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Due to its extreme susceptibility of tin to oxidation, the power conversion efficiency (PCE) of tin–lead mixed perovskite (TLP) solar cells still lags far behind the pure lead halides perovskite solar cells (PSCs). More than the endeavors of the suppression of tin‐oxidation in the bulk TLP films, the synergistic interface engineering of both grain boundaries and interfaces turns more and more important. Here, a synergistic co‐passivation strategy is reported by modulating poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) substrate with p‐guanidinobenzonitrile hydrochloride (CG) and grain boundary passivation of TLP film with 3‐cyano‐4‐hydrazinylbenzoic acid (3C‐HBA), realizing a competitive device PCE of 23.3%, positioning it at the forefront of reported literature. Strikingly, the discovery of CG modifications for such important PEDOT:PSS layer. Moreover, relying on the comprehensive spectroscopies, 3C‐HBA is revealed to effectively modulate the crystallization process of TLP films. This co‐passivation strategy obviously reduces trap density and suppresses Sn2+ oxidation of TLP devices. [ABSTRACT FROM AUTHOR]

Devices under semi-on-state stress often suffer from more severe current collapse than when they are in the off-state, which causes an increase in dynamic on-resistance. Therefore, characterization of the trap states is necessary. In this study, temperature-dependent transient recovery current analysis determined a trap energy level of 0.08 eV under semi-on-state stress, implying that interface traps are responsible for current collapse. Multi-frequency capacitance–voltage (C-V) testing was performed on the MIS diode, calculating that interface trap density is in the range of 1.37 × 10 13 to 6.07 × 10 12 cm − 2 eV − 1 from E C − E T = 0.29 eV to 0.45 eV. [ABSTRACT FROM AUTHOR]

The presence of hydrogen traps within a metallic alloy influences the rate of hydrogen diffusion. The electro-permeation (EP) test can be used to assess this: the permeation of hydrogen through a thin metallic sheet is measured by suitable control of hydrogen concentration on the front face and by recording the flux of hydrogen that exits the rear face. Additional insight is achieved by the more sophisticated three stage EP test: the concentration of free lattice hydrogen on the front face is set to an initial level, is then dropped to a lower intermediate value and is then restored to the initial level. The flux of hydrogen exiting the rear face is measured in all three stages of the test. In the present study, a transient analysis is performed of hydrogen permeation in a three stage EP test, assuming that lattice diffusion is accompanied by trapping and de-trapping. The sensitivity of the three stage EP response to the depth and density of hydrogen traps is quantified. A significant difference in permeation response can exist between the first and third stages of the EP test when the alloy contains a high number density of deep traps. [ABSTRACT FROM AUTHOR]

The pursuit of near‐ideal subthreshold swing (SS) ≈ 60 mV dec−1 is a primary driving force to realize the power‐efficient field‐effect transistors (FETs). This challenge is particularly pronounced in 2D material‐based FETs, where the presence of a large interface trap density (Dit) imposes limitations on electrostatic control, consequently escalating power consumption. In this study, the gate controllability of 2D FETs is systematically analyzed by fabricating pre‐patterned van der Waals (vdW)‐contacted p‐FETs, varying the WSe2 channel thickness from monolayer to ten‐layer. As a result, the channel thickness is optimized to achieve efficient gate controllability while minimizing Dit. The findings demonstrate negligible hysteresis and excellent subthreshold swing (SSmin) close to the thermal limit (≈60 mV dec−1), with a corresponding Dit of ≈1010 cm−2 eV−1, comparable to Dit values observed in state‐of‐the‐art Si transistors, when utilizing WSe2 channel thicknesses ≥ five‐layer. However, reducing the WSe2 channel thickness below the trilayer, SSmin (≈91 mV dec−1) deviates from the thermal limit, attributed to a comparatively higher Dit (≈1011 cm−2 eV−1), despite the still lower than values reported for surface‐contacted 2D transistors. Furthermore, all devices exhibit consistent p‐type characteristics, featuring a high ION/IOFF ratio, high mobility, and excellent electrical stability confirmed over several months. [ABSTRACT FROM AUTHOR]

Abstract The pursuit of near‐ideal subthreshold swing (SS) ≈ 60 mV dec−1 is a primary driving force to realize the power‐efficient field‐effect transistors (FETs). This challenge is particularly pronounced in 2D material‐based FETs, where the presence of a large interface trap density (Dit) imposes limitations on electrostatic control, consequently escalating power consumption. In this study, the gate controllability of 2D FETs is systematically analyzed by fabricating pre‐patterned van der Waals (vdW)‐contacted p‐FETs, varying the WSe2 channel thickness from monolayer to ten‐layer. As a result, the channel thickness is optimized to achieve efficient gate controllability while minimizing Dit. The findings demonstrate negligible hysteresis and excellent subthreshold swing (SSmin) close to the thermal limit (≈60 mV dec−1), with a corresponding Dit of ≈1010 cm−2 eV−1, comparable to Dit values observed in state‐of‐the‐art Si transistors, when utilizing WSe2 channel thicknesses ≥ five‐layer. However, reducing the WSe2 channel thickness below the trilayer, SSmin (≈91 mV dec−1) deviates from the thermal limit, attributed to a comparatively higher Dit (≈1011 cm−2 eV−1), despite the still lower than values reported for surface‐contacted 2D transistors. Furthermore, all devices exhibit consistent p‐type characteristics, featuring a high ION/IOFF ratio, high mobility, and excellent electrical stability confirmed over several months.

Organic-inorganic methylammonium lead iodide perovskite (MAPbI3) nanowires (NWs) have attracted significant attention in the realm of optoelectronic devices due to their outstanding optoelectronic properties. However, the persistent challenge of high trap densities has been a limiting factor in realizing their full potential in device performance. To address this challenge, we incorporated cesium (Cs) and systematically investigated the impact of Cs concentration on the trap densities and the optoelectronic characteristics of Cs x MA(1− x)PbI3 NWs. Our findings unveiled an initial reduction in trap densities as Cs+ content increased, with the lowest point occurring at x = 0.2. However, beyond this threshold, trap densities began to rise, eventually surpassing those observed in pure MAPbI3 at x = 0.4. Furthermore, we fabricated single NW photodetectors to assess how Cs+ content influenced optoelectronic properties. The results indicated that Cs+ incorporation led to enhancements in photocurrent and response speed, withthe optimal performance observed at x = 0.2. Our study provides valuable insights into the role of Cs+ incorporation in tailoring the optoelectronic properties of perovskite NWs. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiphene):poly(styrene sulfonate) (PEDOT:PSS) is widely used as hole transport layer in photodiodes due to its deep work function, flexibility, low cost, and commercialization potentials. However, organic photodetectors (OPDs) using commercial PEDOT:PSS (C‐PEDOT:PSS) interlayers usually suffer from high noise currents. Here, a simple dilution‐induced strategy is proposed for constructing an ultrathin self‐assembled PEDOD:PSS layer (D‐PEDOT:PSS). Dilution‐induced chain disentanglement leads to smaller grain sizes, which is beneficial to reduce defects and enhances selective charge transport. This enables the fabrication of near‐infrared PM6:Y6 organic photodetectors with three orders of magnitude lower ultra‐low dark current (<1.5×10−10 A cm−2) and one order of magnitude lower spectral‐noise density (2.1×10−14 A Hz−1/2) compared to devices using untreated PEDOT:PSS, at ‐0.1 V applied bias. With low dark current and enhanced responsivity, the shot‐noise‐limited detectivity increases by 35 times. An imaging system using OPDs as a sensing pixel has achieved high‐contrast images, demonstrating the imaging potential of the OPDs. The universality of this strategy to enhance the performance of OPDs is further demonstrated through three additional donor‐acceptor blends. This study presents a simple and effective strategy to reduce the noise current of PEDOT:PSS‐based OPDs and provides insights into the correlation between interfacial properties and the performance of OPDs. [ABSTRACT FROM AUTHOR]

Near‐infrared organic photodetectors (NIR‐OPDs) are of significant applications in optical communication, medical monitoring, and bioimaging, and have become a centerpiece of organic photodetector (OPD) research. To overcome the well‐known challenge of high dark current in NIR‐OPDs, researchers have investigated and introduced the sequential deposition method to prepare photosensitive layers of gradient heterojunction structure. However, this photosensitive layer suffers from the issue of insufficient exciton diffusion length, which in turn limits the photoresponse performance of devices. To address this issue, an interdigital heterojunction (IHJ) structure is designed, forming the adjustable large‐area bicontinuous phase, and constructing rich donor/acceptor interfaces and straightforward carrier transport channels. In this structure, the film shows enhanced crystallinity, which effectively reduces the trap density and suppresses the dark current. In addition, efficient exciton dissociation and charge extraction along with suppressed charge complexation promote the enhanced photoresponse of IHJ devices. Consequently, the IHJ NIR‐OPD achieves a high detectivity of 7.35 × 1013 Jones at 805 nm at −0.2 V, which is one of the highest values at 800–900 nm among reported NIR‐OPDs. Further, the IHJ devices are successfully applied to arterial pulse monitoring and transmission‐based bioimaging. This study provides new insights for realizing high‐performance NIP‐OPDs. [ABSTRACT FROM AUTHOR]

In this paper, an analytical drain current model of double gate MoS2 FET Transistor for low‐frequency noise (LFN) power spectral density is developed, and compared its response with the device simulation of the proposed device structure. The developed low‐frequency noise power spectral density (PSD) model is analyzed with respect to different Trap densities, Oxide thicknesses, and high K‐dielectric materials using the TCAD Device simulation tool. Low‐frequency noise is one of the most important noises in any device since it degrades the device's performance. So, in this paper, we used a unique charge‐control model for analyzing the low‐frequency noise by considering the mobility degradation, trapping, and de‐trapping effects caused by trap densities and device lattice structure. Usually, all the previous studies on drain currents with low frequency are based on fluctuations caused by mobility and carrier variations. In our paper, we even considered the charge density fluctuation to analyze the drain current equation. Using a Charge Control Model, we can compute the parameters like gate capacitance (Cgs, Cgd), channel length modulation, and body effect. While other LFN models like the DC model, small signal model, and hybrid model will focus mainly on the static characteristics of the device such as its DC current–voltage (I‐V) relationship, terminal resistances, and input/output conductance of the devices. All the analytical model results were calibrated with the device simulation and it is observed that both are matches each other. Further, it is observed that with an increase in Trap density, the low‐frequency noise increases and low‐frequency noise is dominant at lower frequencies only (1–10 Hz), and after this frequency range the thermal noise will be the dominant noise factor. [ABSTRACT FROM AUTHOR]

Devices under semi-on-state stress often suffer from more severe current collapse than when they are in the off-state, which causes an increase in dynamic on-resistance. Therefore, characterization of the trap states is necessary. In this study, temperature-dependent transient recovery current analysis determined a trap energy level of 0.08 eV under semi-on-state stress, implying that interface traps are responsible for current collapse. Multi-frequency capacitance–voltage (C-V) testing was performed on the MIS diode, calculating that interface trap density is in the range of 1.37×1013 to 6.07×1012cm−2eV−1 from EC−ET=0.29 eV to 0.45 eV.

Reducing the trap density within organic solar cells is of vital importance to realize high power conversion efficiency (PCE); however, research focusing on this aspect is limited in all‐polymer solar cells (All‐PSCs). In this work, it is found that the trap density can be dramatically reduced by simultaneously obtaining high miscibility of donor and acceptor and ordered packing in blend films through substituting ethylhexyl with hybrid cyclohexyl‐hexyl side chains in the design of the polymer donor. D18‐ChCl with hybrid cyclohexyl‐hexyl chains has a slightly lower aggregation behavior relative to the D18‐Cl counterpart, but reveals synchronously higher miscibility and crystallinity in a blend with the acceptor PYF‐T‐o. Such a morphology evolution positively affects the electronic properties of the device—prolongs the carrier lifetime, facilitates exciton dissociation, and lowers the energy disorder. As a result, the All‐PSC devices based on D18‐ChCl exhibited a remarkable PCE of 17.1%, with a low trap density of 2.65 × 1015 cm−3, a low energy disorder of 47 meV as well as outstanding stability and mechanical durability. This result demonstrates that hybrid cyclohexyl‐hexyl alkyl engineering delicately improves miscibility, drives low trap density, and refines device performance, which brings vibrancy to the All‐PSC research field. [ABSTRACT FROM AUTHOR]

Trap density refers to the density of electronic trap states within dielectric materials that can capture and release charge carriers (electrons or holes) in a semiconductor channel, affecting the transistor's performance. This study aims to investigate the influence of trap density on the electrothermal behavior of nanowire gate-all-around GAAFET devices. The numerical solution of Poisson's equations and continuity equations, coupled with the heat conduction model, has been used to predict the temperature inside the GAAFET device. The finite element method has been used to discretize the semiconductor equations. Investigations have been carried out on a number of physical and geometric parameters, such as oxide thickness, nanowire radius, and gate length. Their effects on output characteristics and device temperature have been discussed. A thinner oxide thickness, lower device radius, and longer channel length led to a higher current flow. Results also reveal that high trap densities can have significant impacts on the degradation of electronic devices, particularly in the context of semiconductor devices like transistors. [ABSTRACT FROM AUTHOR]

High‐performance IR organic photodetectors (OPDs) are of great significance for wireless optical communication, light detection and ranging (LiDAR) technology, and wearable electronics. However, high dark current and low responsivity (R) hinder their future commercial application. Herein, fullerene and non‐fullerene acceptors‐based OPDs are fabricated to understand the relationship between the trap density and photo‐responsivity. Impressively, the non‐fullerene system (Poly([2,6′‐4,8‐di(5‐ethylhexylthienyl)benzo[1,2‐b;3,3‐b]dithiophene]{3‐fluoro‐2[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl}) (PCE10):BTPV‐4F‐eC9) based OPDs exhibits a record R‐value of 0.56 A W−1 at 900 nm in no gain photodiode‐type OPDs, which results in a high detectivity over 1013 Jones in 400–1030 nm at room temperature. Mechanistic studies show that the low trap density plays critical role in reducing the trap‐assisted recombination and density of thermally generated carriers, thus improving the responsivity and reducing the dark current of the device. These findings provide new insights into the mechanism of high‐performance self‐powered near‐infrared OPDs. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional perovskite solar cells (quasi‐2D PSCs) have drawn significant attention and are rapidly developing owing to the impressive stability of the materials and devices. However, there are no reliable guidelines for designing and selecting suitable organic spacer cations to achieve high power conversion efficiency (PCE) in quasi‐2D PSCs. Herein, the effects of the spacer cations with different substituents, i.e., benzylamine (PMA), 4‐methoxybenzylamine (p‐MeOPMA), and 4‐fluorobenzylamine (p‐FPMA), on the optoelectronic properties and device performance of quasi‐2D perovskites are systematically investigated. It is found that the spacer cations with different substituents mainly affect the crystal growth and film quality of quasi‐2D perovskites. Interestingly, quasi‐2D perovskites based on p‐MeOPMA or p‐FPMA exhibit poor crystallinity and crystal orientation, while quasi‐2D perovskite based on the unsubstituted PMA shows improved crystallinity and crystal orientation, which enables suppressed trap densities and efficient charge transport. The PMA‐based quasi‐2D perovskite (nominal n = 3) solar cell exhibits the highest PCE of 13.58%. These results demonstrate that the rational regulation of organic spacer cations plays a crucial role in improving the crystallinity and crystal orientation of perovskite films and elucidate key guiding rules for organic spacer cations for high‐performance quasi‐2D PSCs. [ABSTRACT FROM AUTHOR]

Modern home‐range estimation typically relies on data derived from expensive radio‐ or GPS‐tracking. Although trapping represents a low‐cost alternative to telemetry, evaluation of the performance of home‐range estimators on trap‐derived data is lacking. Using simulated data, we evaluated three variables reflecting the key trade‐offs ecologists face when designing a trapping study: 1) the number of observations obtained per individual, 2) the trap density and 3) the proportion of the home range falling inside the trapping area. We compared the performance of five home‐range estimators (MCP: Minimum Convex Polygon, LoCoH: Local Convex Hull, KDE: Kernel Density Estimation, AKDE: Autocorrelated Kernel Density Estimation, BicubIt: Bicubic Interpolation). We further explored the potential benefits of combining these estimators with asymptotic models, which leverage the saturating behavior of changes in the estimated home‐range area as the number of observations increases to improve accuracy, as well as different data‐ordering procedures. We then quantified the bias in home‐range size under the different scenarios investigated. The number of observations and the proportion of the home range within the trapping grid were the most important predictors of the accuracy and the precision of home‐range estimates. The use of asymptotic models helped to obtain accurate estimates at smaller sample sizes, while distance ordering improved the precision and asymptotic consistency of estimates. While AKDE was the best performing estimator under most conditions evaluated, bicubic interpolation was a viable alternative under common real‐world conditions of low trap density and area covered. A case study using empirical data from white‐tailed deer in Florida and another from jaguars in Belize demonstrated support for the findings of our simulation results. Although researchers with trap data often overlook home‐range estimation, our results indicate that these data have the capacity to yield accurate estimates of home‐range size. Trapping data can, therefore, lower the economic costs of home‐range analysis, potentially enlarging the span of species, researchers and questions studied in ecology and conservation. [ABSTRACT FROM AUTHOR]

The rice stem borer, Chilo suppressalis (Walker) is an oligophagous pest that mainly feeds on rice and currently is largely controlled through chemicals, leading to several ecological problems and often low control efficiency due to the larval feeding habits. Therefore, the alternative and eco-friendly control strategies is needed to manage this noxious insect pests, applications of trapping devices specifically sex pheromone traps are one of the most substitute control methods to monitoring and control moths by killing or mating disruption on large scale. The aim of the current study was to optimize the appropriate pheromone dose, trap density and trap placement height for mating disruption of C. suppressalis. During first year (2021), a mixture of two pheromones (Z11-16: Ald and Z9-16: Ald) in equal ratio (50:50) were applied at different doses (50, 100, 200, 300 and 500µg/20µL), with various trap heights (3, 4.5 and 6 feet) and compared with insecticide (fipronil G 0.2% 15 kg/ha). Results revealed that, 200 and 300µg/20µL caught significantly maximum (119.63±15.86) moths of C. suppressalis and resulted in lowest (4.96%) damage (white ear and dead hearts) as compared to other doses and treatments. The second year's trial was designed to optimize the trap density in which 8, 12, 18 and 25 traps/ha were tested with a median dosage 250µg/20µl, based on first year's results. It exhibited that 18 traps/ha captured maximum number (121.95±19.77) moths and reduced the damage symptoms significantly followed by other 25, 12 and 8 traps/ha with significant difference (P ≤0.001). Moreover, results of best treatment (appropriate sex pheromone dosage, trap placement height and trap density/ha) revealed highest (3:52) cost benefit ratio with minimum (7.90 $) expenditure also highest yield 7400 kg/ha was recorded as compared to other treatments. Therefore, installation of 18 traps/ha at 4.5 feet height with a dose of 250µg/20µL can manage C. suppressalis in rice-growing areas and consequently reduce management cost as compared to the insecticides. Thus, it is recommended as an important component for the eco-friendly management of rice stem borer to ensure food security. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SnO 2 -based ETL layer was enhanced by trap density reduction and making a small energy barrier between ETL and perovskite. • Using sodium trifluoroacetate, the electron mobility of the SnO 2 -based ETL was increased. • The CBM of SnO 2 was modified by reducing the energy barrier of SnO 2 and perovskite films. • By doping sodium trifluoroacetate in the SnO 2 film, the PCE of the perovskite solar cell changed dramatically. Recently, perovskite solar cells have attracted a lot of attention due to their great potential to get high performance and favorable features. One of the most dealt with electron transport layers (ETL) in perovskite solar cells is tin(IV) oxide because of its favorable band alignment in comparison with perovskite active layers' energy band and high charge mobility. Nevertheless, this famous ETL layer has some disadvantages that until now researchers are trying to solve them and the large amount of surface trap density of tin oxide crystals is one of these adverse features. In this research, we offer a new method to enhance the mobility and decrease the surface trape density of the tin oxide crystals ETL by doping sodium trifluoroacetate. By doping sodium trifluoroacetate to ETL Tin oxide-based ETL, the amount of oxygen vacancies in the ETL film shows great decrement and results in enhancement of the electron extraction in the perovskite solar cell. By using doped tin oxide-based ETL in the perovskite solar cell, we were able to achieve 19.51 % of solar cell efficiency with remarkable enhancement in comparison with tin oxide-based ETL without doping. [ABSTRACT FROM AUTHOR]

The corrosive sulfur compounds present in the mineral oil causes the formation of dibenzyl disulfide (DBDS) complex and it can also erode the on-load tap changing selector contacts leading to generation of silver sulfide (AgS2).The present work reports the effect of DBDS and Ag2S concentrations in mineral oil on thermally aged pressboard material. The results demonstrate that surface discharge inception voltage (SDIV) is higher for the aged pressboard specimen. The higher concentrations of DBDS showed a reduction of more than 50% in the magnitude of SDIV compared to its effect with the addition of Ag2S. The surface potential analysis indicates a higher initial potential for the aged specimens with an increased half lifetime. In addition, only deep traps observed on the aged specimens with a slight right shift in its trap energy level. The mechanical strength of aged pressboard specimens with DBDS and Ag2S is understood using tensile testing and simultaneous analysis is captured using Digital Image Correlation (DIC) technique to understand its strain percentage at different areas on the pressboard material during its elongation. The laser induced breakdown spectroscopy (LIBS) analysis is performed to identify the elements responsible for thermal ageing such as carbon, copper and sulfur on the surface of pressboard material. The plasma temperature calculated from sulfur peaks is higher for DBDS aged specimen compared to AgS2 and a linear correlation is observed on the LIBS intensity with ageing duration. Further, the Principal Component Analysis (PCA) is used for its classification on the degradation of pressboard due to the diffusion of both copper and silver sulfide from the mineral oil. The two principal components (PC1 and PC2) provided a higher variance of 99.8% with a clear classification observed between the unaged and aged pressboard specimens due to the addition of both DBDS and Ag2S in mineral oil.

The space charge characteristics of cross-linked polyethylene (XLPE) can be improved to some extent by doping the appropriate amount of nano-MgO. In this study, in order to explore the influence of nano-MgO on the space charge and electric field distributions of the composite insulation of high voltage direct current (HVDC) cable joints, the effect of nano-MgO concentration on the depth and density of the deep traps in MgO/XLPE was first analyzed. On this basis, the charge transport simulation model of a 320 kV HVDC cable joint was established with MgO/XLPE as the cable insulation, and the space charge and electric field distributions of the cable joint under different temperature conditions were simulated. It was found that the radial charge distribution in the joint shows different trends with the change of nano-MgO concentration. There is a significant difference in the charge density on both sides of the (MgO/XLPE)/EPDM interface, and the difference first decreased and then increased with the increase of concentration. When the nano-MgO concentration was 0.5 wt%, the number of charges in the radial direction is the fewest, and the maximum value is only 0.42 C/m−3. The radial electric field changed abruptly at the (MgO/XLPE)/EPDM interface, and it was homogenized to a certain extent with time. It was found that the highest electric field of the interface is at the root of the stress cone, which is the weakest point of the joint insulation. When the nano-MgO concentration was 0.5 wt%, the electric field at the root of the stress cone was found to be the lowest, with a value of 13.38 kV/mm. A comprehensive comparison shows that the joint can maintain better insulation when the concentration is 0.5 wt% compared to other concentrations. The results can provide a basis for further improving the insulation properties of HVDC cable joints through nano doping technology. [ABSTRACT FROM AUTHOR]

We derived a simplified analytical expression to estimate the dynamic reduction in the 2DEG density due to the buffer trapping (${n}_{T}$) in GaN-based high-electron-mobility transistors (HEMTs). To compute ${n}_{T}$ , gate-lag drain current transient (DCT) measurements are carried out at a fixed temperature for different ${V}_{GS}$ points. The dynamic decrease in the 2DEG due to the Fe-related trap at ${E}_{C}$ -0.5 eV is found to be ~ $3.4\times10$ 11 cm−2 in AlGaN/GaN HEMT; thus, ${n}_{T}$ is an essential quantity to evaluate the current collapse effects in HEMT. The validity of the expression is further demonstrated in the C-doped HEMTs. The calculated ${n}_{T}$ for the trap at ${E}_{C}$ -0.14 eV is about $9\times10$ 12 cm−0 in InAlN/GaN HEMT with C-doped buffer, and the calculated ${n}_{T}$ for the trap at ${E}_{C}$ -0.33 eV is ~ $1.2\times10$ 13 cm−2 in AlN/GaN HEMT with C-doped buffer. These values reveal that current collapse effects are more pronounced in the C-doped HEMTs than the Fe-doped HEMTs. Thus, this work is an important first step before further improvements in the model for computing buffer trap concentration. [ABSTRACT FROM AUTHOR]

Summary: The presence of intrinsic defects in the bulk perovskite absorber and recombination of charge carriers hampers the device performance in perovskite solar cells. To overcome the bulk defects in the formamidinium cesium lead iodide (FACsPbI3) perovskite absorber layer, A‐site cation engineering using nitrogen containing heterocyclic aromatic monovalent molecule, glyoxaline iodide/imidazolium iodide (IAI) is carried out successfully in this study. Even though IAI is a relatively larger aromatic cation, an optimized concentration of co‐doping in FACsPbI3 does not destroy the 3D perovskite lattice as evidenced by X‐ray diffraction analysis. Binding energy of Pb‐4f core‐level shifts to lower energy that reveals that the free lone pair of electrons on the nitrogen atom in IAI binds with the undercoordinated Pb2+, which results in in situ defect passivation. As a result, the in situ passivated device shows reduced trap filled limit voltage (VTFL) of 0.09 V (from 0.19), lower trap state density (~1.05 × 1015 cm−3), and reduced diode ideality factor (nid) of 1.36 from 1.48. Due to the reduced nonradiative recombination an increased trap‐assisted lifetime of 410 ns was also observed compared to the bare device (177 ns). The lower theoretical open circuit voltage (VOC) loss with enhanced theoretical fill factor (FF0) reveals that the incorporation of third A‐site cation results in reduced charge carrier transport loss. Finally, the in situ passivated device shows 60 mV higher open‐circuit voltage (VOC) than the bare device (1.01‐1.07 V) with enhanced fill factor, which leads to an improved power conversion efficiency of 16.02%. The findings reported here demonstrate the beneficial role of the third A‐site cation in passivating the inherent defects seen in formamidinium cesium lead iodide absorber. [ABSTRACT FROM AUTHOR]

The efficiency of perovskite photovoltaics remains distant from their theoretical limits, primarily due to high photovoltage losses. Here a strategy is reported to minimize voltage losses by reconstructing the perovskite surface into a bilayer heterojunction (BLH) structure. Unlike conventional low-dimensional capping layers, typically constrained to a few nanometers to prevent low fill factors, this methodology facilitates a more comprehensive reaction with surface defects, allowing a more substantial capping layer (≈50 nanometers) without compromising charge transport integrity. Time-resolved microwave conductivity analysis indicates a significant reduction in trap density at the top region of the perovskite film, showing an order of magnitude lower than that of the pristine sample. Incorporating this BLH in inverted cells results in a remarkably low photovoltage deficit of 325 mV, leading to a power conversion efficiency (PCE) of 26.1% (25.72% certified). The encapsulated device maintains 94% of its original efficiency after 1200 h of maximum power point tracking under one sun illumination at 65 °C., (© 2024 Wiley‐VCH GmbH.)

A smelting multiple recrystallization strategy and its effects on the morphology, composition, and defects of CsPbBrI2 film were investigated. An optimal number (n = 2) of recrystallization cycles improved the crystallinity and phase purity, minimized the grain boundaries, and optimized the crystal structure, yielding a high-quality perovskite film with significantly reduced defects density. The corresponding photovoltaic devices exhibited a champion efficiency of 16.02% under AM 1.5 G illumination and presented an even higher indoor efficiency of 33.50% under an LED (2956 K, Pin: 334.41 μW/cm2). This recrystallization method offers a promising strategy for developing high-performance indoor and outdoor photovoltaics. Direct recrystallization in the cells was also explored to achieve enhanced stability and longer lifetime in humid conditions.

The metal oxides with low trap density of states as the electron transport layer are crucial for the high performance of the organic solar cells (OSCs). It is universally acknowledged that modifying n-type metal oxide contacts with polymer donors will harm the carrier extraction on account of the mismatched energy level. However, we find that modifying interlayer consisting of the alcohol amines with some polymer donor additive can unusually enhance the performance of the OSCs. Compared with triethanolamine (TEA) passivated ZnO, TEA:polymer donor treated ZnO shows lower trap density and enhances electron mobility resulting in higher current density in OSC devices. Here, we reveal that the enhanced oxygen-defect passivation ability of TEA with polymer additive is attributed to the enhanced negative electrostatic potential of TEA owing to the hydrogen bond formation between the polymer and the hydroxyl group in TEA. This strategy that enhancing the negative electrostatic potential of the passivators for improving oxygen defect passivation can be extended to other types of organic electronic devices. [ABSTRACT FROM AUTHOR]

Enhancement-mode 4H-SiC MOSFETs utilising an aluminium oxide (Al 2 O 3 ) dielectric without the requirement for an underlying silicon oxide (SiO 2 ) layer have been shown to have a field effect mobility of 150 cm 2 V − 1 s − 1 and a subthreshold swing of 160 mV/dec. The fabricated devices utilised a forming gas (3% H 2 in N 2 ) anneal immediately prior to the deposition of the Al 2 O 3 by Atomic Layer Deposition (ALD). A comparison MOSFET using an identical Al 2 O 3 deposition process with a 0.7 nm SiO 2 layer had a field effect mobility of approximately 20 cm 2 V − 1 s − 1 . The hydrogen annealed device had a lower density of interface traps ( D it ), a lower subthreshold swing, and a significantly reduced hysteresis in the transconductance data than the thin SiO 2 sample. This finding solves the issue of inconsistency of device performance using thin film gate dielectric as an interfacial layer by offering a simple and controllable process. [ABSTRACT FROM AUTHOR]

Polymer materials with excellent physicochemical and electrical properties are desirable for energy storage applications in advanced electronics and power systems. Here, Al2O3@ZrO2 nanoparticles (A@Z) with a core-shell structure are synthesized and introduced to a P(VDF-HFP) matrix to fabricate P(VDF-HFP)/A@Z nanocomposite films. Experimental and simulation results confirm that A@Z nanoparticles increase the crystallinity and crystallization temperature owing to the effect of the refined crystal size. The incorporation of A@Z nanoparticles leads to conformational changes of molecular chains of P(VDF-HFP), which influences the dielectric relaxation and trap parameters of the nanocomposites. The calculated total trapped charges increase from 13.63 μC of the neat P(VDF-HFP) to 47.55 μC of P(VDF-HFP)/5 vol%-A@Z nanocomposite, indicating a substantial improvement in trap density. The modulated crystalline characteristic and interfaces between nanoparticles and polymer matrix are effective in inhibiting charge motion and impeding the electric conduction channels, which contributes to an improved electrical property and energy density of the nanocomposites. Specifically, a ~200% and ~31% enhancement in discharged energy density and breakdown strength are achieved in the P(VDF-HFP)/5 vol%-A@Z nanocomposite. [ABSTRACT FROM AUTHOR]

A new Double-BOX structure is introduced to explore the electrical properties of the trap-rich layer used to enhance the performance of radio frequency Silicon-on-Insulator substrates. Capacitance-voltage (C-V) measurements reveal anomalous behavior with a "shoulder" emerging in the electron accumulation region and a shift towards negative gate voltage in hysteresis. TCAD simulation shows that these features are related to trap states at the grain boundary in the trap-rich polycrystalline silicon (polysilicon) layer. These traps form a potential barrier and affect the C-V curves. To determine the traps density in polysilicon, a three-element circuit model is used. The effective density of fast traps is evaluated from the corrected C-V curve, while the hysteresis of double-sweep C-V measurement yields the slow traps density at the grain boundary in polysilicon. [ABSTRACT FROM AUTHOR]

[Display omitted] • Structural and morphological characterization of Pulsed Laser deposited BiFeO 3 films at different deposition temperature. • Chemical state analysis along with absorption and emission studies of films. • Modulation of defect type and density with deposition temperature. • Estimation of defect levels, carrier type and defect densities. This research investigates the structural, topological, electrical and optical properties of pulsed laser deposited polycrystalline BiFeO 3 thin films on silicon and glass substrate at varying deposition temperatures ranging from 400 °C to 700 °C. X-ray diffraction confirm rhombohedral phase and X-ray photoelectron spectroscopy reveals stoichiometric BiFeO 3 films. The optical bandgap of thin films obtained from absorption spectra increases with the substrate temperature. Photoluminescence emission spectrum reveals the defects and Atomic Force Microscopy analysis bring out the surface topography and crystallinity improvement with temperature. The charge transport studies reveal a transition in conductivity from n-type at lower deposition temperature to p-type at higher deposition temperature, attributed to oxygen and bismuth vacancies respectively. The intricate understanding of conductivity tuning and the leaky nature of BiFeO 3 thin film opens avenues for applications in non-volatile memories, particularly neuromorphic devices. [ABSTRACT FROM AUTHOR]

• New Double-BOX structure used to characterize trap density in trap-rich layer. • Characterize the trap density by capacitance–voltage method. • Potential barrier at the grain boundary causes the anomalous behavior. • Use a three-element circuit model with tangential approximation method for correction. • Provide a simple method for characterization at wafer level. A new Double-BOX structure is introduced to reveal the electrical properties of undoped polysilicon used to enhance the performance of radio frequency SOI substrates. A plateau is clearly observed in the capacitance–voltage (C-V) characteristics, which is due to the influence of the potential barrier formed at the grain boundary. A tangential approximation method based on a three-element circuit model is proposed for correcting the measured C-V curve. With the corrected C-V curve, the effective trap density distribution in polysilicon is determined for each frequency. [ABSTRACT FROM AUTHOR]

[Display omitted] The performance of perovskite solar cells (PSCs) can be improved by optimizing the perovskite film quality and electron transfer layers (ETLs). In this study, high-efficient PSCs with multi-cation hybrid electron transport layer (SnO 2 @Na:Cs ETL) were fabricated using continuous spin-coating. Compared to the pristine SnO 2 , the power conversion efficiency (PCE) of device based on SnO 2 @Na:Cs ETL have reached 22.06% (with an open circuit voltage of 1.13 V), up approximately 21%. The photovoltaic performance of the device is enhanced due to the increase in the transmission rate, electrical conductivity, electron mobility and surface state owing to the multi-cation hybrid. In addition, because SnO 2 @Na:Cs ETL can significantly improve interface contact with the perovskite film and improve its crystallinity, the transport defect state and carrier transport efficiency are significantly improved at the ETL/Perovskite interface. Therefore, the open circuit voltage (V oc) and fill factor (FF) of PSCs was significantly increased. The application of SnO 2 @Na:Cs ETL provides a simple and efficient method to obtain highly-efficient PSCs. [ABSTRACT FROM AUTHOR]

The past decade has witnessed tremendous advancement in the field of halide perovskite (PSK) as a choice of material for high‐performing solar cells fabrication. Here, we investigate the impact of the halide exchange through N‐bromosuccinimide (NBS) treatment in MAPbI3 based solar cells. We observed the partial halide exchange (I− to Br−) or the filling of halide (X−) vacancy upon treatment of different NBS concentrations experimentally by spectroscopic and diffractogram studies. We noted that halide exchange impacts the crystallization and is beneficial in improving the photovoltaic performance. The optimized 0.5 % NBS treated PSC exhibited a power conversion efficiency of 17.87 % due to an increment in open‐circuit voltage (Voc) and short circuit current (Jsc). We noted improved perovskite crystal growth upon Br− substitution; eventually, it helps to lower the trap density, reducing non‐radiative recombination and renders the enhancement of long‐term stability of PSC. [ABSTRACT FROM AUTHOR]

The date palm fruit stalk borer, Oryctes elegans Prell (Coleoptera: Scarabaeidae), is one of the most destructive endemic pests of palm groves in Iran. Recently, there has been a trend toward using kairomone or pheromone trapping as a preferred method of controlling this borer to preserve and protect the environment. The current field study examined the effects of trap density (6 or 10 traps/ha) and trap color (black, white, red, and yellow) on the attraction of adults of O. elegans to a Kairo-pheromonal diffuser (Ferrolure manufactured by Econex Ltd, Spain) in four infested date palm groves in Shalheh-ye Emam Hasan, Abadan, southwestern Iran. Among the test density, 6 traps/ha could accurately detect the presence of adults of O. elegans in the field and help monitor O. elegans. However, 10 traps/ha caught significantly more adults than 6 traps/ha. At both densities, trap colors significantly affected adults' mobility and dispersal to traps. The black traps captured the most significant number of adults in the field, followed by the yellow, red, and white traps. In addition, there was no significant difference between the total numbers of adults captured in traps with different colors during four different times of sampling. As a result, the black traps with 10 traps/ha yield better results at capturing in the field. Our results provide the basic information for developing a safe mass trapping system to control O. elegans. [ABSTRACT FROM AUTHOR]

Typical organic semiconductors show a high trap density of states (1016–1018 cm−3), providing a large number of centers for charge‐carrier recombination, thus hindering the development of photocatalytic hydrogen evolution. Here, we design and synthesize a two‐dimensional polycyclic photovoltaic material, named as TPP, to reduce the trap density to as low as 2.3×1015 cm−3, which is 1–3 orders of magnitude lower than those of typical organic semiconductors. Moreover, TPP exhibits a broad and strong absorption, ordered molecular packing with a large crystalline coherence length and enhanced electron mobility. Then, the bulk heterojunction nanoparticles (BHJ‐NPs) based on a blend of polymer donor (PM6) and TPP exhibit an average hydrogen evolution rate (HER) of 64.31 mmol h−1 g−1 under AM1.5G sunlight (100 mW cm−2), and 72.75 mmol h−1 g−1 under 330–1100 nm illumination (198 mW cm−2) higher than that of the control NPs based on typical PM6 : Y6 (62.67 mmol h−1 g−1). [ABSTRACT FROM AUTHOR]

Simple Summary: Drosophila suzukii is an invasive fruit fly that have became a key pest of soft-skinned fruits during the past decade. Today, the control of this pest relies strongly on broad-spectrum insecticides. Deploying attractive traps to control the pest population (mass trapping) could be part of the management strategy of D. suzukii. The present study analyses whether mass trapping with different attractants could be viable for D. suzukii control and how far traps should be maximally spaced in a grid. Traps in a grid compete for the same insects when they are spaced close enough and their radii of attraction overlap. Since the traps on the corners of a grid have fewer competing traps around than fully surrounded centre traps, the ratio of the catches in the corner traps and the centre traps indicates whether the traps are spaced close enough. By quantifying that trap interference in 4 × 4 trapping grids, it was found in this two-year field study that workable trap densities can be expected to control D. suzukii. From June onwards, synthetic lures in dry traps show equal or better results than the same traps with a reference liquid bait (apple cider vinegar). The invasion of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) worldwide has disrupted existing or developing integrated pest management (IPM) programs in soft-skinned fruits. Currently, with a reliance on only broad-spectrum insecticides, there is a critical call for alternative control measures. Behavioural control is one of the pillars of IPM, and, in the present study, it is investigated whether mass trapping could be viable for D. suzukii management. By quantifying trap interference in 4 × 4 replicate trapping grids, an estimate of the attraction radius for a certain attractant and context can be obtained. Traps designed for dry trapping (no drowning solution, but a killing agent inside) and synthetic controlled released experimental lures were tested in a two-year field study. Apple cider vinegar (ACV) was included as a reference bait and trials were performed with 5, 10 and 15 m inter-trap spacings at different seasonal timings. Clear trap interference and, hence, overlapping attraction radii were observed both in spring and summer for both the synthetic lures and ACV. In early spring, ACV shows the most potential for mass trapping, however from June onwards, the experimental dry lures show equal or better results than ACV. Based on our findings, workable trap densities are deemed possible, encouraging further development of mass trapping strategies for the control of D. suzukii. [ABSTRACT FROM AUTHOR]

We demonstrated that channel mobility and cell current could be increased through Ge diffusion engineering and H2 plasma treatment in a poly-Si channel. Even though the Ge channel has a higher intrinsic mobility than the Si channel, a typical poly-SiGe channel has inferior channel characteristics due to high interface trap density (Dit) and bulk trap density caused by Ge. We propose a novel technique to control the Ge profile along the depth direction of the channel to realize lower Ge concentration at the gate dielectric interface and higher Ge concentration at the channel bulk. This Ge profile could achieve reduced Dit and enhanced channel mobility. Furthermore, the bulk traps caused by Ge are effectively reduced by H2 plasma treatment. These techniques increased the channel mobility to 32%, which can help increase the channel mobility of devices where poly-Si channels are used. [ABSTRACT FROM AUTHOR]

Integrated perovskite/organic solar cells (IPOSCs) have shown great potential in broadening the light absorption range and improving the photovoltaic performance. However, the severe interface charge recombination and unmatched energy levels between perovskite and organic photoactive layers hinder their performance improvement. Here, an efficient interface passivation strategy for IPOSCs based on a layered Ruddlesden–Popper (RP) perovskite and high photovoltaic performance is successfully demonstrated. It is found that an ultrathin conjugated polymer (PM6) layer could passivate the surface defects of perovskite film, tuning the energy level and suppress the nonradiative recombination loss, leading to efficient interface contact between RP perovskite and organic photoactive layers, boosting the open‐circuit voltage from 1.06 to 1.12 V and the efficiency from 17.23% to 19.15%. Importantly, the optimized device shows extended photocurrent response to 930 nm with a peak intensity close to 50% from 800 to 931 nm. The results indicate that interface passivation using a functionalized polymer could be an efficient strategy to improve the photovoltaic performance of integrated devices. [ABSTRACT FROM AUTHOR]

We report a high-performance transparent amorphous indium gallium zinc oxide thin-film transistor (a-IGZO TFT) gated by atomic layer deposition (ALD)-deposited HfAlOx. Through a postfabrication annealing optimization process, the total trap density of the device can be reduced in two orders of magnitudes. The subthreshold swing (SS) reaches an ultralow level of 62.29 mV/dec due to the low defect states. A large $I_{\text{ON}}/I_{\text{OFF}}$ and a high mobility of 2.76 $\times 10^{{9}}$ and 18.94 cm2/ $\text{V}\cdot \text{s}$ can be achieved, respectively. In addition, the devices exhibit good stability in terms of positive bias stress, thermal, and aging tests. The defect optimization process has been verified by the X-ray photoelectron spectroscopy analysis. Finally, a resistor-loaded inverter was constructed, which showed ideal swing characteristics and its voltage gain was as high as 39 at 7 V. These results indicate such a-IGZO TFT is of great potential for the emerging electronics, large-area display, and other low-power electronics. [ABSTRACT FROM AUTHOR]

Dielectric response and charge decay test are widely used for evaluating the electric properties of the insulation pressboards in the converter transformer. In this paper, Frequency Domain Spectroscopy (FDS) test, breakdown test, and charge decay characteristics experiments are carried out on the cellulose pressboards modified by TiO 2 with different mass fractions and diameters. The FDS of the modified cellulose pressboards at ambient temperature is measured from 0.0001 to 1000 Hz by IDAX 300. The process is conducted at the laboratory to study the characteristics parameters of the dielectric response behaviors, such as complex relative permittivity. The results show that the values of the relative permittivity for the insulation pressboards modified by TiO 2 (5 wt%, 10 nm) are reduced. To verify the accurate results, the microstructures of the pressboards modified by 5 wt% with 10 nm diameter are observed by a Scanning Electron Microscope (SEM). The breakdown strength tests are carried on the samples modified by 1 wt%, 3 wt%, 5 wt%, 7 wt% with 10 nm TiO 2 under the intensity electric and high-temperature field, respectively. The values of the breakdown strength are increased by 38% and 11.5% for single layer samples and oil/pressboard composite insulation models modified by 5 wt% nano-TiO 2 filler. In addition, the charge decay characteristics are tested on the samples. The proper proportion additions can reduce the trap density. [ABSTRACT FROM AUTHOR]

The space charge characteristics of cross-linked polyethylene (XLPE) can be improved to some extent by doping the appropriate amount of nano-MgO. In this study, in order to explore the influence of nano-MgO on the space charge and electric field distributions of the composite insulation of high voltage direct current (HVDC) cable joints, the effect of nano-MgO concentration on the depth and density of the deep traps in MgO/XLPE was first analyzed. On this basis, the charge transport simulation model of a 320 kV HVDC cable joint was established with MgO/XLPE as the cable insulation, and the space charge and electric field distributions of the cable joint under different temperature conditions were simulated. It was found that the radial charge distribution in the joint shows different trends with the change of nano-MgO concentration. There is a significant difference in the charge density on both sides of the (MgO/XLPE)/EPDM interface, and the difference first decreased and then increased with the increase of concentration. When the nano-MgO concentration was 0.5 wt%, the number of charges in the radial direction is the fewest, and the maximum value is only 0.42 C/m−3. The radial electric field changed abruptly at the (MgO/XLPE)/EPDM interface, and it was homogenized to a certain extent with time. It was found that the highest electric field of the interface is at the root of the stress cone, which is the weakest point of the joint insulation. When the nano-MgO concentration was 0.5 wt%, the electric field at the root of the stress cone was found to be the lowest, with a value of 13.38 kV/mm. A comprehensive comparison shows that the joint can maintain better insulation when the concentration is 0.5 wt% compared to other concentrations. The results can provide a basis for further improving the insulation properties of HVDC cable joints through nano doping technology.

A double-carrier organic light-emitting device consisting of tris(8-hydroxyquinoline) aluminum (III) (Alq3) as the emissive layer (OLED A) is fabricated. The trap density value obtained at voltage of 14 V when the device luminesces is 2.40 × 1015 cm−3. The rates of the capturing process (trapping) Rn and de-trapping, R n ′ of the charge carriers on the localized state of the double-carrier device are estimated. There are two significant regions observed in the plot, Rn > R n ′ and Rn < R n ′ , and the intersection point of Rn with that of R n ′ indicates the voltage at which the device luminesces, known as the turn-on voltage of the device. Simulations are then performed by directly increasing the device trap density by various ratios to that of OLED A. The simulation has indicated that trap density has a strong influence on the Rn and R n ′ parameters. In order to verify the finding of the simulation, another double-carrier device (OLED B) with a hole transport layer (HTL) of poly(N,N′-bis-4 butyl phenyl-N,N′-bisphenyl) benzidine (poly-TPD) of 40-nm thickness is fabricated by adding the HTL layer to the existing structure of OLED A. The photoelectric characteristics analysis is performed on both types of OLED A and B. In this work, OLED B proved to have a higher value of trap density luminescence at a much lower turn-on voltage, as has been predicted by the simulation results due to the influence of trap density on the parameters Rn and R n ′ of the devices. [ABSTRACT FROM AUTHOR]

Low-frequency noise characteristics of ZnO nanowire field-effect transistors (FETs) are presented at temperatures down to 10 K. The carrier number fluctuation (CNF) model and Hooge’s model are used to analyze the low-frequency noise in the studied devices. From 293 down to 200 K, the normalized noise power spectrum density (PSD) is proportional to (gm/Id)2 due to CNF caused by the trapping and detrapping process between the channel carriers and oxide traps near the semiconductor and the dielectrics interface. In this case, the low-frequency noise is induced by flat-band voltage fluctuation. The density of the traps in the gate dielectrics near the Fermi level ranges from 9.4 × 1010 to 3.8 × 1010 cm−2 eV−1 from 293 and 200 K. At lower temperatures, from 150 down to 100 K, the noise mechanism is mobility fluctuation, attributed to electron and space-charge scattering due to the hoping process and slow motions of electrons. The extracted Hooge’s parameter in this temperature ranges in the order of 10−3 to 10−2. In the temperature range from 30 down to 10 K, the low-frequency noise is dominated by both CNF and mobility fluctuation caused by Coulomb scattering between oxide traps and electrons. [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenides (TMDs) are promising semiconductive films for applications in future devices due to their prosperous and tunable band structures. However, most TMD‐based top gate transistors suffer from a significant doping effect in the channel due to the subsequent deposition high‐k dielectric layer and metal gate, which limits their practical applications. In this work, the channel doping effect caused by various processing steps based on mechanical exfoliated MoS2 sheets is systematically investigated. This work illustrates a clear correlation among these steps and provides a simple and efficient methodology to realize high‐performance enhancement mode MoS2 field effect transistors, which can be extended to other 2D materials. [ABSTRACT FROM AUTHOR]

Polymer/organic solar cells (PSCs) are one promising candidate for sustainable technologies of converting solar energy to electricity, making impressive progress with the power conversion efficiencies of single-junction devices exceeding 18–19%. The trap density of states (tDOS) of polymer/organic semiconductors ranging from 1016∼1018 cm−3 are much higher than those traditional inorganic/hybrid semiconductors, thus PSCs continue to face a remaining challenge to achieve close efficiency levels as approaching Shockley-Queisser limit or their inorganic counterparts, such as single-crystal silicon solar cells. Hence, comprehending the sources and distributions of tDOS in PSCs is of utmost importance to implement appropriate approaches to mitigate the defects in devices. Here we summary the understanding of defect origins in PSCs and elucidate the techniques employed for evaluating the spatial and energetic distribution of tDOS and offer a perspective and outlook in the field of PSCs from the view of trap suppression. • The trap density of states (tDOS) of typical polymer/organic semiconductors ranging from 1016∼1018 cm−3 are much higher than those inorganic/hybrid semiconductors, thus polymer/organic solar cells (PSCs) face a challenge to rival inorganic device efficiency. • Comprehending the sources and distributions of tDOS in PSCs is of utmost importance to implement appropriate approaches to mitigate the defects in devices. • We summary the understanding of defect origin in PSCs and elucidate the techniques employed for evaluating the spatial and energetic distribution of tDOS and offer a perspective and outlook in the field of PSCs from the view of trap suppression. [ABSTRACT FROM AUTHOR]

Enhancement-mode 4H-SiC MOSFETs utilising an aluminium oxide (Al2O3) dielectric without the requirement for an underlying silicon oxide (SiO2) layer have been shown to have a field effect mobility of 150 cm2V−1s−1 and a subthreshold swing of 160 mV/dec. The fabricated devices utilised a forming gas (3% H2 in N2) anneal immediately prior to the deposition of the Al2O3 by Atomic Layer Deposition (ALD). A comparison MOSFET using an identical Al2O3 deposition process with a 0.7 nm SiO2 layer had a field effect mobility of approximately 20 cm2V−1s−1. The hydrogen annealed device had a lower density of interface traps (Dit), a lower subthreshold swing, and a significantly reduced hysteresis in the transconductance data than the thin SiO2 sample. This finding solves the issue of inconsistency of device performance using thin film gate dielectric as an interfacial layer by offering a simple and controllable process.

Polymer materials with excellent physicochemical and electrical properties are desirable for energy storage applications in advanced electronics and power systems. Here, Al2O3@ZrO2 nanoparticles (A@Z) with a core-shell structure are synthesized and introduced to a P(VDF-HFP) matrix to fabricate P(VDF-HFP)/A@Z nanocomposite films. Experimental and simulation results confirm that A@Z nanoparticles increase the crystallinity and crystallization temperature owing to the effect of the refined crystal size. The incorporation of A@Z nanoparticles leads to conformational changes of molecular chains of P(VDF-HFP), which influences the dielectric relaxation and trap parameters of the nanocomposites. The calculated total trapped charges increase from 13.63 μC of the neat P(VDF-HFP) to 47.55 μC of P(VDF-HFP)/5 vol%-A@Z nanocomposite, indicating a substantial improvement in trap density. The modulated crystalline characteristic and interfaces between nanoparticles and polymer matrix are effective in inhibiting charge motion and impeding the electric conduction channels, which contributes to an improved electrical property and energy density of the nanocomposites. Specifically, a ~200% and ~31% enhancement in discharged energy density and breakdown strength are achieved in the P(VDF-HFP)/5 vol%-A@Z nanocomposite.

Additive engineering is one of the most efficient approaches to improve not only photovoltaic performance but also phase stability of formamidinium (FA)‐based perovskite. Chlorine‐based additives, such as methylammonium chloride (MACl), have been in general used to improve phase stability of FAPbI3, which however often leads to loss of open‐circuit voltage Voc, accompanied by instability of the perovskite phase due to the volatile nature of the MA cation. A dual additive strategy for improving Voc and thereby the overall efficiency are reported here. The mixing ratio of MACl to CsCl is varied from [MACl]/[CsCl] = 4 to 1, where Voc increases with decreasing the ratio and best performance is achieved from [MACl]/[CsCl] = 2. As compared to the single source of MACl, the addition of CsCl reduces trap density and increases resistance against charge recombination, which is responsible for the increased Voc. Moreover, defect passivation achieved by dual additive enables better stability than the single additive MACl as confirmed by long‐term stability tests with unencapsulated devices for 50 days under relative humidity of about 40% at room temperature. The best power conversion efficiency of 23.22% is achieved by dual additive, which is higher than that for single additive of MACl or CsCl. [ABSTRACT FROM AUTHOR]