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A physical insight into the capture and emission behavior of interface/oxide states in a GaN-based metal-oxide-semiconductor (MOS) structure is of great importance to understanding the threshold voltage (VTH) instability in GaN power transistors. A time-dependent VTH shift in Ni/Al2O3/AlGaN/GaN MOS-HFETs (heterojunction field-effect transistors) and a distribution of Al2O3/III-nitride interface states (Dit) were successfully characterized by constant-capacitance deep level transient spectroscopy. It is found that in situ remote plasma pretreatments in plasma-enhanced atomic-layer-deposition could suppress Dit (EC-ET > 0.4 eV) down to below 1.3 × 1012 cm−2 eV−1. Under high applied gate bias (e.g., VG > 8 V), tunnel filling of oxide states in the Al2O3 dielectric comes into play, contributing to remarkable VTH instability in the MOS-HFETs. The tunnel distance between the 2D Electron Gas (2DEG) channel and oxide states ET,ox in the Al2O3 dielectric decreases from 3.75 to 0.82 nm as VG increases from 2 to 8 V. A further increase of VG to 11 V makes the Fermi level approach ET,ox (EC − ET ∼ 1.62 eV), which may enable direct filling. High electric field induced tunnel filling of gate oxide states could be an assignable cause for VTH instability in normally-OFF III-nitride MOS-HFETs. [ABSTRACT FROM AUTHOR]

Photocatalysis can create a green way to produce clean energy resources, degrade pollutants and achieve carbon neutrality, making the construction of efficient photocatalysts significant in solving environmental issues. Conjugated polymers (CPs) with adjustable band structures have superior light‐absorption capacity and flexible morphology that facilitate contact with other components to form advanced heterojunctions. Interface engineering can strengthen the interfacial contact between the components and further enlarge the interfacial contact area, enhance light absorption, accelerate charge transfer and improve the reusability of the composites. In order to throw some new light on heterojunction interface regulation at a molecular level, herein we summarize CP‐based composites with improved photocatalytic performance according to the types of interactions (covalent bonding, hydrogen bonding, electrostatic interactions, π‐π stacking, and other polar interactions) between the components and introduce the corresponding interface building methods, identifying techniques. Then the roles of interfaces in different photocatalytic applications are discussed. Finally, we sum up the existing problems in interface engineering of CP‐based composites and look forward to the possible solutions. [ABSTRACT FROM AUTHOR]

• VN/Mo 2 C heterointerfaces nanoparticles are monodispersed on N-doped carbon nanosheets. • Mo 2 C and VN synergistically promote the diffusion and conversion of polysulfides. • The functional separator also has excellent protective effect on the lithium anode. • The modified separator exhibits superb electrochemical performance in Li-S batteries. Lithium-sulfur (Li-S) battery is deemed as one of the optimal next-generation energy storage devices due to its low cost and high energy density. However, the shuttle effect of lithium polysulfide (LiPS), sluggish reaction kinetics, and fatal Li-dendrite growth hinder its practical applications. In this work, a bifunctional nitrogen-doped carbon nanosheet conductive framework embedded with VN-Mo 2 C heterointerfaces (VN/Mo 2 C@CNS) is reported as a separator modifier for both sulfur cathode and lithium anode. The VN/Mo 2 C@CNS can offer a synergistic effect of strong surface affinity, good catalytic activity, and small diffusion barrier to accelerate the conversion of polysulfides, which was confirmed by in-situ Raman and theoretical calculation. Moreover, the composite has good lithiophilicity, thus inhibiting the formation of dendrites and achieving uniform lithium deposition. Benefiting from the above merits, the Li-S cells with VN/Mo 2 C@CNS separator obtain desirable rate performance (687 mAh g−1 at 4 C), long cycle life of 1000 cycles (0.042 % capacity attenuation per cycle at 1 C), high areal capacity of 4.2 mAh cm−2 (under a high sulfur loading of 5.6 mg cm−2), and stable performance in protecting the Li anode (at 5 mA cm−2 for 1000 h). This work highlights a novel strategy for facilely designing heterostructures, offering valuable insights to tackle sulfur cathode and lithium anode challenges simultaneously for longevous Li-S batteries. [ABSTRACT FROM AUTHOR]

In2S3 (β-In2S3), semiconducting chalcogenide with desirable physicochemical properties, has fascinated researchers in photoelectrochemistry. Because of its wide band gap, In2S3 can utilize solar energy below 600 nm. However, rapid photogenerated electron–hole recombination and low quantum efficiency have limited the practical application of In2S3 in this field. In a two-step in situ hydrothermal process we introduced a narrow band gap semiconductor (ReS2) below the In2S3 and constructed a direct Z-scheme heterostructure with nanoflower and honeycomb morphology. The formation of a direct Z-scheme heterostructure and coordination of the trap-like structure of the composite give a wider absorption range, higher migration and separation efficiency, and faster interfacial transfer speed than for pristine In2S3, and the photoelectrochemical performance is approximately three times better than that of pristine In2S3 at 1.23 V versus a reversible hydrogen electrode under sunlight. This method therefore provides a new prospect for optimizing the performance of In2S3 and applying the novel heterojunction. [ABSTRACT FROM AUTHOR]

Abstract: The highly efficient charge generation and transport is realized by simply stacking several 1,4,5,8,9,11‐hexa‐azatriphenylene hexacarbonitrile (HAT‐CN)/4,4′,4″‐tris(N‐3‐methylphenyl‐N‐phenylamino) triph‐enylamine (m‐MTDATA) organic heterojunctions in series. Mechanism analysis confirms that the highly effective charge transport property benefits from the efficient charge generation and recombination processes at the HAT‐CN/m‐MTDATA interfaces. It is found that the efficient multialternating organic heterojunctions can be used not only as hole and electron transporters to supply large charge injection, but also as excellent charge generation layer (CGL) to fabricate high‐performance tandem organic light‐emitting diodes (OLEDs). The resulting red phosphorescent OLEDs by simultaneously using the multialternating organic heterojunctions as hole and electron transporters realize the power efficiency (PE) of 36.7 lm W−1, current efficiency (CE) of 28.0 cd A−1, and external quantum efficiency (EQE) of 15.4%, whereas the PE, CE, and EQE, respectively, reach 37.1 lm W−1, 56.0 cd A−1, and 31.8% when simultaneously using the multialternating organic heterojunctions as hole and electron transporters and CGL to fabricate tandem red phosphorescent OLEDs, indicating the validity of the multialternating organic heterojunctions as the charge generator and transporters. The results provide us a totally new way of fabricating high‐performance OLEDs. [ABSTRACT FROM AUTHOR]

Conjugated polymers, covalent bonding, heterojunctions, interface engineering, noncovalent interactions Frontispiece: Interface Engineering of Conjugated Polymer-Based Composites for Photocatalysis Keywords: conjugated polymers; covalent bonding; heterojunctions; interface engineering; noncovalent interactions EN conjugated polymers covalent bonding heterojunctions interface engineering noncovalent interactions 1 1 1 12/29/22 20221227 NES 221227 B Interface engineering b can facilitate the self-assembly of conjugated polymer-based composites through a series of intermolecular interactions (covalent bonding, hydrogen bonding, dipole-dipole interactions, electrostatic interactions, and - stacking) between the components, further improving the photocatalysis process, which depends heavily on smooth charge transfer at the well-formed interface. [Extracted from the article]

In this work, we utilized hydrothermal treatment method to prepare a new type of nanomaterial MoS/reduced graphene oxide (RGO) heterojunction with the graphite oxide assisted since it can provide the oxygen containing functional groups for MoS precusor to attach. The morphologies and microstructures of as prepared products are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Raman spectra and X-ray photoelectron spectroscopy. It is found that the MoS nanosheets have about seven layers which revealed the possibility of using RGO as an ideal support material for forming fewer layered MoS nanosheets. In addition, the obtained MoS/RGO nano heterojunction exhibit preferable electrical conductivity and photocurrent response activity under the illumination of simulated sunlight compared to pure MoS. [ABSTRACT FROM AUTHOR]

It is well known that one of the major challenges facing white organic light‐emitting diodes (WOLEDs) has been to achieve high efficiency, low efficiency roll‐off, and high color rendering index (CRI) simultaneously. A simple charge‐ and exciton‐confining emitting layer structure formed by employing a blue emitting p/n heterojunction, and combined with red, yellow, and green phosphorescent ultrathin layers, is presented, thus realizing the stable utilization of 100% excitons. The resulting hybrid WOLEDs exhibit the maximum forward‐viewing external quantum efficiency and power efficiency of 23.4% and 50.4 lm W−1, and keep them at 20.3% and 31.2 lm W−1 at 1000 cd m−2, showing high efficiency and low efficiency roll‐off. Furthermore, the device also shows extremely stable electroluminescent spectra in the whole luminance range with a high CRI of 93 and the Commission Internationale de L'Eclairage coordinates of (0.49, 0.43) at 1000 cd m−2, which is perfect warm white for indoor lighting. The achievement of the excellent comprehensive performances is the best result reported to date among the conventional blue fluorescence‐based hybrid WOLEDs possessing such high CRI, which may be a new starting point for further research on high‐performance hybrid WOLEDs. [ABSTRACT FROM AUTHOR]

Antimony sulfide (Sb 2 S 3) is widely used in photocatalysts and photovoltaic cells because of its abundant reserves, low toxicity, environmental friendliness, narrow band gap, and high light absorption capacity. Sb 2 S 3 shows a quasi-one-dimensional structure composed of [Sb 4 S 6 ] n nanoribbons, a lot of reported studies are focused on preparing Sb 2 S 3 with [hk1] oriented dominant growth to improve the photogenerated carrier transport capacity of Sb 2 S 3. However, there is relatively few research on the preparation of [hk1] oriented rod-like Sb 2 S 3 by vapor transport deposition (VTD) method. In this work, the VTD method was used to prepare Sb 2 S 3 with [hk1] oriented growth on the FTO substrate, and then composite with the ternary solid solution Cd x Zn 1−x S. Finally, a novel Sb 2 S 3 /Cd 0.6 Zn 0.4 S S-scheme heterojunction with rod-like core-shell structure was successfully constructed, which could effectively improve the photoelectrochemical properties. Because the solid solution component x is adjustable, that is, Cd x Zn 1−x S has continuously adjustable band gap width and energy level position, the Sb 2 S 3 /Cd x Zn 1−x S heterojunction type can be regulated from Type-II to S-scheme. Photoelectrochemical (PEC) tests indicated that the composite photoanode Sb 2 S 3 /Cd 0.6 Zn 0.4 S achieved a higher photocurrent density (2.54 mA·cm−2, 1.23 V vs. RHE), which is about 4.31 times that of pure Sb 2 S 3 nanorod photoanode (0.59 mA·cm−2, 1.23 V vs. RHE). • Rod-like Sb 2 S 3 with [hk1] orientation is deposited on FTO substrate by VTD method. • The Sb 2 S 3 /Cd x Zn 1−x S heterojunction type can be regulated from Type-Ⅱ to S-scheme. • The S-scheme heterojunction could effectively promote PEC water splitting. • The photoelectrode exhibits considerable photocurrent 2.54 mA·cm−2 at 1.23 V RHE. [ABSTRACT FROM AUTHOR]

• Sb 2 S 3 NRs with high carrier transport were prepared by a novel epitaxial growth. • Novel Tm3+ doped strategy weakens the Fermi level pinning effect of Sb 2 S 3. • The enhanced PEC performance is attributed to the S-scheme mechanism. • The injection efficiency of the optimized photocathode was 81.7%. With the advantages of high absorption coefficient, non-toxicity and low cost, Sb 2 S 3 shows great potential as a narrow bandgap photocathode in the field of PEC hydrogen production. However, the separation and transportation of photogenerated carriers in the reported Sb 2 S 3 photocathode are inefficient due to its anisotropy and the Fermi level being pinned by deep-level defects. Therefore, Tm3+ doped Sb 2 S 3 nanorods with the selective carrier transport orientation were epitaxially grown on SnSe 2 film by a simple hydrothermal strategy to modulate the defect property of Sb 2 S 3 , optimize carrier transportation and separation efficiency, and improve the PEC performance of photoelectrodes. Experimental results showed that the doping of Tm3+ weakening the Fermi level pinning while achieving the conversion of Sb 2 S 3 to n-type conducting property. The S-scheme heterojunction formed by Tm3+ doped Sb 2 S 3 nanorods labeled as Sb 2 S 3 : Tm3+ and SnSe 2 nanosheets provided a stronger driving force to optimize carrier interface transportation. The photocurrent density (−0.91 mA cm−2) is increased about 18 times compared to the pristine Sb 2 S 3 photocathode. This work developed an effective doping strategy to weaken the Fermi level pinning and provided a novel idea for the epitaxial growth of Sb 2 S 3 nanorods to optimize the carrier transportation. [ABSTRACT FROM AUTHOR]

The charge generation mechanism of organic heterojunction (OHJ) consisted of 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) and different hole transporting materials (HTMs) are studied systematically by current-voltage (I–V) and capacitance-voltage measurements. The analysis of I–V characteristics of the devices based on OHJs at forward and reverse voltages by comparing the thickness of HTM layers finds that a forward and reverse symmetrical I–V curve is observed at thin HTM layers and the forward current becomes larger than the reverse current with the increase of HTM thickness, fully illustrating the effectiveness of OHJ charge generation. Moreover, the I–V characteristics at different temperatures indicate that the efficient charge generation is originated from electron tunneling rather than diffusion. And the C–V and capacitance-frequency (C–F)characteristics further illustrate the highly efficient charge generation ability of OHJs so that the charge density is as high as 4.5 × 1017 cm−3, guaranteeing the high conductivity of OHJs, which is very beneficial to developing highly efficient OLEDs using OHJs as charge injector and generator. The mechanism of charge generation in orgainc heterojunctions have been systematically studied via the analysis of I–V and C–V characteristics, which not only reveals that the highly efficient charge generation process is originated from the electron tunneling rather than the diffusion, but also exhibited the high charge density (4.5 × 1017 cm−3), ensure the high conductivity of OHJs. Image 1 • The charge generation process of OHJ is studied via the analysis of I–V and C–V characteristics. • The electron tunneling model of charge generation process is revealed. • The free charge density of OHJ is calculated as high as 4.5 × 1017 cm−3. [ABSTRACT FROM AUTHOR]

An efficient planar organic heterojunction (OHJ) consisted of 1,4,5,8,9,11-hexaazatriphenylene- hexacarbonitrile (HAT-CN)/1,1-bis [(di-4-tolyamino)phenyl)]cyclohexane (TAPC) is employed simultaneously as both charge generation layer (CGL) and charge injectors to fabricate high efficiency and long lifetime tandem organic light-emitting diodes (OLEDs). It can be seen that compared with conventional tandem OLEDs, the tandem OLEDs utilizing OHJ as both CGL and charge injectors significantly improved not only the current and quantum efficiencies, more importantly, but also the power efficiency and stability. The maximum efficiencies were as high as 42.0%, 159.5 cd A-1 and 92.7 lm W-1, and the lifetime reached 1350 h, which are more higher than the efficiencies of 34.3% 130.2 cd A-1 and 75.0 lm W-1 and the lifetime of 859 h of conventional tandem OLEDs. The more balanced charge generation and injection due to the simultaneous utilization of OHJ as CGL and charge injectors contributed to the significant improvement in the performance of resulting tandem OLEDs. These results fully indicate the validity of OHJ as CGL and charge injectors, and also provide a new route for the development of high performance OLEDs. High efficiency and long lifetime tandem OLEDs that utilize HAT-CN/TAPC (OHJs) as both charge generation layer (CGL) and charge injectors are fabricated, achieving a novel charge injection way, which is not only different from the injection via electrodes in traditional OLEDs, but also is benefical to realize the more balanced charge injection. Image 1 • Organic heterojunction HAT-CN/TAPC simultaneously as both charge generation layer and charge injectors is proposed. • High efficiency and long lifetime tandem OLEDs based HAT-CN/TAPC are successfully fabricated. • The more balanced charge generation and injection are realized in studied OLEDs. [ABSTRACT FROM AUTHOR]