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We present a multiscale method coupling the theory of open quantum systems with real-time ab initio treatment of electronic structure to study hot-carrier dynamics in photoexcited plasmonic systems. We combine the Markovian Stochastic Schrödinger equation with an ab initio GW coupled to the Bethe–Salpeter (BSE) equation description of the electronic degrees of freedom, interacting with a metallic nanoparticle modeled classically according to the polarizable continuum model. We apply this methodology to study the effect of relaxation (T1) and pure dephasing (T2) times on the hot-carrier dynamics in a system composed of a quantum portion described at GW/BSE level, i.e., a CHO fragment adsorbed on a vertex of a rhodium nanocube, and of the rest of the nanocube, treated classically, when irradiated with a 2.7 eV light pulse, inspired by the experimental results on plasmon-driven CO2 photoreduction. A net hole injection from rhodium to CHO is observed, with and without the classical portion of the nanocube. The nanocube effect is to enhance the generated charge population by two orders of magnitude. The nonradiative decay, via a relaxation time T1 based on the energy-gap law, produces a rapid decrease of the charge population. Results with T2 only show that a charge injection retarded with respect to the pulse, which is present in the coherent dynamics, disappears when coherence is erased. [ABSTRACT FROM AUTHOR]

This study investigates the stability of the (Hf,Zr)O2 (HZO) and AlScN thin films against the depolarization effect. In order to adversely interfere with the polarization screening of ferroelectric (FE) film and induce the depolarization effect, an Al2O3 film was inserted between the TiN bottom electrode and the FE film. Subsequently, to minimize charge injection through Al2O3 films, the double remanent polarization–voltage (2Pr–V) curve was measured employing voltage pulses with 1 μs-length. As the thickness of the Al2O3 film increased, the charge injection through the Al2O3 film decreased, leading to a decrease in the slope of the 2Pr–V curve. The magnitude of the depolarization field applied to the FE film was determined by simulating the 2Pr–V curve using an equivalent circuit model. Subsequently, the proportion of reversed domains during the delay period due to the depolarization effect was measured. It was revealed that HZO films exhibited vulnerability to the depolarization effect, with 16% of domains being reversed. On the other hand, AlScN films demonstrated superior stability, with polarization loss of less than 1%. Ultimately, it was revealed that AlScN films demonstrated superior stability against the depolarization effect compared to HZO films due to their higher coercive field and more uniform polarization distribution across the film area. [ABSTRACT FROM AUTHOR]

Amorphous composite polymers are widely used as insulators in microelectronics due to their high dielectric strength, mechanical robustness, and thermal stability. However, organic–inorganic composite systems suffer from undesirable performance and accelerated degradation due to leakage current ( J Tot ). Unfortunately, the underlying mechanism of J Tot and its components (e.g., ionic and electronic constituents) are inadequately understood, particularly in extreme use conditions (e.g., high humidity and temperature). In this study, we use numerical simulation and experimental J Tot data (in amorphous epoxy polymer with silica fillers) to (i) unify the electrostatic model for J Tot in composite polymers, (ii) illustrate that the early part of J Tot (i.e., external current) is primarily due to the image charge associated with ion transport/ localization ( J ion ) near the metallic contacts, (iii) demonstrate that the accumulated counter-ions reduce the barrier for electronic charge injection (by band bending) and facilitate electronic injection from the metals ( J elec ), and (iv) provide an algorithm for the in situ ion transport characterization of composite insulators by exploiting J ion . This work provides new insights regarding the leakage current mechanism and how it can be used as a probe into the complex transport mechanisms of the composite material. [ABSTRACT FROM AUTHOR]

Charge injection at metal/polymer interfaces is a critical process in many technological devices, including high voltage capacitors and cables in which polyolefin materials, such as polyethylene (PE) and polypropylene (PP), are often used as insulation materials. We use simulations based on density-functional theory to study charge injection at aluminum/PE and aluminum/PP interfaces. Specifically, we investigate the influence of incorporating a variety of polar chemical impurities at the PE and PP chain ends on electron and hole injection barriers. Crucially, we account for the effect of thermal disorder by considering ensembles of thousands of interface structures obtained from ab initio molecular dynamics trajectories at 373 K. We show that the mean injection barrier can change by up to 1.1 eV for Al/PE and 0.6 eV for Al/PP, as compared to the pristine case, depending on which chemical impurity is introduced. We also show that the spread of injection barriers from thermal fluctuations also depends strongly on the chemistry of the impurity. The observed trends can be understood with a simple model based on thermal fluctuations of the dipole moment density associated with the chemical impurity at the interface. We further verify this model by considering larger interface models with lower impurity densities. Our results demonstrate that small chemical modifications, which may arise from oxidation, for example, have a significant influence on charge injection barriers in metal/polyolefin interfaces. [ABSTRACT FROM AUTHOR]

The demand for reliable memory devices capable of operating in harsh environments, such as space and vehicles, necessitates the development of high-temperature-resistant technologies. In this study, we propose a novel ferroelectric domain wall (DW) memory utilizing BiFeO3 thin films, which exhibit exceptional retention and fatigue properties at 135 °C. Achieving this performance was made possible through precise control of the oxygen vacancy density in the epitaxial thin films induced by a post-annealing procedure conducted under an appropriate oxygen pressure of 10 Pa. Initially, prototype nano-memory devices lacking post-annealing treatment demonstrated resistive switching behavior at room temperature, with a current rectification ratio of 100:1, achieved by manipulating the uncompensated DW induced by polarization switching. With the additional annealing procedure in lower oxygen pressure, the wall current magnitude of the devices increased significantly, indicating the critical role of the oxygen vacancies in modulating the DW conductivity. Moreover, the nanodevices exhibited improved polarization retention due to oxygen vacancy-mediated charge injection that can be further enhanced at the elevated temperature. The electrons trapped deeply at the artificial DW were found to stabilize the switched polarization at the expense of reduced DW conductivity, emphasizing the importance of precise control over oxygen vacancy density for achieving a balance between high DW conductivity and excellent polarization retention. [ABSTRACT FROM AUTHOR]

In this paper, a method of significantly increasing the energy density of biaxially oriented polypropylene (BOPP) film by cryogenic environment has been proposed. The notable enhancements in the dielectric and energy storage performance can be attributed to precise microstructure manipulation, aimed at controlling charge injection limitations and optimizing molecular chain dynamics. The experimental results show that the maximum discharged energy density of BOPP film with thicknesses of 3.4 μw m has reached 11.83 J cm−3 at −196 °C (2.9 times that at 25 °C) with a charge-discharge efficiency of 92.74%. The direct current breakdown strength as high as 1120.4 kV mm−1 is obtained at −196 °C, exhibiting a substantial 63.7% augmentation compared to the measurement at 25 °C. Furthermore, reductions in conductance loss and capacitance loss (post self-healing testing) are realized. Mechanistic insights into the observed enhancements are investigated through computational simulations. This research provides a pivotal advancement and valuable perspective towards the development of film capacitors boasting the excellent energy storage characteristics. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an ultrahigh input impedance, low noise, and wide bandwidth four‐channels analog front‐end (AFE) for low‐power neural recording systems. To achieve high input impedance, the buffer channels are placed between the electrodes and the main amplifier stage of the AFE. The buffer is designed with low noise and low power consumption to obtain high input impedance of overall AFE while maintaining low input‐referred noise and low power consumption. A chopper capacitively coupled chopper instrumentation amplifier (CCIA) is placed after the buffer as the main amplifier stage of the AFE to improve the common mode rejection ratio (CMRR) and the input‐referred noise of the overall AFE design. A new chopper stabilization control technique is proposed and used in the CCIA stage to reduce the charge injection and clock feedthrough and consequently the high‐frequency ripple of the AFE output signal. A programmable gain amplifier (PGA) is designed as the third stage to adjust the overall gain of the AFE. Benefiting from PGA, the AFE can adapt its gain with both action potential and local field potential signals. To reduce the number of the electrode to be implanted and reduce the impedance mismatch that causes the degradation on overall CMRR performance, two AFE channels shared a reference electrode followed by a reference buffer. The proposed AFE is designed and simulated using a standard 180 nm CMOS process and operates in a wide frequency band of 2.1 to 2500 Hz with low input‐referred noise of 1.6 μVrms and a CMRR over 80 dB at 2.1 Hz. The total power consumption is lower than 4.3 μW per channel. With the proposed structure of AFE, the input impedance is 35 GΩ @ 21 Hz and the minimum impedance over operational bandwidth is 75 MΩ @ 2.5 kHz. [ABSTRACT FROM AUTHOR]

Highly efficient charge injection and charge trapping stability of the tunneling layer are of desirable and practical importance to transistor memory applications. However, both of which can be contradictory to the nature properties of its material. It is herein demonstrated that lowering the energy mismatch of the tunneling layer by employing a longer conjugation length of the polymer can improve the charge injection efficiency, albeit the trapped charges will be easily diminished and finally losing its memory characteristics, and vice versa. To further elaborate and verify this concept, both materials are blended with distinct nature of properties as the tunneling layer in pentacene‐based transistor devices. As the results, the device using 300 nm SiO2 with optimum blending ratio displays a broad memory window of ≈77.6 V which is superior to the non‐blended tunneling layer carrying appropriate energy levels and band gap energy, not to mention, revealing fast operation time (≈1 s), low driving voltage (≈20 V), long retention (>104 s), and high switching stability over 50 cycles with on–off ratio of >104. Most importantly, this finding shed insight into the design of tunneling materials for advancing organic transistor memory technologies based on tunneling‐effect‐boosted interfacial charge trapping. [ABSTRACT FROM AUTHOR]

Fluorine‐doped tin oxide (FTO) substrate is an important and expensive component in perovskite solar cells (PSCs), which accounts for up to 40 % of a typical PSC raw material cost. In this study, we investigated the recyclability of SnO2/FTO in PSCs by washing the spent PSCs using different solvent such as dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetone, water, and acetone/water mixture. Characterisation of properties of the SnO2/FTO substrates recovered from the PSC show the surface wettability of SnO2/FTO is largely unchanged with water washing while a higher hydrophobicity is obtained with organic solvent washing. Comparison of electronic properties of the SnO2/FTO substrate shows a downward shift of the conduction band by 180 meV with water washing, creating favourable energy alignment with adjacent perovskite for efficient interfacial charge injection. Consequently, PSCs using the water‐based recycled SnO2/FTO substrates produced a high power conversion efficiency (PCE) of 19.33 % which is comparable to the device using fresh SnO2/FTO substrate (PCE=19.85 %). Furthermore, we demonstrated that the water washing process could retain property of SnO2/FTO substrate for decent PSC performance up to four recycling cycles. This study opens new avenues towards recycling of valuable FTO substrates in PSCs for increased sustainability and cost‐effectiveness. [ABSTRACT FROM AUTHOR]

Polymers containing π-conjugated segments are a diverse group of large molecules with semiconducting and emissive properties, with strong potential for use as active layers in Organic Light-Emitting Diodes (OLEDs). Stable blue-emitting materials, which are utilized as emissive layers in solution-processed OLED devices, are essential for their commercialization. Achieving balanced charge injection is challenging due to the wide bandgap between the HOMO and LUMO energy levels. This study examines the optical and photophysical characteristics of blue-emitting polymers to contribute to the understanding of the fundamental mechanisms of color purity and its stability during the operation of OLED devices. The investigated materials are a novel synthesized lab scale polymer, namely poly[(2,7-di(p-acetoxystyryl)-9-(2-ethylhexyl)-9H-carbazole-4,4′-diphenylsulfone)-co-poly(2,6-diphenylpyrydine-4,4′-diphenylsulfone] (CzCop), as well as three commercially supplied materials, namely Poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO), poly[9,9-bis(2′-ethylhexyl) fluorene-2,7-diyl] (PBEHF), and poly (9,9-n-dihexyl-2,7-fluorene-alt-9-phenyl-3,6-carbazole) (F6PC). The materials were compared to evaluate their properties using Spectroscopic Ellipsometry, Photoluminescence, and Atomic Force Microscopy (AFM). Additionally, the electrical characteristics of the OLED devices were investigated, as well as the stability of the electroluminescence emission spectrum during the device's operation. Finally, the determined optical properties, combined with their photo- and electro-emission characteristics, provided significant insights into the color stability and selectivity of each material. [ABSTRACT FROM AUTHOR]

Light‐emitting transistors (LETs) are a remarkable, emerging class of electronic devices that combine the switching function of field‐effect transistors (FETs) and the light‐emitting function of light‐emitting diodes (LEDs). In order to achieve efficient light emission, effective electron and hole injection from source and drain electrodes is necessary. Various strategies have been introduced to accomplish this, such as incorporating asymmetric electrodes or charge injection layers during device fabrication. These approaches have inevitably introduced complexity in the device fabrication process. Herein, light‐emitting electrochemical transistors (LECTs) are demonstrated that combine principles of electrochemistry and optoelectronics to achieve multi‐functionality in a simple device architecture. Hybrid polyelectrolytes, poly(9‐vinylcarbazolesulfonate)‐ lithium and copper (II) salts (PVK‐Li and PVK‐Cu) incorporating Li+ ion and Cu2+ ions are added at variable concentrations to the organic emitting layer of LECTs to effect electrochemical p‐type doping. This electrochemical doping approach yielded improvements in electrical and optical performances including mobilities, brightnesses, and external quantum efficiency of the LECTs. The dynamics of how charges including ions, electrons, and holes move and interact are discussed in the device to facilitate emissive charge carrier recombination and light emission. This investigation provides valuable insights into the realms of both electrochemistry and optoelectronics. [ABSTRACT FROM AUTHOR]

Lead halide perovskite nanocrystals are attractive for light emitting devices both as electroluminescent and color‐converting materials since they combine intense and narrow emissions with good charge injection and transport properties. However, while most perovskite nanocrystals shine at green and red wavelengths, the observation of intense and stable blue emission still remains a challenging target. In this work, a method is reported to attain intense and enduring blue emission (470–480 nm), with a photoluminescence quantum yield (PLQY) of 40%, originating from very small CsPbBr3 nanocrystals (diameter < 3 nm) formed by controllably exposing Cs4PbBr6 to humidity. This process is mediated by the void network of a mesoporous transparent scaffold in which the zero‐dimensional Cs4PbBr6 lattice is embedded, which allows the fine control over water adsorption and condensation that determines the optimization of the synthetic procedure and, eventually, the nanocrystal size. The approach provides a means to attain highly efficient transparent and stable blue light‐emitting films that complete the palette offered by perovskite nanocrystals for lighting and display applications. [ABSTRACT FROM AUTHOR]

The construction of miniaturized light-emitting diodes (LEDs) with high external quantum efficiency (EQE) at room temperature remains a challenge for on-chip optoelectronics. Here, we demonstrate microsized LEDs fabricated by a dry-transfer van der Waals (vdW) integration method using typical layered Ruddlesden-Popper perovskites (RPPs). A single-crystalline layered RPP nanoflake is used as the active layer and sandwiched between two few-layer graphene contacts, forming van der Waals LEDs (vdWLEDs). Strong electroluminescence (EL) emission with a low turn-on current density of ~20 pA μm-2 and high EQE exceeding 10% is observed at room temperature, which sets the benchmark for the EQE of vdWLEDs ever recorded. Such efficient EL emission is attributed to the inherent multiple quantum well structure and high photoluminescence quantum yield (~35%) of RPPs and a low charge injection barrier of ~0.10 eV facilitated by the Fowler-Nordheim tunneling mechanism. These findings promise a scalable pathway for accessing high-performance miniaturized light sources for on-chip optical optoelectronics. [ABSTRACT FROM AUTHOR]

This study proposes a novel 6-transistor bootstrapped switch with minimized sampling and holding error obtained through sampling window error analysis for SAR ADC design. The proposed switch design strategically mitigates channel charge injection and minimizes the input signal dependency of on-resistance by optimizing its sizing parameters. To counteract channel charge effects, dummy NMOS and PMOS components are judiciously employed, culminating in a substantial improvement in the effective number of bits (ENOB). The complete analysis of the proposed circuit is done using the Cadence Virtuoso SCL 0.18 μ m CMOS process. For a 51.514 kHz sinusoidal 1 V peak-to-peak differential input signal with a 1 MSPs clock speed, the proposed circuit achieves 2.0141 mV maximum sampling window error, 0.131 μ W power consumption, 84.67 dB signal-to-noise ratio (SNR), 84.67 signal-to-noise and distortion (SINAD) ratio and 86.02 dB spurious-free dynamic range (SFDR), which produces 13.77 bits ENOB. For the impacts of process variations and mismatch on switch performance, a comprehensive 500-point Monte Carlo (MC) simulation of the proposed bootstrap switch is conducted in this study. Post-layout results show that the proposed circuit is suitable for IoT applications. [ABSTRACT FROM AUTHOR]

The crystal structure has a great influence on the dielectric and piezoelectric performance of poly(vinylidene fluoride) (PVDF). In this work, we prepared PVDF films with two typical crystalline phases (α and β). In situ Kelvin probe force microscopy (KPFM) and Piezoelectric force microscopy (PFM) were employed to investigate the responses of different PVDF crystalline phases to charge mobility, polarization, and piezoelectric properties. We used a homemade Kelvin probe force microscope (KPFM) to inject charges into the two crystalline phases to investigate the differences in the response of different crystalline phases of PVDF to electrical excitation on a microscopic scale. It was found that the α-phase has a lower charge injection barrier and is more susceptible to charge injection and that the α-phase is accompanied by a faster charge dissipation rate, which makes it easier to accumulate charge at the interface between the α-phase and β-phase PVDF. Moreover, the PFM polarization manipulation showed no change in the amplitude and phase diagram of the α-phase under ±10 V bias. In contrast, the β-phase showed a clear polarization reversal phenomenon and a significant increase in piezoelectric amplitude, which is consistent with its polar intrinsic properties. This study provides valuable insights into the multiphase contributions and a reference for designing advanced PVDF dielectrics. [ABSTRACT FROM AUTHOR]

Photoadaptive neuromorphic device is fundamental for artificial vision system to effectively perceive and accurately process information in complex light scenes. However, adaptive optoelectronic device remains a challenge due to the difficulty in achieving the light‐dependent modulation of charge dynamics. Here, an adaptive optoelectronic transistor enabled by the conformal nanoporous patterning that can perform the biomimetic eye functions and facilitate the precise contrast enhancement under harsh lighting conditions is reported. The enhanced light absorption, photoexciton separation, and charge injection properties are originated from the localized electric field in the nanoporous optoelectronic transistor, which further endow the light intensity‐dependent charge trapping and de‐trapping dynamics, realizing the adaptive decay rate of conduction states. Based on the improved device performances and the adaptive properties, an artificial vision system is constructed to present the biomimetic eye model with visual selective attention functions and a contrast enhancement in the low‐contrast sub‐images. The eye rotation and closing functions, as well as a high recognition accuracy of 95.4% for non‐ideal image with a contrast as low as 0.8% are demonstrated. This study provide an approach for the photoadaptive neuromorphic device and support their visual adaptation applications in biomimetic eye system. [ABSTRACT FROM AUTHOR]

The photoelectrochemical performance of Ta3N5 photoanodes is strongly impacted by the presence of shallow and deep defects within the bandgap. However, the role of such states in defining stability under operational conditions is not well understood. Here, a highly controllable synthesis approach is used to create homogenous Ta3N5 thin films with tailored defect concentrations to establish the relationship between atomic‐scale point defects and macroscale stability. Reduced oxygen contents increase long‐range structural order but lead to high concentrations of deep‐level states, while higher oxygen contents result in reduced structural order but beneficially passivate deep‐level defects. Despite the different defect properties, the synthesized photoelectrodes degrade similarly under water oxidation conditions due to the formation of a surface oxide layer that blocks interfacial hole injection and accelerates charge recombination. In contrast, under ferrocyanide oxidation conditions, it is found that Ta3N5 films with high oxygen concentrations exhibit long‐term stability, whereas those possessing lower oxygen contents and higher deep‐level defect concentrations rapidly degrade. These results indicate that deep‐level defects result in rapid trapping of photocarriers and surface oxidation but that shallow oxygen donors can be introduced into Ta3N5 to enable kinetic stabilization of the interface. [ABSTRACT FROM AUTHOR]

BiFeO 3 -BaTiO 3 (BF-BT) ceramics are an excellent choice for high-temperature lead-free piezoelectric ceramic due to their high Curie temperature and good piezoelectric properties, but the volatilization of Bi leads to the formation of A-site cationic vacancies and oxygen vacancies, culminating in heightened leakage currents and detrimental effects on piezoelectric properties. In this study, a chemical composition of 0.70Bi (1+ x) Fe 0·97 Al 0·03 O 3 -0.30BaTiO 3 ceramics, abbreviated as B 1+ x FA-BT, where 0 ≤ x ≤ 0.05, were synthesized, with special attention on the effects of Bi compensation and poling process on their insulation and piezoelectric properties. Due to the coexistence of R - PC phases and low leakage current, B 1+ x FA-BT ceramics exhibit excellent piezoelectric properties and high Curie temperature, among which the B 1.02 FA-BT ceramic boasts optimal overall properties: d 33 = 196 pC N−1, T C = 480 °C, k p = 34%, θ max = 49.5° and Q m = 32, under optimal poling parameters E p = 50 kV cm−1 and T p = 100 °C. The poling process is directly linked to the reorientation of domains, the redistribution of positive/negative space charge and the aggregation or injection of holes, which is achieved by tuning the poling field and temperature in a ceramic with optimal integrated piezoelectric properties. The poling process of BF-BT ceramics is significantly influenced by their leakage characteristics, which can have a significant impact on their overall performance. Optimizing electrical poling conditions and minimizing leakage current is crucial to achieving favorable piezoelectric properties in BF-BT ceramics with R - PC coexisting structures. [ABSTRACT FROM AUTHOR]

The cathode interface layers (CILs) play a crucial role in enhancing the performance of organic solar cells (OSCs). However, challenges arise due to the high work function of CIL and inadequate contact with the active layer, leading to high interface trap recombination and poor charge extraction. In this study, a novel approach is proposed to improve charge injection and extraction in CILs by incorporating polyphenols, trihydroxybenzoic acid (TBA). Focusing on the CIL PDINN, its work function is successfully reduced from 4.14 eV to 3.80 eV and obtained charge collection efficiency of 91.23% through TBA regulation. These enhancements can be ascribed to improved contact between the active layer and the CILs, and enhanced the formation of a fine fiber phase width and inhibited interface recombination. As a result, the power conversion efficiency (PCE) of the binary OSCs comprising PM6: BTP‐ec9 exhibits an increase from 18.2% to 19.3%, placing it among the one of the highest PCE values. Moreover, this approach demonstrated notable applicability for another CILs, as well as various OSCs systems. Overall, this research underscores the importance of regulating and modifying CILs to fully exploit their potential in OSCs devices, while laying the groundwork for optimizing their efficiency and stability. [ABSTRACT FROM AUTHOR]

Dielectric capacitors play a pivotal role in the advancement of electric power systems and emerging energy technologies. However, the deterioration of dielectric performance in energy storage materials at elevated temperatures represents a significant challenge. In this study, organic electron‐scattering agents into polyetherimide (PEI) are introduced, creating a "peaked barrier" to impede charge carrier transport. By doping PEI with an ultralow volume fraction (0.8%) of the organic molecule filler 4‐(dimethylamino)phenylboronic acid (4‐NB), the electron‐repelling nature of 4‐NB is leveraged in order to regulate charge carrier injection and transport in a synergistic manner. Consequently, the discharged energy density of the PEI composite material increases to 7.93 J cm−3 (720 kV mm−1) at 30 °C. At 150 °C, the discharged energy density increases to 5.21 J cm−3 (580 kV mm−1). In both cases, the charge and discharge efficiencies are maintained at 90%. It is noteworthy that the prepared PEI composite material also exhibits excellent charge dissipation characteristics, maintaining stable charge and discharge efficiency even after 50 000 charge–discharge cycles. In summary, the study's design concept systematically optimizes the processes of charge carrier injection, transport, and dissipation. This approach offers a novel perspective for the development of dielectrics that are suitable for long‐term energy storage. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) hydrogen evolution from water splitting of semiconductor photoanodes is intricately linked to their light‐absorbing capacity, surface reaction kinetics, bulk charge carrier separation efficiency, and surface charge carrier injection efficiency. Harnessing the surface plasmon resonance effect of metals emerges as a promising approach to enhance PEC performance of semiconductor photoanodes. This work presents the first application of non‐noble metal Al nanoparticles to sensitize a BiVO4 nanoporous film (NPF) photoanode. This process significantly expedites the surface kinetics of water oxidation, and improves both bulk charge carrier separation and surface carrier injection efficiencies of BiVO4 NPF photoanode. Additionally, the surface‐formed Al2O3 film effectively preserves the stability of photoanode, leading to a substantial improvement in PEC hydrogen evolution of BiVO4 NPF photoanode in a three‐electrode PEC cell with sulfite scavenger. The constructed BiVO4/Al NPF heterojunction photoanode exhibits a hydrogen evolution rate of 73.9 µmol cm⁻2 h⁻¹ at 1.23 V versus reversible hydrogen electrode, 1.68 times of BiVO4 photoanode. Additionally, BiVO4/Al NPF photoanode exhibits excellent stability under long‐time light irradiation of 8 h. This study provides valuable insights into the design of nonnoble‐metal‐based plasmonic photoanodes for efficient hydrogen generation through PEC cell from the perspectives of surface reaction kinetics, charge carrier injection, and separation. [ABSTRACT FROM AUTHOR]

In the landscape of photovoltaic research, carbon‐based perovskite solar cells (C‐PSCs) have attracted widespread attention due to their outstanding stability. However, compared to metal‐based PSCs, their power conversion efficiency (PCE) lags markedly behind. The key lies in two primary factors: First, the inefficiency of the carbon electrode in transporting and collecting carriers; second, the energy level mismatch with adjacent functional layers. These problems increase both the charge transport resistance and the charge injection barriers, thereby diminishing the overall efficiency of the device. In this study, an effective strategy is presented to tackle this issue by developing modular C‐PSCs that utilize dual carbon electrodes and implement multiscale modulation. This approach specifically focuses on three crucial aspects: establishing a highly conductive network, ensuring sufficient interfacial contact, and achieving well‐matched energy band alignment. By synergistically incorporating 0D carbon black (CB) and 1D carbon nanotube (CNT) into dual carbon electrodes, a resilient conductive network with enhanced interfacial contact is established, creating favorable conditions for efficient carrier transfer. Additionally, the energy level structure of CB is meticulously adjusted at the molecular scale by introducing individually adsorbed titanium (Ti) atoms, effectively addressing the energy level mismatch with the hole transport layer (spiro‐OMeTAD), and notably reducing the charge injection barrier at the interface. Based on the above strategy, the PCE of the C‐PSCs has undergone a remarkable enhancement from 15.27% to 22.45%. Moreover, the device shows excellent stability, with its PCE retaining over 95% of the initial value even after 1000 h of continuous operation under one‐sun intensity. [ABSTRACT FROM AUTHOR]

The bandgap and operation stability of metal halide perovskites (MHPs) based light‐emitting diodes (PeLEDs) have been compromised by the substantial surface defect densities in the matrix. Today's defect passivation strategies rely on coordination actions of small‐molecular and/or polymeric ligands, which effectively enhance the optical properties of materials. However, the non‐trivial insulating characteristics of the molecules concurrently sacrifice the operation stability and external quantum efficiency (EQE) of the PeLEDs by augmenting the charge injection barrier at the interface. Herein, a coordinative, charge‐polarized organic semiconductor exhibiting thermally activated delayed fluorescence (TADF), namely 9,9‐dimethyl‐10‐(4‐(phenyl sulfonyl)phenyl)‐9,10‐dihydroacridine (SO‐DMAc) is coordinated, into the MHPs matrix for deep‐red PeLEDs. Owing to the distinctive charge transfer (CT) between the molecule and MHPs with exclusive coordination at the MHP's bottom, SO‐DMAc serves as a molecular bridge that significantly augments the hole injection into the PeLEDs. Encouraged by these improvements, efficient and stable deep red PeLEDs offering EQE of 21.8% and respective half lifetimes (T50) of luminance and EQE exceeding 6 and 35 h are demonstrated. It is revealed that the molecular coordination to the MHP surface is pivotal to manifesting the interfacial CT process for favorable energy level tuning. [ABSTRACT FROM AUTHOR]

Electric heaters based on functional materials and innovative designs have been developed for various applications. In this paper, we propose a soft dielectric heater (SDH) using polyvinyl chloride-gel (PVC-gel) as the dielectric heater and hydrogel as stretchable electrodes. Under an AC voltage, the leakage current in the PVC-gel leads to continuous injection and discharge of charges, causing the polarized plasticizers and flexible PVC chains to vibrate and collide, thereby generating heat through dielectric heating. Furthermore, the SDH generates a uniform temperature distribution even under strains up to 400%. Besides, high transmittance over 86% across the visible range renders it suitable for wearable or skin-mountable heaters from an esthetic viewpoint. Its capacitor-like structure achieves a scalable design, enabling extension from a singular cell to a row/column addressable and pixelated array of heaters. The 5 × 5 SDH array can deliver varied thermal information and sensations while maintaining performance even when stretched. [ABSTRACT FROM AUTHOR]

Modifying photoanodes with metal-organic frameworks (MOFs) as oxygen evolution reaction (OER) cocatalysts has emerged as a promising approach to enhance the efficiency of photoelectrochemical (PEC) water oxidation. However, designing OER-active MOFs with both high photo- and electrochemical stability remains a challenge, limiting the advancement of this research. Herein, we present a facile method to fabricate a MOF-modified photoanode by directly loading a pentanuclear Co-based MOF (Co-MOF) onto the surface of a Ti-doped hematite photoanode (Ti:Fe2O3). The resulting Co-MOF/Ti:Fe2O3 modified photoanode exhibits an enhanced photocurrent density of 1.80 mA · cm-2 at 1.23 V, surpassing those of the Ti:Fe2O3 (1.53 mA · cm-2) and bare Fe2O3 (0.59 mA · cm-2) counterparts. Additionally, significant enhancements in charge injection and separation efficiencies, applied bias photon-to-current efficiency (ABPE), incident photon to current conversion efficiency (IPCE), and donor density (Nd) were observed. Notably, a minimal photocurrent decay of only 5% over 10 h demonstrates the extraordinary stability of the Co-MOF/Ti:Fe2O3 photoanode. This work highlights the efficacy of polynuclear Co-based MOFs as OER cocatalysts in designing efficient and stable photoanodes for PEC water splitting applications. [ABSTRACT FROM AUTHOR]

2D metal and semiconductor materials provide a promising solution to realize Ohmic contacts by suppressing the strong Fermi level pinning (FLP) effect due to without dangling bonds. However, the 2D metal‐semiconductor Van der Waals (vdW) interfaces induce an inevitable tunnel barrier, significantly restraining the injection of charge carriers into the conduction channel. Herein, by replacing the vdW bond with the covalent bond in interfaces, the Ohmic and tunneling‐barrier‐inhibition contacts are realized simultaneously based on the 2D XSi2N4 (X = Cr, Hf, Mo, Ti, V, Zr) semiconductor and the 2D Mxene metal family. Taking 60 2D Mxene‐XSi2N4 contacts as examples, although the vdW‐type contacts exhibit Ohmic contacts, the tunneling probability (PTB) can be as low as 0.4%, while the PTB can increase to 88.09% by removing the Mxene terminations at the adjacent interface to form the covalent bond. The weak FLP and Ohmic contacts are retained at covalent bond interfaces since the outlying Si─N sublayer protects the band‐edge electronic states of XSi2N4 semiconductors. This work provides a straightforward strategy for advancing high‐performance and energy‐efficient 2D electronic nanodevices. [ABSTRACT FROM AUTHOR]

Near‐infrared organic photodetector (NIR OPD) is promising for emerging wearable biosensing applications. However, their practical application is hindered by the high dark currents of devices that limit the detection of faint light. In this work, highly sensitive flexible NIR OPDs are presented with ultralow dark currents, fabricated using a layer‐by‐layer blade coating (LBL‐BC) technique. In the active layer, a fully fused‐ring molecule FM2, featuring a fixed molecular skeleton, is employed as an electron acceptor to reduce the trap density. The LBL‐BC method enhances the film order and phase purity of the active layer, significantly reduces the trap density of states, and optimizes the vertical phase separation structure of the thin film, thereby preventing reverse charge injection. As a result, a highly sensitive flexible NIR OPD is developed exhibiting an ultralow dark current density of 4.83 × 10−9 A cm−2 at −0.3 V bias and an extremely low noise current density of 7.65 × 10−15 A Hz−1/2 at 10 Hz, comparable to commercial silicon photodiodes. Furthermore, this flexible device is successfully applied for real‐time monitoring of human heartbeat rate, oxygen saturation, and motion recognition. These findings advance the development of highly sensitive NIR OPDs and their application in wearable biosensing technologies. [ABSTRACT FROM AUTHOR]

Efficient p‐ and n‐type in situ doping of compressively strained germanium tin (Ge1‐xSnx) semiconductor epilayers, grown by chemical vapor deposition on a standard Si(001) substrate, is demonstrated. Materials characterization results reveal unusual impact of dopants manifesting via a pronounced reduction of Sn content in the epilayer, accompanied by an enhancement of the growth rate, due to increasing p‐type doping concentration. Furthermore, the opposite behavior for n‐type doping is observed, resulting in a less pronounced increase of Sn concentration and no effect on growth rate. Nevertheless, a very high density of electrically active holes up to ≈4 × 1020 cm−3 is obtained in p‐type doped Ge1‐xSnx epilayer resulting in the lowest resistivity of 0.15 mΩ cm among all in situ doped epitaxial and strained group‐IV semiconductors. Also, the metal‐to‐insulator transition in Ge1‐xSnx is experimentally demonstrated for doping levels above 1 × 1017 cm−3, which is substantially lower than in any group‐IV semiconductor, and theoretically predict it to be as low as ≈1 × 1017 cm−3. The findings enabled by the doping regime explored in this work can open novel prospects to engineer low resistivity contacts and charge current injection in applications covering next‐generation transistors, qubits, diodes, electrically driven light sources, sensors and hybrid quantum devices. [ABSTRACT FROM AUTHOR]

The charge carrier mobility in tris(4‐carbazoyl‐9‐ylphenyl)amine (TCTA), a host and hole transport material typically used in organic light‐emitting diodes (OLEDs), is measured using charge carrier electrical injection metal–insulator–semiconductor charge extraction by linearly increasing voltage (i‐MIS‐CELIV). By employing the injection current i‐MIS‐CELIV method, charge transport at time scales shorter than the transit times typically observed in standard MIS‐CELIV is measured. The i‐MIS‐CELIV technique enables the experimental measurement of unequilibrated and pretrapped charge carriers. Through a comparison of injection and extraction current transients obtained from i‐MIS‐CELIV and MIS‐CELIV, it is concluded that hole trapping is negligible in evaporated neat films of TCTA within the time‐scales relevant to the operational conditions of optoelectronic devices, such as OLEDs. Furthermore, photocarrier generation in conjunction with i‐MIS‐CELIV (photo‐i‐MIS‐CELIV) to quantify the properties of charge injection from the electrode to the semiconductor of the MIS devices is utilized. Based on the photo‐i‐MIS‐CELIV measurements, it is observed that the contact resistance does not limit the injection current at the TCTA/molybdenum oxide/silver interface. Therefore, when TCTA is employed as the hole transport/electron‐blocking layer in OLEDs, it does not significantly reduce the injection current and remains compatible with the high injection current densities required for efficient OLED operation. [ABSTRACT FROM AUTHOR]

In this paper, the instability of two layers of insulating and conducting immiscible liquids separated by a deformable interface and subjected to unipolar injection is examined. Taking into account the slight deformation of the interface between the two liquids, a system of equations and boundary conditions is derived at marginal state. Non zero numerical solutions for both layers exist only for eigenvalues of the instability parameter T, which depends on the following parameters: injection level C, Bond number Bo, a new non-dimensional parameter P proportional to interfacial tension and the ratio of the layers' thickness and of liquids viscosity. The variations in the instability criterion Tc, corresponding to the smallest eigenvalue, are examined in detail as a function of the main characteristic parameters C, P and the Bond number. We find that for some values of P, two instability mechanisms convective and interfacial ones can take place. When the strength of interfacial tension or the liquid thickness ratio is very low, the critical number tends to a value corresponding to interfacial instability. The influence of injection-induced convection in the insulating layer and the effect of interfacial deformation on interfacial instability are also discussed. [ABSTRACT FROM AUTHOR]

This article investigates the behavior of two parallel layers of different miscible dielectric liquids enclosed and sandwiched between two electrodes. By applying an electric potential to one electrode while grounding the other, electro-convection occurs when the electric Rayleigh number exceeds a critical value, setting the fluid into motion and resulting in rapid mixing between the two liquids. A numerical model is developed to account for the varying ionic mobility and permittivity of the two liquids, considering their evolution based on the relative concentration field. The simulations confirm that electro-convection significantly enhances the mixing between the two liquids, as expected. Additionally, intriguing ripples are observed near the initial interface during the early stages of electro-convection instability growth. To explain and describe the flow dynamics in terms of stability analysis, a semi-analytical model is presented. This study provides insights into the mixing behavior and flow dynamics of miscible dielectric liquids under the influence of electro-convection. The findings contribute to a better understanding of the underlying mechanisms and can be valuable for applications such as microfluidics, energy conversion, and mixing processes. Further research is encouraged to explore additional parameters and optimize the control of electro-convection for practical applications. [ABSTRACT FROM AUTHOR]

Organic Light-Emitting Diodes (OLEDs) require several organic layers, including carrier injection layers, charge transport layers, and light-emitting layers (EML). Recently, many panel companies have been using layers with a dual function of charge transport and blocking to simplify the layer structure. At the same time, efficient charge injection into the EML is required to improve the device characteristics. In particular, the hole injection properties are important in devices using phosphorescent emitters because it is a major factor in forming the broad recombination zone. This study reports the factors influencing the device performances using three OLEDs with different electron-blocking layers (EBL). By adjusting the EBL's energy levels, it is possible to form a broad recombination zone and reduce hole accumulation and polaron-induced stress at the interface. In addition, the wide dispersion of exciton formation reduces the overcrowding of exciton which induces exciton quenching and relieves an efficiency roll-off at high luminance. Consequently, the external quantum efficiency of N-([1,1'-biphenyl]-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-11,11-dimethyl-11H-benzo[b]fluoren-3-amine with a relatively deep HOMO level is increased by more than 2% with a relaxed roll-off of 7% at 3000 cd/m2 and a device lifetime is increased fivefold compared to those of N-([1,1′-biphenyl]-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-11,11-dimethyl-11H-benzo[b]fluoren-2-amine with a relatively shallow HOMO level. [ABSTRACT FROM AUTHOR]

Nonlocal spin polarization phenomena are thoroughly investigated in the devices made of chiral metallic single crystals of CrNb3S6 and NbSi2 as well as of polycrystalline NbSi2. We demonstrate that simultaneous injection of charge currents in the opposite ends of the device with the nonlocal setup induces the switching behavior of spin polarization in a controllable manner. Such a nonlocal spin polarization appears regardless of the difference in the materials and device dimensions, implying that the current injection in the nonlocal configuration splits spin-dependent chemical potentials throughout the chiral crystal even though the current is injected into only a part of the crystal. We show that the proposed model of the spin dependent chemical potentials explains the experimental data successfully. The nonlocal double-injection device may offer significant potential to control the spin polarization to large areas because of the nature of long-range nonlocal spin polarization in chiral materials. [ABSTRACT FROM AUTHOR]

The operational stability is a current bottleneck facing the quantum dot light-emitting diodes (QLEDs). In particular, the device working around turn-on voltage suffers from unbalanced charge injection and heavy power loss. Here, we investigate the operational stability of red emissive CdSe QLEDs operated at different applied voltages. Compared to the rising luminance at higher voltages, the device luminance quickly decreases when loaded around the turn-on voltage, but recovers after unloading or slight heat treatment, which is termed fatigue effects of operational QLED. The electroluminescence and photoluminescence spectra before and after a period of operation at low voltages show that the abrupt decrease in device luminance derives from the reduction of quantum yield in quantum dots. Combined with transient photoluminescence and electroluminescence measurements, as well as equivalent circuit model analysis, the electron accumulation in quantum dots mainly accounts for the observed fatigue effects of a QLED during the operation around turn-on voltage. The underlying mechanisms at the low-voltage working regime will be very helpful for the industrialization of QLED. [ABSTRACT FROM AUTHOR]

Quantum dot light-emitting devices (QLEDs) are potential candidates for lighting and display applications. The charge transport mechanism which plays an essential part in the performance of these devices, however, needs to be explored and analyzed for further improvement. The imbalance of the injection and transport of charge carriers within the device adversely affects the efficiency and stability of the device. Charge balance can be improved by better charge injection of holes while suppressing the excessive electrons. A simple and effective strategy to achieve this is using double transport layers or doped transport layers to modulate the band alignment and injection of charge carriers. Here, we propose a new structure and investigate the physical processes within a QLED with a double hole transport layer for improved charge injection of holes and a doped electron transport layer for controlled charge injection of electrons. We find that the process of charge injection, tunneling, and recombination is significantly improved within the quantum dot layer and a better charge balance is achieved in the emissive layer. Through the theoretical simulation model, useful results are obtained which pave the way for designing high-performing QLEDs. [ABSTRACT FROM AUTHOR]

The bismuth vanadate (BiVO4) photoanode receives extensive attention in photoelectrochemical (PEC) water splitting. However, the high charge recombination rate, low electronic conductivity, and sluggish electrode kinetics have inhibited the PEC performance. Increasing the reaction temperature for water oxidation is an effective way to enhance the carrier kinetics of BiVO4. Herein, a polypyrrole (PPy) layer was coated on the BiVO4 film. The PPy layer could harvest the near-infrared light to elevate the temperature of the BiVO4 photoelectrode and further improve charge separation and injection efficiencies. In addition, the conductive polymer PPy layer acted as an effective charge transfer channel to facilitate photogenerated holes moving from BiVO4 to the electrode/electrolyte interface. Therefore, PPy modification led to a significantly improved water oxidation property. After loading the cobalt–phosphate co-catalyst, the photocurrent density reached 3.64 mA cm−2 at 1.23 V vs the reversible hydrogen electrode, corresponding to an incident photon-to-current conversion efficiency of 63% at 430 nm. This work provided an effective strategy for designing a photothermal material assisted photoelectrode for efficient water splitting. [ABSTRACT FROM AUTHOR]

In this work, we design computationally the metal–semiconductor NbS2/BP heterostructure and investigate its atomic structure, electronic properties and contact barrier using first-principles prediction. Our results show that the M–S NbS2/BP heterostructure is energetically stable and is characterized by weak vdW interactions. Interestingly, we find that the combination of the metallic NbS2 and semiconducting BP layers leads to the formation of a M–S contact. The M–S NbS2/BP heterostructure exhibits a p-type Schottky contact and a low tunneling-specific resistivity of 3.98 × 10−10 Ω cm2, indicating that the metallic NbS2 can be considered as an efficient 2D electrical contact to the semiconducting BP layer to design NbS2/BP heterostructure-based electronic devices with high charge injection efficiency. The contact barrier and contact type in the M–S NbS2/BP heterostructure can be adjusted by applying an external electric field. The conversion from p-type ShC to n-type ShC can be achieved by applying a negative electric field, while the transformation from ShC to OhC type can be achieved under the application of a positive electric field. The conversion between p-type and n-type ShC and ShC to OhC type in the NbS2/BP heterostructure demonstrates that it can be considered as a promising material for next-generation electronic devices. [ABSTRACT FROM AUTHOR]

In this study, novel phosphorescent dipyrido[3,2-a;2′3′-c]phenazine (dppz)–platinum(II)–phenylacetylide complexes were developed to fabricate non-doped organic light-emitting diodes (OLED) by solution-processing. To facilitate the charge carrier injection into the emitting layer (EML), 3,6-di-tert-butylcarbazole-functinalized phenylacetylides were employed. As for the dppz ligand, 9,9-dihexylfluoren-2-yl and 4-hexylthiophen-2-yl side-arms were introduced to the 2,7-positions, which led to reddish orange and red photoluminescence (PL), respectively, in solution and film states (PL wavelength: ca. 600 and ca. 625 nm, respectively). The carbazole-appended phenylacetylide ligands hardly affected the emission color, although unsubstituted phenylacetylides gave rise to aggregate- or excimer-based near-infrared PL with a low quantum yield. Two types of non-doped OLEDs were fabricated: single-layer and multilayer devices. In both devices, the organic layers were fabricated by spin-coating, and the EML consisted of a neat film of the corresponding platinum(II) complex. Therein, electroluminescence spectra corresponding to those of PL were observed. The single-layer devices exhibited low device efficiencies due to a deteriorated charge carrier balance. The multilayer devices possessed hole- and electron-transporting layers on the anode and cathode sides of the EML, respectively. Owing to an improved charge carrier balance, the multilayer devices exhibited higher device performance, affording considerably improved values of luminance and external quantum efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] To reveal the mechanism of charge transfer between interfaces of BiVO 4 -based heterogeneous materials in photoelectrochemical water splitting system, the cocatalyst was grown in situ using tannic acid (TA) as a ligand and Fe and Co ions as metal centers (TAFC), and then uniformly and ultra-thinly coated on BiVO 4 to form photoanodes. The results show that the BiVO 4 /TAFC achieves a superior photocurrent density (4.97 mA cm−2 at 1.23 V RHE). The charge separation and charge injection efficiencies were also significantly higher, 82.0 % and 78.9 %, respectively. From XPS, UPS, KPFM, and density functional theory calculations, Ligand-to-metal charge transfer (LMCT) acts as an electron transport highway in TAFC ultrathin layer to promote the concentration of electrons towards metal center, leading to an increase in the work function, which enhances the built-in electric field and further improves the charge transport. This study demonstrated that the LMCT pathway on TA-metal complexes enhances the built-in electric field in BiVO 4 / TAFC to promote charge transport and thus enhance water oxidation, providing a new understanding of the performance improvement mechanism for the surface-modified composite photoanodes. [ABSTRACT FROM AUTHOR]

The hole transport and the carrier distribution in AlGaN-based far-ultraviolett (UVC) light emitting diodes (LEDs) emitting around 233 nm was investigated. Temperature-dependent electroluminescence measurements on dual wavelength AlGaN multiple quantum well (MQW) LEDs show a strong shift in the spectral power distribution from 250 to 233 nm with decreasing temperature. Comparing experimental data with simulation shows that the hole mobility and the electron to hole mobility ratios have a significant influence on the carrier injection efficiency (CIE) and that the change in the spectral power distribution is originating from a change in the hole distribution in the MQWs. Poor hole injection and charge carrier confinement in the AlGaN MQW active region was identified as one of the main reasons for the low CIE in far-UVC LEDs. [ABSTRACT FROM AUTHOR]

Small molecule/polymer semiconductor blends are promising solutions for the development of high‐performing organic electronics. They are able to combine ease in solution processability, thanks to the tunable rheological properties of polymeric inks, with outstanding charge transport properties thanks to high crystalline phases of small molecules. However, because of charge injection issues, so far such good performances are only demonstrated in ad‐hoc device architectures, not suited for high‐frequency applications, where transistor dimensions require downscaling. Here, the successful integration of the most performing blend reported to date, based on 2,7‐dioctyl[1] benzothieno[3,2‐b][1]benzothiophene (C8‐BTBT) and poly(indacenodithiophene‐co‐benzothiadiazole) (C16IDT‐BT), in OFETs characterized by channel and overlap lengths equal to 1.3 and 1.9 µm, respectively, is demonstrated, enabling a transition frequency of 23 MHz at ‐8 V. Two key aspects allowed such result: molecular doping, leading to width‐normalized contact resistance of only 260 Ωcm, allowing to retain an apparent field‐effect mobility as high as 3 cm2/(Vs) in short channel devices, and the implementation of a high capacitance dielectric stack, enabling the reduction of operating voltages below 10 V and the overcoming of self‐heating issues. These results represent a fundamental step for the future development of low‐cost and high‐speed printed electronics for IoT applications. [ABSTRACT FROM AUTHOR]

The performance of electronic and semiconductor devices is critically dependent on the distribution of guest molecules or atoms in a host matrix. One prominent example is that of organic light‐emitting diode (OLED) displays containing phosphorescent emitters, now ubiquitous in handheld devices and high‐end televisions. In such OLEDs the phosphorescent guest [normally an iridium(III)‐based complex] is typically blended into a host matrix, and charge injection and transport, exciton formation and decay, and hence overall device performance are governed by the distribution of the emissive guest in the host. Here high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) is used with depth sectioning to reconstruct the 3D distribution of emissive iridium(III) complexes, fac‐tris(2‐phenylpyridine)iridium(III) [Ir(ppy)3], blended into the amorphous host material, tris(4‐carbazoyl‐9‐ylphenyl)amine (TCTA), by resolving the position of each single iridium(III) ion. It is found that most Ir(ppy)3 complexes are clustered with at least one other, even at low concentrations, and that for films of 20 wt.% Ir(ppy)3 essentially all the complexes are interconnected. The results validate the morphology of blend films created using molecular dynamics simulations which mimic the evaporation film‐forming process and are also consistent with the experimentally measured charge transport and photophysical properties. [ABSTRACT FROM AUTHOR]

Constructing heterostructures from already synthesized two-dimensional materials is of significant importance. We performed a first-principles study to investigate the electronic properties and interfacial characteristics of Janus MoSH/WSi2N4 van der Waals heterostructure (vdWH) contacts. We demonstrate that the p-type Schottky formed by MoSH/WSi2N4 and MoHS/WSi2N4 has extremely low Schottky barrier heights (SBHs). Due to its excellent charge injection efficiency, Janus MoSH may be regarded as an effective metal contact for WSi2N4 semiconductors. Furthermore, the interfacial characteristics and electronic structure of Janus MoSH/WSi2N4 vdWHs can not only reduce/eliminate SBH, but also forms the transition from p-ShC to n-ShC type and from Schottky contact (ShC) to Ohmic contact (OhC) through the layer spacing and electric field. Our results can offer a fresh method for optoelectronic applications based on metal/semiconductor Janus MoSH/WSi2N4 vdW heterostructures, which have strong potential in optoelectronic applications. [ABSTRACT FROM AUTHOR]

Peripheral nerve modulation via electrical stimulation shows promise for treating several diseases, but current approaches lack selectivity, leading to side effects. Exploring selective neuromodulation with commercially available nerve cuffs is impractical due to their high cost and limited spatial resolution. While custom cuffs reported in the literature achieve high spatial resolutions, they require specialized microfabrication equipment and significant effort to produce even a single design. This inability to rapidly and cost-effectively prototype novel cuff designs impedes research into selective neuromodulation therapies in acute studies. To address this, we developed a reproducible method to easily create multi-channel epineural nerve cuffs for selective fascicular neuromodulation. Leveraging commercial flexible printed circuit (FPC) technology, we created cuffs with high spatial resolution (50 μm) and customizable parameters like electrode size, channel count, and cuff diameter. We designed cuffs to accommodate adult mouse or rat sciatic nerves (300–1500 μm diameter). We coated the electrodes with PEDOT:PSS to improve the charge injection capacity. We demonstrated selective neuromodulation in both rats and mice, achieving preferential activation of the tibialis anterior (TA) and lateral gastrocnemius (LG) muscles. Selectivity was confirmed through micro-computed tomography (μCT) and quantified through a selectivity index. These results demonstrate the potential of this fabrication method for enabling selective neuromodulation studies while significantly reducing production time and costs compared to traditional approaches. [ABSTRACT FROM AUTHOR]

The CdSe/CdS/ZnS core/shell/shell quantum dots (QDs) with strong exciton confinement have manifested themselves as competitive light-emitting materials in electrochemiluminescence (ECL). However, cathodic ECL generation by these QDs requires the injection of electron and hole from solid electrode and electrogenerated radicals (for example SO4•−), which is inevitably influenced by not only the inorganic structure of QDs but also the organic ligands on the surface. In this work we aimed at studying the impact of surface organic ligands on ECL performance of CdSe/CdS/ZnS QDs. When changing the surface ligand from oleate to acetate, we phenomenologically observed the positive shift of ECL onset potential by ca. 200 mV and the increase of ECL intensity by ∼ 100 times, suggesting that a short ligand is more favorable for ECL generation. To further comprehend the ligand effect, we measured the charge injection kinetics using potential-modulated, time-resolved photoluminescence, and thin-layer spectroelectrochemistry techniques. The electron and hole injection into QDs were found to be accelerated by 2–20 times if shortening the ligand from oleate to acetate, confirming the significant impact of surface ligands on ECL performance of QDs. The study is expected to provide guidance on how to design surface functionalized QDs for specific applications such as ECL immunodiagnosis, photocatalysis, and photovoltaics. [ABSTRACT FROM AUTHOR]

Multifunctional organic photodetectors (MFOPDs) have garnered significant attention due to their remarkable potential for integrating diverse device functionalities. In contrast to previous MFOPDs that have primarily emphasized the integration of various response bands, a pioneering multifunctional photodetector is introduced based on the P3HT:PC61BM system capable of selectively responding to both wavelength and polarization. Under positive bias, the device operates in a wide‐band, polarization‐insensitive mode, achieving an external quantum efficiency (EQE) of up to 7.01 × 104%. The EQE dichroic ratio (DR) of the device remains <1.01 (at 650 nm). Conversely, under negative bias, the device transitions into a narrow‐band, polarization‐sensitive mode, achieving an EQE of up to 4.82 × 104% with a narrow full width at half maximum (FWHM) of only 25 nm at 650 nm. The EQE DR exceeds 10 in this mode, marking it as one of the highest values within the field of polarization‐sensitive organic photodetectors. This versatile operation is made possible through the strategic use of double‐sided barriers, an oriented light harvesting layer, and a charge injection narrowing (CIN) approach. This work represents a significant advancement toward the realization of multifunctional photodetectors capable of selecting response bands and polarization sensitivity. [ABSTRACT FROM AUTHOR]

Self‐repairing coatings have received widespread attention due to their ability to repair damaged surfaces. However, film‐forming molecules can only be fixed on the metal surface through relatively weak physical and chemical adsorption. This drawback limits its self‐repairing ability. Here, a mode‐switchable TENG (MS‐TENG) is developed, which has the ability to switch between AC and DC outputs as an adjustable charge source for self‐repairing coatings. Besides the normal sector electrodes of rotational TENG, MS‐TENG has a special design of external electrodes (small extension electrodes on rotator and inner/outer orbit electrodes on stator) and achieves charge accumulation through an excitation circuit and DC output through air breakdown on external electrodes with advantage of the complete release of accumulated charges. Compared with traditional air breakdown TENG, its current output has been improved. In addition, the air breakdown process occurs in the external electrode framework independent of the TENG body. Therefore, the negative impact of air breakdown is suppressed. Finally, MS‐TENG is used to achieve rapid electrostatic adsorption of charged film‐forming molecules through charge injection. MS‐TENG as a charge source effectively improves the performance of self‐repairing coatings, with a corrosion inhibition rate of 96.9%. [ABSTRACT FROM AUTHOR]

Ambipolar organic light-emitting transistors (OLETs) are extremely appealing devices for applications from sensing to communication and display realization due to their inherent capability of coupling switching and light-emitting features. However, their limited external quantum efficiency (EQE) and brightness under ambipolar bias conditions hamper the progress of OLET technology. In this context, it was recently demonstrated in multi-stacked devices that the engineering of the interface between the topmost electron-transporting organic semiconductor (e-OS) and the emission layer (EML) is crucial in optimizing the recombination of the minority charges (i.e., electrons) and to enhance EQE and brightness. Here, we introduce a new light-emitting conjugated polar polymer (CPP) in a multi-stacked OLET to improve the electron injection from e-OS to EML and to study, simultaneously, electroluminescence-related processes such as exciton formation and quenching processes. Interestingly, we observed that the highly polar groups present in the conjugate polymer induced polarization-related relevant charge-trapping phenomena with consequent modulation of the entire electrostatic field distribution and unexpected optoelectronic features. In view of the extensive use of CPPs in OLETs, the use of multifunctional CPPs for probing photophysical processes at the functional interfaces in stacked devices may speed up the improvement of the light-emission properties in OLETs. [ABSTRACT FROM AUTHOR]

Metal halide perovskite semiconductors have demonstrated remarkable performance in light‐emitting‐diode applications in recent years. However, their potential application in other emerging optoelectronic devices, such as light‐emitting field‐effect transistors (LEFETs) is impeded by poor luminous efficiency due to inefficient charge injection. Here, an n‐type MgZnInO (MIZO) as the channel layer is synthesized to achieve efficient electron injection in perovskite LEFETs. These findings indicate that the incorporation of Mg not only suppresses the generation of oxygen vacancies but also optimizes the energy level alignment. These synergistic effects reduce non‐radiative recombination and improve interfacial charge transport. Consequently, the MIZO‐based perovskite LEFETs exhibit an improvement in threshold voltage, subthreshold swing, and field‐effect mobility. The electroluminescence performance shows a peak external quantum efficiency (EQE) of 1.97% with a maximum brightness of 2.1 × 104 cd m−2, accompanied by low‐efficiency roll‐off (an EQE of 1.88% at the current density of 810 mA cm−2). To the best of the author's knowledge, this represents the best luminous efficiency reported for perovskite LEFETs to date. [ABSTRACT FROM AUTHOR]