Optoelectronic Characteristics Research Articles

Mechanisms of Phase Evolution in the Cu-Sb-S System Controlled by the Incorporation of Cu in Sb2S3 Thin Films.

Ongoing research in metal chalcogenide semiconductors aims to develop alternative materials for optoelectronic devices. However, due to cost and environmental considerations, there is an increasing emphasis on utilizing green materials. This shift toward sustainable materials and processing is expected to become essential in materials research. In this work, we report the microstructural evolution of thin films of the Cu-Sb-S (CAS) system. The films were obtained by annealing amorphous Sb2S3 precursor films previously immersed in a copper solution with variable residence time. Our main findings demonstrate that varying the residence time in immersion together with the annealing and crystallization of the precursor films leads to a controlled incorporation/distribution of Cu into the films, which promotes the formation of films with phases spanning from a mixture between Sb2S3 and CuSbS2 to a pure Cu12Sb4S13 phase, which represents a significant variation in optoelectronic properties. The phase transition mechanisms were investigated using first-principles calculations and correlated with the structural, morphological, and optoelectronic characterization. Results indicate that vacancies serve as nucleation sites for copper incorporation. Subsequently, interstitial sites are occupied during the phase transformation from Sb2S3 to CuSbS2, whereas the transition from CuSbS2 to Cu12Sb4S13 proceeds via a substitutional mechanism. This study contributes to understanding the fundamental phenomena underlying our proposed methodology. These results could promote the development of CAS-based semiconductors with predetermined properties by manipulating simple process parameters, such as the residence time in a copper solution.

Wide-Bandgap Lead Halide Perovskites for Next-Generation Optoelectronics: Current Status and Future Prospects.

Over the past decade, lead halide perovskites (LHPs), an emerging class of organic-inorganic ionic-type semiconductors, have drawn worldwide attention, which injects vitality into next-generation optoelectronics. Facilely tunable bandgap is one of the fascinating features of LHPs, enabling them to be widely used in various nano/microscale applications. Notably, wide-bandgap (WBG) LHPs have been considered as promising alternatives to traditional WBG semiconductors owing to the merits of low-cost, solution processability, superior optoelectronic characteristics, and flexibility, which could improve the cost-effectiveness and expand the application scenarios of traditional WBG devices. Herein, we provide a comprehensive review on the up-to-date research progress of WBG LHPs and their optoelectronics in terms of material fundamentals, optoelectronic devices, and their practical applications. First, the features and shortcomings of WBG LHPs are introduced to objectively display their natural features. Then we separately depict three typical optoelectronic devices based on WBG LHPs, including solar cells, light emitting diodes, and photodetectors. Sequentially, the inspiring applications of these optoelectronic devices in integrated functional systems are elaborately demonstrated. At last, the remaining challenges and future promise of WBG LHPs in optoelectronic applications are discussed. This review highlights the significance of WGB LHPs for promoting the development of the next-generation optoelectronics industry.

High-Performance Green and Blue Light-Emitting Diodes Enabled by CdZnSe/ZnS Core/Shell Colloidal Quantum Wells.

The unique anisotropic properties of colloidal quantum wells (CQWs) make them highly promising as components in nanocrystal-based devices. However, the limited performance of green and blue light-emitting diodes (LEDs) based on CQWs has impeded their practical applications. In this study, alloy CdZnSe core CQWs with precise compositions are tailored via direct cation exchange (CE) from CdSe CQWs with specific size, shape, and crystal structure and utilized hot-injection shell (HIS) growth to synthesize CdZnSe/ZnS core/shell CQWs exhibiting exceptional optoelectronic characteristics. This approach enabled the successful fabrication green and blue LEDs manifesting superior performance compared to previously reported solution-processed CQW-LEDs. The devices demonstrated a remarkable peak external quantum efficiency (20.4% for green and 10.6% for blue), accompanied by a maximum brightness 347,683cd m-2 for green and 38,063cd m-2 for blue. The high-performance represents a significant advancement for nanocrystal-based light-emitting diodes (Nc-LEDs) incorporating anisotropic nanocrystals. This work provides a comprehensive synthesis strategy for enhancing the efficiency of Nc-LEDs utilizing anisotropic nanocrystals.

Simulation and optimization of strained GeSn laser with SiN-induced stress

By modifying Germanium (Ge) material, direct bandgap emission can be achieved, improving light emission efficiency. This paper proposes a strain-engineered GeSn laser based on SiN stress. The stress distribution within the device and its optoelectronic characteristics were analyzed through simulation. The laser is predicted to emit light at a wavelength of approximately 2252 nm, with a threshold current density around 220 kA/cm2. By introducing a multi-quantum well (MQW) structure, the threshold current density is reduced to about 90 kA/cm2. The work in this paper provides a feasible technical solution for the design of efficient silicon-based light sources.

Visible-Light-Stimulated Optoelectronic Neuromorphic Transistor Based on Indium-Gallium-Zinc Oxide via Bi2Te3 Light Absorption Layer.

To emulate a visual perception system, a bismuth telluride (Bi2Te3)/indium-gallium-zinc oxide (IGZO) heterostructure is introduced for optoelectronic neuromorphic transistors (ONTs). Amorphous IGZO is applied as a channel layer to exhibit low off-current, high mobility, and persistent photoconductivity, enabling light-stimulated neuromorphic characteristics. The atomic ratio of In/Ga/Zn was 9.4:9.8:5.2. For a light absorption layer, Bi2Te3 is applied due to a small bandgap, high photoresponse, and carrier concentration. However, conventional optoelectronic devices using Bi2Te3 exhibit insufficient performance owing to their excessive conductivity. To resolve the constraint, the oxidation of Bi2Te3 is performed to suppress its electrical conductivity. Finally, the IGZO ONT with a Bi2Te3 layer exhibits optoelectronic characteristics under visible-light irradiation. Under red-light irradiation having a light intensity of 5 mW mm-2, it exhibits enhanced optoelectronic characteristics including photoresponsivity, photosensitivity, and detectivity from 19.6 to 3.46 × 102 A/W, 4.95 to 1.46 × 108, and 1.45 × 107 to 2.13 × 1012 Jones compared to that without a Bi2Te3 layer, respectively. To confirm reproducibility and uniformity, we fabricated and compared the optoelectronic characteristics of 5 samples from batch to batch. Regarding optoelectronic neuromorphic characteristics, the ONT exhibits short- and long-term memory and a highly linear relationship between peak synaptic current and pulse number under red-light pulses. The paired-pulse facilitation index was 208%. To confirm the applicability of artificial visual perception, a 6 × 6 ONT array demonstrates long-term memory characteristic successfully after red-light irradiation with a Y-shaped pattern. In view of stability and reliability, we conducted three potentiation processes and compared the peak synaptic currents of each potentiation process.

Boosting Carrier Mobility in Novel Naphthodithiophene Diimide (NDTI)‐Based Triad Through π‐Conjugation Expansion

AbstractEnhancing the length of π‐conjugation in molecules represents an efficient strategy for fine‐tuning the optoelectronic characteristics of organic semiconductors. Nevertheless, this approach is infrequently conducted for small molecules with n‐type properties. Herein, we report the design and synthesis of a novel naphthodithiophene diimide (NDTI)‐based small‐molecule semiconductor, NDTI‐BBTE, featuring a long benzo[b]thiophen‐2‐ylethynyl (BTE) end cap. NDTI‐BBTE exhibits good solubility in some common organic solvents and a LUMO energy level of −4.15 eV, promoting stable electron transport in ambient conditions. Compared to our previously reported NDTI‐BET with a thiophenylethynyl end cap, NDTI‐BBTE shows improved device performance, achieving a maximum electron mobility of 0.052 cm2 V⁻¹ s⁻¹ under identical conditions. The XRD and AFM measurements reveal that NDTI‐BBTE has lower d‐spacing and higher crystallinity than NDTI‐BTE. These results demonstrate that increasing π‐conjugation length of the molecules is a simple and effective strategy for designing solution‐processable, air‐stable n‐type organic semiconductors for printed electronics.

Morphological optimization of CuO-Y2O3 BPMO composites for enhanced MIS diode performance

The development of techniques for synthesizing nanomaterials with convertible characteristics has resulted from the need to enhance photodiode performance. In this article, we presented the synthesis of CuO-Y2O3 nanocomposites for optoelectronic applications using feasible low-temperature co-precipitation technique. In A cubic phase structure for pure Y2O3 and a orthorhombic structure for CuO-Y2O3 composite have been proven to exist based on XRD patterns with predominant orientations along the directions (2 2 2) and (1 2 1), respectively. Dual phase polycrystalline structure with cubic and orthorhombic crystals is seen for samples of CuO with Y2O3 of various compositions. In the CuO composite with Y2O3, FESEM images reveal the existence of thorn-like, rectangular, irregular rectangular forms, and discrete shaped particles. The appearance of two predominant stretching vibrations of both CuO-Y2O3 and Y2O3 obtained from the FT-IR spectra at 555 cm−1 and 493 cm−1 respectively. The 75–25 composition of Cu-Y sample has the lowest band-gap energy (1.944 eV), according to UV-DRS spectra. Two significant peaks with binding energies 158.88 eV (for Y3d3/2) and 157.08 eV (for Y3d5/2) are evidenced in the Y3d XPS peak fit. According to the results of the I–V investigation, the p-Si/Al interface contains CuO-Y2O3 nanocomposites, which enhance the MIS diode’s performance. The developed photo-detectors are ideally suited for nano-electronic applications due to their superior optoelectronic characteristics.

Modelling of (N-vinylcarbazole)/Fullerene nanoheterojunction for organic solar cells and photovoltaics applications – A DFT Approach

The current manuscript depicts the construction of a novel hybrid carbon nanomaterials with fascinating electronic and chemical properties and tunable energy bandgap of a nano heterojunction comprising (9-vinyl carbazole), VK and fullerene, C60. A comprehensive investigation of VK/C60 adsorption surface is conducted using ab-initio density functional theory calculations with van der Waals corrections (GGA+vdW) implemented. The novel nanoheterostructure interfaces synthesized by DFT methods have low-bandgap characteristics (1.112–1.223 eV), broaden absorption wavelengths and photovoltaic characteristics. This novel VK/C60 nanoheterostructure composites have finite bandgaps and good stability and, therefore, have promising applications for photovoltaic devices. Optoelectronic features of all three developed systems are recommended for future solar cell applications. The studies reveal that the VK/C60 nanoheterojunctions can behave as efficient electron donor-acceptor components in organic solar cells (OSCs) that make them potential candidates for the development of low-cost optoelectronic devices. The band gap values calculated in this work are low enough to make the nanoheterostructures exceedingly promising for photovoltaic applications.

Tuning the morphology and energy levels in organic solar cells with metal–organic framework nanosheets

Metal–organic framework nanosheets (MONs) have proved themselves to be useful additives for enhancing the performance of a variety of thin film solar cell devices. However, to date only isolated examples have been reported. In this work we take advantage of the modular structure of MONs in order to resolve the effect of their different structural and optoelectronic features on the performance of organic photovoltaic (OPV) devices. Three different MONs were synthesized using different combinations of two porphyrin-based ligands meso-tetracarboxyphenyl porphyrin (TCPP) or tetrapyridyl-porphyrin (TPyP) with either zinc and/or copper ions and the effect of their addition to polythiophene-fullerene (P3HT-PC71BM) OPV devices was investigated. The power conversion efficiency (PCE) of devices was found to approximately double with the addition of MONs of Zn2(ZnTCPP) -4.7% PCE, 10.45 mA/cm2 short-circuit current density (JSC), 0.69 open-circuit voltage (VOC), 64.20% fill-factor (FF), but was unchanged with the addition of Cu2(ZnTPyP) (2.6% PCE, 3.68 mA/cm2JSC, 0.59 VOC, 46.27% FF) and halved upon the addition of Cu2(CuTCPP) (1.24% PCE, 6.72 mA/cm2JSC, 0.59 VOC, 56.24% FF) compared to devices without nanosheets (2.6% PCE, 6.61 mA/cm2JSC, 0.58 VOC, 56.64% FF). Our analysis indicates that there are three different mechanisms by which MONs can influence the photoactive layer – light absorption, energy level alignment, and morphological changes. Analysis of external quantum efficiency, UV–vis and photoelectron spectroscopy data found that MONs have similar effects on light absorption and energy level alignment. However, atomic force and Raman microscopy studies revealed that the nanosheet thickness and lateral size are crucial parameters in enabling the MONs to act as beneficial additives resulting in an improvement of the OPV device performance. We anticipate this study will aid in the design of MONs and other 2D materials for future use in other light harvesting and emitting devices.

Interface Charge Engineering in Ferroelectric Neuristors for a Complete Machine Vision System.

The rapid advancement of artificial intelligence has driven the demand for hardware solutions of neuromorphic pathways to effectively mimic biological functions of the human visual system. However, current machine vision systems (MVSs) fail to fully replicate retinal functions and lack the ability to update weights through all-optical pulses. Here, by employing rational interface charge engineering via varying the charge trapping layer thickness of PMMA, we determine that the ferroelectric polarization of our ferroelectric neuristors can be flexibly manipulated through light or electrical pulses. This capability enables dynamic modulation of the device's optoelectronic characteristics, facilitating a complete MVS. As front-end sensors, devices with the thickest PMMA (∼32 nm) demonstrate autonomous light adaptation while those with the thinnest PMMA (∼2 nm) exhibit bidirectional photoresponse characteristics akin to those of bipolar cells. Furthermore, as components of a back-end processor, the conductances of these devices with a moderate thickness (∼12 nm) can be updated linearly through all-optical pulses. Our MVS, constructed with these neuristors, achieved an impressive recognition accuracy of 93% in handwritten digit recognition tasks under extreme lighting conditions. This work offers an effective strategy for the development of energy-efficient and highly integrated intelligent MVSs.

Optimizing Light Sensing Capabilities of WSe2 FETs through Chemical Modulation of Carrier Dynamics

Two-dimensional semiconductor materials demonstrate interesting electronic and optoelectronic properties, which can be further modulated through chemical doping to control carrier concentration and enhance device performance. This study explores the doping process of a few-layer thin WSe2 using FeCl3 solution as a dopant. We perform a thorough characterization utilizing Raman analysis and electrical testing to validate the doping of WSe2. The investigations reveal the p-type doping effect and a notable rise in hole concentration, further elucidated via the energy band diagram. Additionally, the WSe2 field-effect transistor (FET) operation is investigated under illumination with light of different wavelengths ranging from 220 nm to 514 nm both before and after doping. Following p-type doping, the device exhibited a notable increase in current, indicative of improved performance in photodetection. The responsivity and external quantum efficiency (EQE) are improved significantly after doping. This research confirms the effectiveness of p-type doping in WSe2 and highlights its impact in enhancing the electronic and optoelectronic characteristics of WSe2 devices. The results underscore the potential for advancing electronic and optoelectronic applications through such enhancements.

Development of ternary PANI/GO-Fe3O4@AgNps nanocomposites for photocatalytic remediation of toxic dye effluent under energy-efficient system

The environmental toxicity of effluents contaminated with synthetic industrial dyes and their resistance to conventional treatments drive the need for developing innovative treatment technologies such as visible photoactive catalysts in a photocatalytic system. In this study, novel nanocomposite photocatalysts were synthesized for photocatalytic remediation of toxic dye effluent under energy-efficient Light Emitting Diode (LED) irradiation. Concise instrumental analysis was used to investigate the morphological, functional, particle size, thermal and optoelectronic features of the developed photocatalytic nanocomposites. Their performance was tested with cationic (methylene blue) and anionic (methyl orange) model dyes. The instrumental elucidation reveals the coating of amorphous polyaniline with other composites, giving the blend rapid reactivity, which promotes photocatalyst-dye interaction. The composites exhibit lowered bandgap (2.66 eV, 2.85 eV and 2.27 eV) when compared to polyaniline (3.34 eV) used as macromolecular support via in situ coupling. This accounts for the efficiency of 95 % and 98 % reported for methylene blue and methylene orange, respectively, at optimal experimental conditions of 90 min irradiation time, pH of 5 and dosage of 20 mg/100 mL dye effluent. The study also proposed a Z-scheme mechanism with the vital role of •O2 –, •OH and h+ reactive species in the photodegradation of the dye molecules.

Photodegradation of mixed organic dyes and ciprofloxacin antibiotic using spray pyrolyzed Li-Nb co-doped SnO2 thin films

Immobilized photocatalysts are emerging in prominence for photocatalytic degradation of various kinds of harmful pollutants. In order to tune SnO2 thin films as an effective transparent conducting photoelectrode towards photocatalytic degradation, the effects of lithium and niobium co-doping are examined for their structural, morphological, and optoelectronic characteristics. X-ray diffraction patterns reveal successful doping of ‘Nb’ and ‘Li’ into the SnO2 lattice rendering highly textured growth along (110), (200), (310), and (220) plane directions. X-ray photoelectron spectroscopy confirmed the charge states of Sn4+, Nb5+, O2-, and Li1+ elements to be present in the co-doped SnO2 films. FESEM micrographs reveal that the tetragonal shaped particles (0 - 1 wt.% Li doped Nb(2 wt.%):SnO2) undergo a mild agglomeration by forming more slender grains (2 - 4 wt.% Li doped Nb(2 wt.%):SnO2). The wettability nature by contact angle measurement indicates all the films to be hydrophilic in nature. Nb and Li codoping into the SnO2 lattice enhances the transmittance from 53 % for pure to 72 % for 4 wt.% Li and 2 wt.% Nb codoped SnO2 thin film. Photoluminescence emission intensity has been suppressed by the substitution of Nb and Li into the SnO2 films. Linear four-probe and Hall effect revealed sheet resistance and electrical transport properties with a minimum sheet resistance of 56 Ω/□ and with highest mobility of 34.75 cm2 V-1s-1 for 4 wt. % Li and 2 wt.% Nb doped SnO2 thin film, respectively. Based on the determined optoelectronic properties, the photocatalytic activity for solely methyl violet, mixed dyes (methyl orange, malachite green, and methylene blue), and ciprofloxacin antibiotic degradation was carried out using optimal film (1 wt.% Li: 2 wt.% Nb co-doped SnO2), and a significant degradation efficiency was achieved in both Sunlight and LED light illumination.

A facile approach for fabricating efficient and stable perovskite solar cells.

Perovskite solar cells (PSCs) with high power conversion efficiencies (PCEs) can be produced using a variety of methods, such as different fabrication methods, device layout modification, and component and interface engineering. The efficiency of a perovskite solar cell is largely dependent on the overall quality of the perovskite thin-film in every scenario. The utilization of spin-coating followed by the antisolvent pouring (ASP) method is prevalent in nearly all fabrication techniques to achieve superior perovskite thin-films. Nevertheless, there are a few guidelines that must be followed precisely when using the ASP approach, including the antisolvent amount, duration, and area for dropping. The aforementioned challenging and necessary strategies frequently result in perovskite thin-films with pinholes, tiny grains, and broad grain boundaries, which impair the performance of PSCs. Therefore, the implementation of a straightforward approach that does not require the use of such complex ASP steps is crucial. Here, we employ a simple process that involves the hot-dipping of lead iodide (PbI2) thin-films in a hot solution of methylammonium iodide (MAI) and formamidinium iodide (FAI) in isopropanol (IPA) to produce high-quality perovskite thin-films. As the time required for the desired perovskite to crystallize is critical, we carefully examined various hot-dipping process times, such as 10 seconds, 20 seconds, 30 seconds, and 40 seconds. These time intervals yielded thin-films, which were named PSK-10, PSK-20, PSK-30, and PSK-40, respectively. Morphological and optoelectronic characterization demonstrated the high quality of the perovskite thin-films obtained through dipping PbI2 for 30 seconds. Consequently, the PSK-30-based PSCs produced higher PCEs of up to 21.52% compared to those of the ASP-based devices (20.79%). Furthermore, the unsealed PSCs prepared with PSK-30 and ASP were assessed for 252 hours at 25 °C and 40-45% relative humidity in order to determine their operational stability. The ASP-based device showed poor stability, retaining only 10% of its original PCE, whereas the PSK-30-based device retained 70% of its initial PCE. These results offer a new and viable approach for producing highly efficient and stable PSCs.

A high-throughput and data-driven computational framework for novel quantum materials

Two-dimensional layered materials, such as transition metal dichalcogenides (TMDs), possess an intrinsic van der Waals gap at the layer interface, allowing for remarkable tunability of the optoelectronic features via external intercalation of foreign guests such as atoms, ions, or molecules. Herein, we introduce a high-throughput, data-driven computational framework for the design of novel quantum materials derived from intercalating planar conjugated organic molecules into bilayer transition metal dichalcogenides and dioxides. By combining first-principles methods, material informatics, and machine learning, we characterize the energetic and mechanical stability of this new class of materials and identify the fifty (50) most stable hybrid materials from a vast configurational space comprising ∼105 materials, employing intercalation energy as the screening criterion.

Systematic study of spin dependent electronic, mechanical, optoelectronic and thermoelectric properties of halide double perovskites K2CuCrZ6 (Z = Cl, Br): DFT-calculations

Since spintronic devices can operate at far higher speeds, with less power consumption, and with unlimited durability, it is a developing subject that might eventually replace traditional electronics. Double perovskites have strong spin polarization ferromagnetism, which makes them ideal materials for spintronics. Density Functional Theory has been used in the current study to examine the structural, optoelectronic, magnetic, and thermoelectric characteristics of K2CuCrCl6 and K2CuCrBr6. PBE-sol is used to compute exchange correlation potential, and mBJ potential is used to measure bandgap accurately. The two materials demonstrate a cubic structure and thermodynamic stability, as demonstrated by their respective volume optimization and negative formation energy values. Materials that are ferromagnetic can be identified by their exchange constant values and spin-based energy-volume optimization. It has been noted that the primary contribution in net magnetic moment resulting from exchange splitting and the source for ferromagnetism is the 3-d states of Cr. Additionally, studies of band structure and density-of-states reveal that materials are semiconducting, having indirect bandgap values of 1.3 eV and 1.2 eV for K2CuCrCl6 and K2CuCrBr6, respectively, and substantial ultraviolet absorption in the optical spectra of the materials. In conclusion, the study of thermoelectric characteristics involves the assessment of thermal and electrical conductivities, Seebeck coefficient, power factor, and figure of merit (ZT). K2CuCrCl6 and K2CuCrBr6 both exhibit a high ZT, with values of 0.77 and 0.71, respectively. The findings of electronic and magnetic characteristics of K₂CuCrZ₆ (Z = Cl, Br) reveal that these investigated materials hold significant potential for applications in advanced technologies like spintronic and optoelectronic devices in which their stability and tunable magnetic behavior could be leveraged to develop versatile and more efficient components.

High-performance Teraherz photodetection in 2D materials and topological materials

Abstract Photodetectors leveraging two-dimensional (2D) materials and topological materials have garnered substantial interest due to their exceptional electronic and optoelectronic characteristics. These materials, including 2D semimetals like graphene, semiconducting transition metal dichalcogenides, and topological insulators such as bismuth selenide, exhibit a broad array of bandgap values and unique photon interaction properties. To date, numerous high-performance photodetectors using these materials have been documented, showing significant potential in terahertz (THz) frequency applications. This review presents a comprehensive examination of photodetectors based on 2D and topological materials, focusing on the THz frequency. Initially, an insight into the photocurrent generation mechanisms within these materials is provided, alongside a discussion of the figure-of-merits, such as responsivity and detectivity, which are crucial for evaluating photodetector performance. The recent advancements in THz photodetection are then highlighted, noting exceptional attributes such as high sensitivity, ultrafast response, broad spectral operation, and anisotropic detection capabilities, based on cutting-edge devices. Early-stage applications and the integration potential of these photodetectors in various technologies are also explored. Concluding, the manuscript offers a forward-looking perspective, outlining ongoing challenges, future research directions, and practical advice for developing next-generation THz photodetectors, aiming to inspire continued innovation in this rapidly evolving field.

Triphenylamine-Based Y-Shaped Self-Assembled Monolayers for Efficient Tin Perovskite Solar Cells.

Triphenylamine-based Y-shaped organic sensitizers, specifically TPA-MN (1), TPA-CA (2), TPAT-MN (3), and TPAT-CA (4), are synthesized and utilized as p-type self-assembled monolayers (SAMs) for tin-based perovskite solar cells (TPSCs). These SAMs are developed using low-cost starting materials, primarily from triphenylamine (TPA) components. An extensive analysis is conducted to examine the crystalline, morphological, thermal, optical, electrochemical, and optoelectronic characteristics of SAMs 1-4, and the results are compared. A two-step method is employed to successfully develop tin perovskite layers on all four SAM surfaces. The resulting devices demonstrates PCE in the following order: TPAT-CA (8.1%) > TPAT-MN (6.1%) > TPA-MN (5.0%) > TPA-CA (4.2%). The TPAT-CA molecule, which contains a thiophene spacer, performed better than the other three SAMs in terms of rapid hole extraction rate, high hole mobility, and retarded charge recombination. Consequently, SAM TPAT-CA exhibited the highest device performance with excellent stability over time, retaining ≈90% from the beginning values after storage for 3000 h. The innovative Y-shaped SAMs describe in this study, characterized by their simple and efficient design, have the potential to contribute significantly to the advancement of perovskite photovoltaics, particularly in the development of cost-effective TPSC technology.

Optoelectronic performance prediction of HgCdTe homojunction photodetector in long wave infrared spectral region using traditional simulations and machine learning models

This research explores the design of an infrared (IR) photodetector using mercury cadmium telluride (Hg1–xCdxTe). It proposes two- and three-dimensional homojunction models based on p+-Hg0.7783Cd0.2217Te/n–-Hg0.7783Cd0.2217Te, focusing on applications in the long-wavelength infrared range. The photodetector’s performance is analyzed using Silvaco ATLAS TCAD software and compared with analytical calculations based on drift-diffusion, tunneling, and Chu’s approximation techniques. Optimized for operation at 10.6 μm wavelength under liquid nitrogen temperature, the proposed photodetector demonstrates promising optoelectronic characteristics including the dark current density of 0.20 mA/cm2, photocurrent density of 4.98 A/cm2, and photocurrent density-to-dark current density ratio of 2.46 × 104, a 3-dB cut-off frequency of 104 GHz, a rise time of 0.8 ps, quantum efficiency of 58.30 %, peak photocurrent responsivity of 4.98 A/W, specific detectivity of 3.96 × 1011 cmHz1/2/W, and noise equivalent power of 2.52 × 10–16 W/Hz1/2 indicating its potential for low-noise, high-frequency and fast-switching applications. The study also incorporates machine learning regression models to validate simulation results and provide a predictive framework for performance optimization, evaluating these models using various statistical metrics. This comprehensive approach demonstrates the synergy between advanced materials science and computational techniques in developing next-generation optoelectronic devices. By combining theoretical modeling, simulation, and machine learning, the research highlights the potential to accelerate progress in IR detection technology and enhance device performance and efficiency. This multidisciplinary methodology could serve as a model for future studies in optoelectronics, illustrating how advanced materials and computational methods can be utilized to enhance device capabilities.

Tunable electronic and optoelectronic characteristics of two-dimensional β-AsP monolayer: a first-principles study.

Two-dimensional (2D) semiconductors have attracted a great deal of interest from the electrical engineering community due to their intriguing electronic properties. In this study, we have systematically investigated the electronic and optoelectronic properties of β-AsP monolayers by first-principles calculations combined with strain engineering. The results show that the β-AsP monolayer has a suitable indirect bandgap and a strain-tunable electronic structure. On this basis, the designed two-electrode photodetector based on β-AsP monolayer exhibits a strong photoelectric response in the near-ultraviolet region, and the maximum photocurrent can reach 74a02 per phonon under the applied bias voltage of 1 V. In particular, the strain engineering not only improves the photoelectric performance of the β-AsP-based photodetector, but also adjusts its photodetection range. These findings suggest that β-AsP monolayers are ideal candidates for the development of near-ultraviolet photodetectors and optoelectronic devices.