hydrochloride (TCH) degradation compared with bare AgVO3 (42.6%) and CaIn2S4 (81.6%). The significant enhancement of photocatalytic activity is attributed to the S-scheme charge transfer mechanism in the AgVO3/CaIn2S4 heterostructure, which effectively directs photogenerated charge migration, boosts charge transfer, and preserves the high redox capacity of photoexcited electrons and holes on different active sites. This study is expected to offer insights into strategically designing and preparing S-scheme heterojunction photocatalysts to improve water purification. [ABSTRACT FROM AUTHOR]

Photocatalytic ammonia production holds immense promise as an environmentally sustainable approach to nitrogen fixation. In this study, In2O3/In2S3-ZnCdS ternary heterostructures were successfully constructed through an innovative in situ anion exchange process, coupled with a low-temperature hydrothermal method for ZnCdS (ZCS) incorporation. The resulting In2O3/In2S3-ZCS photocatalyst was proved to be highly efficient in converting N2 to NH3 under mild conditions, eliminating the need for sacrificial agents or precious metal catalysts. Notably, the NH4+ yield of In2O3/In2S3-0.5ZCS reached a significant level of 71.2 μmol g−1 h−1, which was 10.47 times higher than that of In2O3 (6.8 μmol g−1 h−1) and 3.22 times higher than that of In2O3/In2S3 (22.1 μmol g−1 h−1). This outstanding performance can be attributed to the ternary heterojunction configuration, which significantly extends the lifetime of photogenerated carriers and enhances the spatial separation of electrons and holes. The synergistic interplay between CdZnS, In2S3, and In2O3 in the heterojunction facilitates electron transport, thereby boosting the rate of the photocatalytic nitrogen fixation reaction. Our study not only validates the efficacy of ternary heterojunctions in photocatalytic nitrogen fixation but also offers valuable insights for the design and construction of such catalysts for future applications. [ABSTRACT FROM AUTHOR]

The residue of antibiotics and various pollutants has led to an urgent issue in environmental pollution control. In this study, we constructed an S-scheme P-TiO2@Zn-MOF heterojunction by self-assembling phosphonate-based MOFs on mesoporous phosphate-TiO2 beads. Compared to monomers, the P-TiO2@Zn-MOF2.0 heterojunction exhibits significantly higher photocatalytic activity for the photo-oxidative degradation of ciprofloxacin (97.2% in 60 min) and tetracyclic (TC) (94.5% in 100 min) and the photo-reduction of Cr(VI) (92.7% in 60 min) under simulated sunlight. Experimental results and calculations revealed the effective separation and transfer of photogenerated carriers at the P-TiO2@Zn-MOF2.0 S-scheme heterojunction interface, enabling the formation of highly active superoxide and hydroxyl radicals. Furthermore, the hybrid maintained excellent Cr(VI) photoreduction performance after recycling tests in actual electroplating industry wastewater at a strongly acidic pH. [ABSTRACT FROM AUTHOR]

Element doping and construction of heterojunction composites are the most common ways to enhance g-C3N4, which are very attractive in achieving high photocatalytic activity. In this study, 2D nanosheet structured BCN was obtained by doping B atoms with graphite carbon nitride. Subsequently, Ti MOFs were loaded on BCN to obtain a Z-scheme heterojunction composite TBCN through calcination. Under simulated sunlight, the photocatalytic hydrogen production rate of the TBCN heterostructure was 1242 μmol h−1 g−1, which was 2.2 times higher than that of BCN and 9.34 times higher than that of bulk graphite carbon nitride (GCN). Experimental results showed that the construction of a Z-scheme heterojunction composite (TBCN) could effectively adjust the material band gap position, expand the light absorption range, enhance electron transfer and inhibit electron–hole recombination, which are crucial for efficient photocatalysis. This study not only provides a strategy for constructing heterojunction composites in the field of g-C3N4 photocatalytic hydrogen evolution, but also deeply analyzes the electron migration direction and the reasons for enhancing carrier separation in the Z-type heterojunction scheme, thus providing potential guidance for future research. [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]

The construction of heterojunctions is an effective strategy to improve the photogenerated carrier mobility rate and enhance the photocatalytic performance. The main bottlenecks in developing semiconductor photocatalysts lie in the poor light absorption and the fast recombination of photogenerated electron–hole pairs. In order to enhance the photocatalytic conversion of CO2, in this work, a kind of 2D/2D CuS/Ti3C2 heterostructure nanocomposites were designed. The formation of the heterojunction structure resulted in a significant enhancement of the light absorption range in the visible region of pristine Ti3C2 and a slight increase in the semiconductor bandgap width (2.58 eV), which in turn increased the generation of photogenerated electron–hole pairs and facilitated the acceleration of the carrier mobility efficiency, leading to a substantial improvement of the photocatalytic activity. After controlling the molar ratio of CuS/Ti3C2 at the optimum value of 1 : 8, the photocatalytic CO2 reduction conversion rate was the highest in the absence of co-catalysts. The yields of CO and CH4 were 10.68 and 25.21 μmol g−1 h−1, respectively, and were 5.51 and 3.15 times higher than that of pristine Ti3C2. Moreover, it resolved the bottleneck of the single CuS reduction product being only CO. In addition, the CuS/Ti3C2 (1 : 8) photocatalyst exhibited 35.07% selectivity and a C2H4 yield of 10.05 μmol g−1 h−1. The presence of large amounts of C1 and C2 intermediates on the catalyst surface was observed by in situ FTIR. Notably, after a cycling stability test lasting 40 h, the best samples retained 88.8% of the initial efficiency with good stability. This study further elucidates the mechanism of action and synergistic effects of CuS and Ti3C2 semiconductors in enhancing photoactivity. [ABSTRACT FROM AUTHOR]

In this paper, a novel preparation method (alkyne-based anionic method), had been used to prepare graphdiyne (GDY) with lamellar structure. Nanorods CoMoO 4 and nanosphere red phosphorus (P) was in situ loaded on the graphdiyne sheets using a morphology-modified method. Double S-type heterojunction of GDY/CoMoO 4 –P was built to improve the photocatalytic activity and stability. The hydrogen production of GDY/CoMoO 4 –P reached 14155.8 μmol g−1 h−1. The result of DFT theoretical calculation, ultraviolet and in-situ X-ray photoelectron spectroscopy characterization showed the construction of double S-type heterojunction accelerates the separation of photogenerated electrons/holes pairs and the transport of photogenerated electrons, enhance the absorption and utilization of light source. Through morphology control and heterojunction construction, the photocatalytic activity and stability was largely improved. This fully validates the feasibility that organic frameworks-GDY can be artificially constructed for photocatalytic hydrogen production. [Display omitted] • GDY/CoMoO 4 –P was successfully prepared by in situ deposition. • Design a ternary composite catalyst from the two aspects of morphology and band structure. • The addition of the GDY improves the redox ability of the entire system. • The recombination of photo-generated carriers was effectively suppressed. [ABSTRACT FROM AUTHOR]

A new cobalt-based metal–organic framework with the chemical formula of [Co2(DClTPA)2(DABCO)]·(DMF)4 (MUT-16) containing 1,4-diazabicyclo[2.2.2]octane (DABCO) and 2,5-dichloroterephthalic acid (DClTPA) has been designed and prepared through a solvothermal method. MUT-16 (MUT = Materials from University of Tehran) crystallized in a tetragonal system with I41/acd space group, based on single-crystal X-ray analysis. The Ag@MUT-16 nanocomposite was prepared using Ag nanoparticles (NPs) loaded into/onto porous MUT-16via photoreduction route (PR). The MUT-16 and Ag@MUT-16 were characterized using various techniques, such as PXRD, FT-IR, FE-SEM, TEM, EDX, N2 adsorption–desorption isotherms, TGA, DRS, PL, EIS, and Mott–Schottky measurements. The Ag@MUT-16 nanocomposite showed photocatalytic activity of 87.75% in the degradation of Quinoline Yellow (QY) after 30 min under visible light irradiation. The distinctive characteristics of the Ag@MUT-16 nanocomposite, such as the Fenton-like effect of Co2+ ions, surface plasmon resonance (SPR) of Ag NPs, Schottky junction at interfaces between Ag NPs and MUT-16, and reduction of electron–hole recombination through electron trapping by Ag NPs as co-catalyst, all play significant roles in the photocatalytic degradation of Quinoline Yellow (QY). [ABSTRACT FROM AUTHOR]

In this work, CoV-LDH/ZnIn2S4 (CoV-LDH/ZIS) nanocomposites were synthesized through a self-assembly process in order to investigate the influence of CoV-LDH addition on the rate of hydrogen production. XRD and TEM measurements confirmed the effective preparation of CoV-LDH/ZIS nanocomposites. Among all the nanocomposite photocatalysts, 2.0%-CoV-LDH/ZIS showed the best photocatalytic performance with a hydrogen production rate of 1397.3 μmol g−1 h−1, approximately 2.2 times that of pure ZnIn2S4 (ZIS). The X-ray photoelectron spectroscopy (XPS) measurement indicated that there is a strong interfacial interaction between ZIS and CoV-LDH, indicating that more than simple mechanical mixing had occurred. The steady-state fluorescence spectroscopy (PL) and time-resolved photoluminescence (TRPL) spectroscopy results showed that the electron and hole recombination in CoV-LDH/ZIS is significantly reduced and that efficient interface charge transfer and separation are achieved. This work sheds light on the interfacial electron transfer between two semiconductor materials, which promotes the separation of photogenerated carriers and thus enhances photocatalytic hydrogen production activity. [ABSTRACT FROM AUTHOR]