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Organic-inorganic hybrids are next-generation materials for use in high-performance optoelectronic devices owing to their adaptabilities in terms of design and properties. This article reviews the application of hybrid materials and layers in several widely used optoelectronic devices, i.e., light amplification by stimulated emission of radiation (LASER), solar cells, and light-emitting diodes (LEDs). The effects of the incorporation of inorganic particles on photostability and optical gain are analyzed in the first section with reference to dye and perovskite lasers. Second, the strategies used in blending inorganic nanostructures into organic solar cells and bulk heterojunctions are analyzed. The use of various organic layers as electron- and hole-transport materials in Si heterojunction solar cells is reviewed in detail. Finally, the benefits of the presence of organic components in quantum-dot- and perovskite-based LEDs are derived from the analysis. The integration of organic and inorganic components with optimal interfaces and morphologies is a challenge in developing hybrid materials with improved efficiencies.

Physical observation of electrochemical metallization (ECM) channel is required for understanding the electrical characteristics of ECM memristors. Although numerous studies have explored to identify the ECM channels, the majority of approaches have been limited to in-situ systems and localized areas, lacking a comprehensive demonstration of their findings. This study focuses on interpreting the different electrical characteristics of ECM memristors through identification of ECM channels using a new method inspired by etch pit detection on Si surface for determining copper contamination. Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) were utilized to detect and analyze conductive channels within the switching medium after real operation. Interestingly, devices with insulating amorphous carbon (a-C) as medium layer exhibited multiple channels, while devices with semiconducting a-C layers showed a single channel in the on-state. Furthermore, devices with a single channel demonstrated more uniform switching parameters, including high resistance state and set voltage, compared to devices with multiple channels. However, devices with multiple channels exhibited better retention properties.In addition, intermetallic conductive channels were confirmed, resulting from the mixing of Cu active metal ions with the Pt bottom electrode in high current density conditions. The findings of this work provide valuable insights into interpreting ECM memristor performance based on the formation of channels and inspire device design strategies for improving device performance. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrids are next-generation materials for use in high-performance optoelectronic devices owing to their adaptabilities in terms of design and properties. This article reviews the application of hybrid materials and layers in several widely used optoelectronic devices, i.e., light amplification by stimulated emission of radiation (LASER), solar cells, and light-emitting diodes (LEDs). The effects of the incorporation of inorganic particles on photostability and optical gain are analyzed in the first section with reference to dye and perovskite lasers. Second, the strategies used in blending inorganic nanostructures into organic solar cells and bulk heterojunctions are analyzed. The use of various organic layers as electron- and hole-transport materials in Si heterojunction solar cells is reviewed in detail. Finally, the benefits of the presence of organic components in quantum-dot- and perovskite-based LEDs are derived from the analysis. The integration of organic and inorganic components with optimal interfaces and morphologies is a challenge in developing hybrid materials with improved efficiencies. [ABSTRACT FROM AUTHOR]

Ternary copolymerization is a cost‐effective and time‐saving approach to improve device performance and batch stability of polymer donors. However, the structure of the ternary polymer donor obtained by the traditional one‐pot polymerization is vague due to the different monomer reaction order, which has a great influence on the absorption, crystallization, molecular stacking, and device performance. Therefore, it is necessary to obtain terpolymers with definite structures, and systematically study the differences in device properties of polymers with different sequence structures. Herein, three terpolymers D1, D2, and D3 are developed. Random copolymer D3 is obtained via the traditional one‐pot method while alternating copolymer donor D1 and block copolymer D2 are synthesized by stepwise polymerization. Because the block copolymer D2 possess periodic sequence distribution and retains the excellent properties of the two polymer matrix very well, the D2‐based device shows enhanced tightened π‐face‐on molecular stacking, distinguished efficient exciton dissociation, and decreased energy loss. As a result, the D2:L8‐BO‐based polymer solar cells achieve one of a record power conversion efficiency of 19.03%. The work demonstrates changing the sequence structure of the polymers to synthesize well‐defined structures polymer donors not only maintains the features of polymer matrix, but also combines the advantages of ternary copolymerization. [ABSTRACT FROM AUTHOR]

With the booming growth of artificial intelligence (AI), the traditional von Neumann computing architecture based on complementary metal oxide semiconductor devices are facing memory wall and power wall. Memristor based in-memory computing can potentially overcome the current bottleneck of computer and achieve hardware breakthrough. In this review, the recent progress of memory devices in material and structure design, device performance and applications are summarized. Various resistive switching materials, including electrodes, binary oxides, perovskites, organics, and two-dimensional materials, are presented and their role in the memristor are discussed. Subsequently, the construction of shaped electrodes, the design of functional layer and other factors influencing the device performance are analyzed. We focus on the modulation of the resistances and the effective methods to enhance the performance. Furthermore, synaptic plasticity, optical-electrical properties, the fashionable applications in logic operation and analog calculation are introduced. Finally, some critical issues such as the resistive switching mechanism, multi-sensory fusion, system-level optimization are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACTWith the booming growth of artificial intelligence (AI), the traditional von Neumann computing architecture based on complementary metal oxide semiconductor devices are facing memory wall and power wall. Memristor based in-memory computing can potentially overcome the current bottleneck of computer and achieve hardware breakthrough. In this review, the recent progress of memory devices in material and structure design, device performance and applications are summarized. Various resistive switching materials, including electrodes, binary oxides, perovskites, organics, and two-dimensional materials, are presented and their role in the memristor are discussed. Subsequently, the construction of shaped electrodes, the design of functional layer and other factors influencing the device performance are analyzed. We focus on the modulation of the resistances and the effective methods to enhance the performance. Furthermore, synaptic plasticity, optical-electrical properties, the fashionable applications in logic operation and analog calculation are introduced. Finally, some critical issues such as the resistive switching mechanism, multi-sensory fusion, system-level optimization are discussed.

2D Ti3C2Tx MXene, possessing facile preparation, high electrical conductivity, flexibility, and solution processability, shows good application potential for enhancing device performance of perovskite solar cells (PVSCs). In this study, tetrabutylammonium bromide functionalized Ti3C2Tx (TBAB‐Ti3C2Tx) is developed as cathode buffer layer (CBL) to regulate the PCBM/Ag cathode interfacial property for the first time. By virtue of the charge transfer from TBAB to Ti3C2Tx demonstrated by electron paramagnetic resonance and density functional theory, the TBAB‐Ti3C2Tx CBL with high electrical conductivity exhibits significantly reduced work function of 3.9 eV, which enables optimization of energy level alignment and enhancement of charge extraction. Moreover, the TBAB‐Ti3C2Tx CBL can effectively inhibit the migration of iodine ions from perovskite layer to Ag cathode, which synergistically suppresses defect states and reduce charge recombination. Consequently, utilizing MAPbI3 perovskite without post‐treatment, the TBAB‐Ti3C2Tx based device exhibits a dramatically improved power conversion efficiency of 21.65% with significantly improved operational stability, which is one of the best efficiencies reported for the devices based on MAPbI3/PCBM with different CBLs. These results indicate that TBAB‐Ti3C2Tx shall be a promising CBL for high‐performance inverted PVSCs and inspire the further applications of quaternary ammonium functionalized MXenes in PVSCs. [ABSTRACT FROM AUTHOR]

Hole transport materials in heterojunction solar cells (e. g. perovskite solar cells (PSCs)) play critical roles in determining charge transport dynamics, photovoltaic performance and device stability. This review will present an overview ranging from the structural design and compositional engineering to the stability optimization. Different approaches in managing material structures and doping composition have been summarized in both regular and inverted PSCs, in order to modulate the film morphology, density, conductivity and device reliability. The future research trends and the challenges of hole transport materials are discussed in detail. [Display omitted] Charge transport materials in heterojunction solar cells (e.g. perovskite solar cells (PSCs)) play critical roles in determining charge dynamics, photovoltaic performance and device stability. Currently, the conventional hole transport materials (HTMs), spiro-OMeTAD and PTAA, exhibit remarkable power conversion efficiencies in PSCs owing to high thin-film quality and matched energy alignment. However, they often show high material cost, low carrier mobility and poor stability, which greatly limit their practical applications. Tremendous efforts have been devoted to design of alternative low-cost HTMs and to engineer the doping composition. This review summarizes recent advances made in structural optimization and doping engineering of organic HTMs for efficient and stable PSCs. It begins with fundamental roles of HTMs in different device architectures, followed by the strategies to tune the charge dynamics through optimizing the molecular structures and properties. The working principles of the dopants and additives are discussed to provide a comprehensive understanding of compositional roles in device efficiency and stability. Different approaches in managing material structures and doping composition to improve the device reliability have been summarized in both regular and inverted PSCs. Moreover, mechanical stability and scalable deposition techniques are briefly discussed. Finally, we give our perspectives on the ways to further develop efficient and stable HTMs for PSCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interface engineering in solution processed perovskite solar cell is reported using a novel MOF/Composite material. • Density functional simulation indicates the presence of more states for the electron dopingwhich can improve the electron transport across the interface in the device. • Interfacial dipoles modifying the capacitance behaviour as well as charge transport as well as the device performance. Interface engineering is a domineering factor to boost the charge carrier extraction ability in metal-halide perovskite solar cells (PSCs). Modifying the interface of the perovskite absorber layer and electron transfer layer (ETL) with a novel metal-organic framework (MOF) is a promising approach to enhancing the charge transfer ability of tin oxide ETL. This modification of ETL aided the better growth of perovskite films by lowering the trap states. As a result of this, an improvement in device efficiency was observed by ∼ 12 %. The different capacitive behaviour has been explored to understand the charge accumulation and transport properties. The impedance and capacitive responses upon variation of bias voltage as well as frequency are studied. Furthermore, density functional simulation findings were used to understand the dynamic nature UiO-66-NDC/GO composite system in support of the experimental observations. The presence of delocalized surface states in the system has contributed to the enhancement of device performance. A deep mechanistic understanding of interface engineering by UiO-66-NDC/GO has been provided as an approach to improve device performance. [ABSTRACT FROM AUTHOR]

Perovskite materials have demonstrated excellent performance in the field of solar cells, and the device efficiency has already exceeded 25%. However, to date, perovskite solar cells (PSCs) have not been able to achieve large‐scale production. The biggest obstacle to commercializing PSCs is the stability problem that has been widely criticized since their inception. In the last 5 years, the emergence of 2D/3D perovskites has provided a new way to solve this problem. In this review, the representative work on 2D/3D perovskites is summarized, focusing on how 2D/3D structures can simultaneously improve device efficiency and stability. Starting from materials, the current perovskite material system with 2D/3D structure, as well as the bulky organic molecules used to prepare 2D/3D perovskites, is summarized and the corresponding preparation methods are discussed. After that, the influence of the 2D/3D structure on the crystallization of perovskites, the passivation, stabilization, and protection of 2D perovskite on 3D perovskite, and the mechanism of the 2D/3D perovskite heterojunction are discussed in depth. In the end, the development of 2D/3D perovskite from the aspects of research status, advantages, problems encountered, and future research directions is analyzed and prospected. [ABSTRACT FROM AUTHOR]

Advances in organic materials manufacturing have enabled the creation of electronic devices using solution‐processing techniques by employing soluble materials with high conductivity grade. In this exploratory study, the use of micro‐contact for poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer ink deposition as high‐quality structured electrodes for organic field‐effect transistors (OFETs) in top‐contact geometry is demonstrated. The optimized OFET's solution‐processed fabrication is a promising strategy to be realized in the simple, cost‐effective roll‐to‐roll manufacturing processes. The electrical performance of the fabricated devices is comparable to transistors with gold electrodes prepared via vacuum deposition, and even exceeding the values of the charge carriers' mobilities and featuring lower contact resistance (Rc), due to lower charge‐carrier injection barrier for carbon‐based organic electrodes. An addition of multi‐walled carbon nanotubes to the PEDOT:PSS decreases Rc even further, changing the work function for better energy alignment with semiconductor materials. [ABSTRACT FROM AUTHOR]

Abstract Advances in organic materials manufacturing have enabled the creation of electronic devices using solution‐processing techniques by employing soluble materials with high conductivity grade. In this exploratory study, the use of micro‐contact for poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer ink deposition as high‐quality structured electrodes for organic field‐effect transistors (OFETs) in top‐contact geometry is demonstrated. The optimized OFET's solution‐processed fabrication is a promising strategy to be realized in the simple, cost‐effective roll‐to‐roll manufacturing processes. The electrical performance of the fabricated devices is comparable to transistors with gold electrodes prepared via vacuum deposition, and even exceeding the values of the charge carriers’ mobilities and featuring lower contact resistance (Rc), due to lower charge‐carrier injection barrier for carbon‐based organic electrodes. An addition of multi‐walled carbon nanotubes to the PEDOT:PSS decreases Rc even further, changing the work function for better energy alignment with semiconductor materials.

Treprostinil palmitil (TP), a prodrug of treprostinil, is being developed as an inhalation powder (TPIP) for the treatment of patients with pulmonary arterial hypertension (PAH) and pulmonary hypertension due to interstitial lung disease (PH-ILD). In ongoing human clinical trials, TPIP is administered via a commercially available high resistance (HR) RS01 capsule-based dry powder inhaler (DPI) device manufactured by Berry Global (formerly Plastiape), which utilizes the patient's inspiratory flow to provide the required energy to deagglomerate and disperse the powder for delivery to their lungs. In this study, we characterized the aerosol performance of TPIP in response to changes in inhalation profiles to model more realistic use scenarios, i.e., for reduced inspiratory volumes and with inhalation acceleration rates that differ from those described in the compendia. The emitted dose of TP for all combinations of inhalation profiles and volumes ranged narrowly between 79 and 89% for the 16 and 32 mg TPIP capsules at the 60 LPM inspiratory flow rate but was reduced to 72–76% for the 16 mg TPIP capsule under the scenarios at the 30 LPM peak inspiratory flow rate. There were no meaningful differences in the fine particle dose (FPD) at all conditions at 60 LPM with the 4 L inhalation volume. The FPD values for the 16 mg TPIP capsule ranged narrowly between 60 and 65% of the loaded dose for all inhalation ramp rates with a 4 L volume and at both extremes of ramp rates for inhalation volumes down to 1 L, while the FPD values for the 32 mg TPIP capsule ranged between 53 and 65% of the loaded dose for all inhalation ramp rates with a 4 L volume and at both extremes of ramp rates for inhalation volumes down to 1 L for the 60 LPM flow rate. At the 30 LPM peak flow rate, the FPD values for the 16 mg TPIP capsule ranged narrowly between 54 and 58% of the loaded dose at both extremes of the ramp rates for inhalation volumes down to 1 L. Based on these in vitro findings, the TPIP delivery system appears not to be affected by the changes in inspiratory flow profiles or inspiratory volumes that might be expected to occur in patients with PAH or PH associated with underlying lung conditions such as ILD. [ABSTRACT FROM AUTHOR]

Goal: In this study, we investigated the feasibility of predicting the performance of a specific guidewire in terms of its ability to cover a lesion cap surface and apply force to the lesion for a given patient's vessel anatomy. The aim of this research was to provide information that could be used to plan occlusion crossings and peripheral revascularization procedures preoperatively in a way that reduces the risk of potential intraoperative complications and increases the likelihood of success. Methods: We used finite element (FE) analysis to simulate the interaction between the guidewire and a model of a tortuous vessel, and we used this simulation to predict the reachable workspace and deliverable forces of the device for various entry positions and angles. We then validated these predictions through experiments in which we advanced a guidewire through an identical vessel phantom using a robotic manipulator. Conclusions: Our findings suggest that it may be possible to predict the performance of a guidewire and forecast the likelihood of success or failure for a given vessel anatomy and lesion morphology, which could enable improved planning and device selection.

Two-dimensional (2D) semiconductors are emerging as promising candidates for the next-generation nanoelectronics. As a type of unique channel materials, 2D semiconducting transition metal dichalcogenides (TMDCs), such as MoS2 and WS2, exhibit great potential for the state-of-the-art field-effect transistors owing to their atomically thin thicknesses, dangling-band free surfaces, and abundant band structures. Even so, the device performances of 2D semiconducting TMDCs are still failing to reach the theoretical values so far, which is attributed to the intrinsic defects, excessive doping, and daunting contacts between electrodes and channels. In this article, we review the up-to-date three strategies for improving the device performances of 2D semiconducting TMDCs: (i) the controllable synthesis of wafer-scale 2D semiconducting TMDCs single crystals to reduce the evolution of grain boundaries, (ii) the ingenious doping of 2D semiconducting TMDCs to modulate the band structures and suppress the impurity scatterings, and (iii) the optimization design of interfacial contacts between electrodes and channels to reduce the Schottky barrier heights and contact resistances. In the end, the challenges regarding the improvement of device performances of 2D semiconducting TMDCs are highlighted, and the further research directions are also proposed. We believe that this review is comprehensive and insightful for downscaling the electronic devices and extending the Moore's law. [ABSTRACT FROM AUTHOR]

This research theoretically and experimentally develops a hollow-fiber dialysis module coupled with ultrafiltration operations by introducing a trans-membrane pressure during the membrane dialysis process, which can be applied to the waste metabolic end products in the human body for improving the dialysis efficiency. The solutes were transported by both diffusion and convection from the concentration driving-force gradient between retentate and dialysate phases across the membrane, compared to the traditional dialysis processes by diffusion only. A two-dimensional modeling of such a dialysis-and-ultrafiltration system in the hollow-fiber dialysis module was formulated and solved using the stream function coupled with the perturbation method to obtain the velocity distributions of retentate and dialysate phases, respectively. The purpose of the present work is to investigate the effect of ultrafiltration on the dialysis rate in the hollow-fiber dialyzer with ultrafiltration operations. A highest level of dialysis rate improvement up to about seven times (say 674.65% under Va=20 mL/min) was found in the module with ultrafiltration rate Vw=10 mL/min and membrane sieving coefficient θ=1, compared to that in the system without operating ultrafiltration. Considerable dialysis rate improvements on mass transfer were obtained by implementing a hollow-fiber dialysis-and-ultrafiltration system, instead of using the hollow-fiber dialyzer without ultrafiltration operation. The experimental runs were carried out under the same operating conditions for the hollow-fiber dialyzers of the two experimental runs with and without ultrafiltration operations for comparisons. A very reasonable prediction by the proposed mathematical model was observed.

Carbon‐based inorganic perovskite solar cells (C‐PSCs) have attracted intensive attention owing to their low cost and superior thermal stability. However, the bulk defects in perovskites and interfacial energy level mismatch seriously undermine their performance. To overcome these issues, a multifunctional dual‐interface engineering is proposed with a focus on low‐temperature CsPbI2Br C‐PSCs, where the potassium trifluoroacetate (KTFA) and the 4‐trifluorophenyl methylammonium bromide (CF3PMABr) are introduced beneath and on top of the perovskite layer, respectively. It is found that TFA‐ ions locate at the SnO2/CsPbI2Br interface, whereas a small amount of K+ ions diffuse into perovskite lattice to participate in nucleation and crystallization, resulting in more favored interfacial energy level alignment, improved film quality, passivated interfacial defects, released interfacial strain, as well as suppressed charge recombination and ion migration. Meanwhile, the CF3PMABr passivates I/Br vacancies and forms 2D perovskite capping layer to facilitate hole extraction at the CsPbI2Br/carbon interface. As a result, a remarkable power conversion efficiency (PCE) of 14.05% with an open‐circuit voltage of 1.273 V is achieved. To the best of the authors' knowledge, it is currently the highest PCE reported for low‐temperature CsPbI2Br C‐PSCs. Furthermore, the nonencapsulated device exhibits improved moisture, thermal, and illumination stability in ambient air. [ABSTRACT FROM AUTHOR]

Summary: The hole transport layer (HTL) is a vital part in an organic photovoltaic (OPV) device for improving hole extraction ability. The HTL of OPV devices is typically prepared using poly (3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). However, it presents several disadvantages, including causing deterioration of the active layers, exhibiting sensitivity to ultraviolet radiation, and possessing a short lifespan. Hence, focus has increased on alternative p‐type semiconductors with improved environmental stability, easier processing, and higher conductivity. In this study, we prepare water‐stable, low‐cost, and low‐acidity PSS‐doped polypyrrole (PPY) with varying PSS concentrations for use as the HTL in OPV devices. The films formed using PPY:PSS exhibit an extremely high transmittance within the visible range. The PPY:PSS HTL‐based OPV may reach to highest power conversion efficiency of 5.0% (ie, 11% higher than a PEDOT:PSS‐based one) when using an optimal PSS concentration in PPY. [ABSTRACT FROM AUTHOR]

The Silicon Drift Detector (SDD) with square structure is often used in pixel-type SDD arrays to reduce the dead region considerably and to improve the detector performance significantly. Usually, the anode is located in the center of the active region of the SDD with square structure (square-SDD), but the different anode positions in the square-SDD active area are also allowed. In order to explore the effect on device performance when the anode is located at different positions in the square-SDD active region, we designed two different types of square-SDD in this work, where the anode is located either in the center (SDD-1) or at the edge (SDD-2) of its active region. The simulation results of current density and potential distribution show that SDD-1 and SDD-2 have both formed a good electron drift path to make the anode collect electrons. The experimental results of device performance at the temperature range from −60 °C to 60 °C show that the anode current of the two fabricated SDDs both decreased with the decrease of temperature, but their voltage divider characteristics exhibited high stability resistance value and low temperature coefficient, thereby indicating that they could both provide corresponding continuous and uniform electric field at different temperatures. Finally, SDD-1 and SDD-2 have energy resolutions of 248 and 257 eV corresponding to the 5.9 keV photon peak of the Fe-55 radioactive source, respectively. Our experimental results demonstrate that there is no significant impact on the device performance irrespective of the anode positions in the square-SDD devices. [ABSTRACT FROM AUTHOR]

In this study, a ZnO-Fe2O3 thin film was designed as electron transport layer for organic solar cells (OSCs). The preparation strategy was based on the spin coating of aqueous sol–gel precursor. The result showed that composite ZnO-Fe2O3-based OSCs had higher power conversion efficiency than pure ZnO-based OSCs. To explain this result, morphology, optical and physical properties of ZnO-Fe2O3 were investigated to analyze the relation between structure of interface layer and performance of OSCs. It was demonstrated that composite ZnO-Fe2O3 layer had denser structure and lower surface roughness than pure ZnO layer. Thus, it showed a good contact with the active layer. Furthermore, 3.3% Fe2O3 could reduce the WF and Eg of ZnO, and greatly enhanced electron mobility from the acceptor (IT-4F) phase to the ZnO/ITO electrode. Meanwhile, ZnO-Fe2O3 layer showed a low reflectivity that allowed more photons to entrance the active layer for utilization. Hence, the higher short-circuit current and power conversion efficiency were achieved in ZnO-Fe2O3-based OSCs. Highlights: A new aqueous ZnO-Fe2O3 composite sol–gel precursor solution was prepared. ZnO-Fe2O3 was used as electron transport layer for organic solar cells. Efficient organic solar cell could be realized based ZnO-Fe2O3 interface layer. [ABSTRACT FROM AUTHOR]

Fullerene materials have been widely used to fabricate efficient and stable perovskite solar cells (PSCs) due to their excellent electron transport ability, defect passivation effect, and beyond. Recent studies have shown that fullerene-related chemical interaction has played a crucial role in determining device performance. However, the corresponding fullerene-related chemical interactions are yet well understood. Herein, a comprehensive review of fullerene materials in regulating carrier transport, passivating the surface and grain boundary defects, and enhancing device stability is provided. Specifically, the influence of the fullerene-related chemical interactions, including fullerene-perovskite, fullerene-inorganic electron transport layer (IETL), and fullerene-fullerene, on the device performance is well discussed. Finally, we outline some perspectives for further design and application of fullerene materials to enhance the performance and commercial application of PSCs. [ABSTRACT FROM AUTHOR]

Flip chip (FC) light emitting diodes (LEDs) are considered to be more promising in solid state lighting as compared to wire bonded LEDs. For solid-state lighting, thermal management is a very critical factor to enhance the device's performance. In the Flip Chip Light Emitting Diode (LED), the active region is the main source of heat generation. This heat is to be conducted through different layers to the heat sink. The adhesive layer and bump assembly cause heat dissipation because of their low conductivity values and poor transparency and hence cause degradation in performance of FC-LEDs. In this paper, thermal analysis of flip chip LED is done to find out how material, size of die and bumps affect the thermal performance of FC-LED. A flip chip LED structure is modeled on a GaN substrate. Different material properties of silicon, gold, and aluminum have been studied to perform the thermal analysis and to see the effects of different die sizes, bump sizes, and adhesive materials. Thermal analysis of the high-power FC LED by using the Finite Element Method is done on Ansys Software. The FC structure and its meshing design are presented.Temperature variation with different sizes of bump, chip-die and different adhesives (silver filled epoxy, Au-Sn, Pb-Sn) on flip chip LED is discussed. The result shows that thermal heat is directly proportional to the size of the bump and the type of adhesive material selected also affects the performance of FC-LEDto some extent. [ABSTRACT FROM AUTHOR]

Copper(I) thiocyanate (CuSCN) is an effective interlayer material for hole injection and transport in organic electronic devices but its solution processing has conventionally utilized undesirable di‐n‐alkyl sulfide solvents such as diethyl‐ (DES) and dipropyl‐sulfide (DPS). Herein, this paper reports on the use of N,N‐dimethylformamide (DMF) and 1‐methyl‐2‐pyrrolidinone (NMP) as alternative solvents for CuSCN interlayers and performs a detailed comparison of the resulting properties relative to films processed from DES and DPS and two other recent alternatives, dimethyl sulfoxide (DMSO) and ammonium hydroxide. The surface roughness, polymorphism, and surface chemistry of the resulting CuSCN layers are reported. The interlayer surface energy and ionization potential that are key to the overlying semiconductor microstructure and interfacial energy barrier, and hence to charge transport and injection, are also discussed. Finally, systematic device tests using well‐known organic semiconductors in light‐emitting diode, solar cell and field‐effect transistor structures demonstrate the overall suitability of DMSO and DMF as solvents for CuSCN interlayer deposition to achieve better device performance. This study broadens the applicability of CuSCN as a highly efficient hole injection/transport material for organic semiconductor devices by expanding the documented range of suitable CuSCN solvents. [ABSTRACT FROM AUTHOR]

The development of advanced electronic devices is contingent upon sustainable material development and pioneering research breakthroughs. Traditional semiconductor-based electronic technology faces constraints in material thickness scaling and energy efficiency. Atomically thin two-dimensional (2D) transition metal dichalcogenides (TMDs) have emerged as promising candidates for next-generation nanoelectronics and optoelectronic applications, boasting high electron mobility, mechanical strength, and a customizable band gap. Despite these merits, the Fermi level pinning effect introduces uncontrollable Schottky barriers at metal–2D-TMD contacts, challenging prediction through the Schottky-Mott rule. These barriers fundamentally lead to elevated contact resistance and limited current-delivery capability, impeding the enhancement of 2D-TMD transistor and integrated circuit properties. In this review, we succinctly outline the Fermi level pinning effect mechanism and peculiar contact resistance behavior at metal/2D-TMD interfaces. Subsequently, highlights on the recent advances in overcoming contact resistance in 2D-TMDs devices, encompassing interface interaction and hybridization, van der Waals (vdW) contacts, prefabricated metal transfer and charge-transfer doping will be addressed. Finally, the discussion extends to challenges and offers insights into future developmental prospects. [ABSTRACT FROM AUTHOR]

Abstract The molecular orientation has a profound influence on the performance of organic solar cells. Both donor and acceptor adopt face‐on orientation guarantees efficient exciton dissociation and charge transport, which is a key to achieving high device performance. However, the molecules usually adopt edge‐on orientation in some blend systems, take small molecules based on an oligothiophene (DRCN5T): fused‐ring electron acceptor based on indacenodithieno[3,2‐b]‐thiophene core and thienyl side‐chains (ITIC‐Th) blend, for instance, the orientation of DRCN5T is edge‐on, which is detrimental to the photophysical process of the device. Herein, a solid additive strategy, that is, adding N2200 as a nucleus for DRCN5T, was proposed, which combined the nucleation process with molecular diffusivity, thus realizing the orientation transformation of DRCN5T from edge‐on to face‐on. Consequently, the device performance was significantly improved, and a clear relationship between molecular orientation and energy loss/biomolecular recombination was established. More importantly, this study revealed not only the thermodynamic factors, including the crystallinity of solid additive, the lattice matching degree, and miscibility between DRCN5T and solid additive but also the kinetic parameter, such as the diffusivity of DRCN5T are very important to efficiently regulate the molecular orientation. Overall, this study presents the in‐depth mechanism of orientation transformation via adding solid additives, which may provide a guideline for solid additive choices.

Perovskite solar cells (PSCs) have achieved excellent power conversion efficiencies (PCEs); however, there still exist some major challenges on device stability due to hydrophilic bis(trifluoromethane)sulfonimide lithium (Li-TFSI), which is commonly introduced as a p-dopant to increase the hole mobility and conductivity of 2,2′,7,7′-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9′-spirobifluorene (spiro-OMeTAD) hole-transporting materials (HTMs). Ion migration, corrosiveness, and hygroscopicity induced by the additive Li-TFSI are detrimental to the device stability, which significantly hinders further commercialization of PSCs. Herein, a hydrophobic organic ionic compound, trityltetra(pentafluorophenyl)borate (TPP), is explored as a novel efficient and stable alternative p-dopant, avoiding the long-term aging process to improve the conductivity of spiro-OMeTAD. As a result, the champion efficiency of TPP-based devices delivers performance up to 23.03%, which is higher than that of the Li-TFSI–based devices (22.39%). In addition, the TPP-based devices also exhibit higher average PCE values. The excellent performance with TPP may be associated with the higher work function of doped spiro-OMeTAD and a better alignment of energy levels with the valence band of perovskite, which substantially accelerate interfacial carrier transportation and minimize the open-circuit voltage (Voc) loss of PSCs. More importantly, the un-encapsulated TPP-doped devices also display much superior operational stability under maximum power point (MPP) tracking with continuous light illumination in an ambient humid environment, which maintained 96–97% of the initial PCE over 1,100 h outputting. Thus, this work will open up new possibilities for hydrophilic Li-TFSI dopant replacements.

Compared with a two-dimensional (2D) homogeneous channel, the introduction of a 2D/2D homojunction or heterojunction is a promising method to improve the performance of a tunnel field-effect transistor (TFET), mainly by controlling the tunneling barrier. We simulate 10-nm-Lg double-gated GeSe homojunction TFETs and van der Waals (vdW) GeSe/GeTe heterojunction TFETs based on a ballistic quasi-static ab initio quantum transport simulation. Two device configurations are considered for both the homojunction and heterojunction TFETs by placing the bilayer (BL) GeSe or vdW GeSe/GeTe heterojunction as the source or drain, while the channel and the remaining drain or source use monolayer (ML) GeSe. The on-state current (Ion) values of the optimal n-type BL GeSe source homojunction TFET and the optimal p-type vdW GeSe/GeTe drain heterojunction TFET are 2320 and 2387 μA μm−1, respectively, which are 50% and 64% larger than Ion of the ML GeSe homogeneous TFET. Notably, the device performance (Ion, intrinsic delay time τ, and power dissipation PDP) of both the optimal n-type GeSe homojunction and p-type vdW GeSe/GeTe heterojunction TFETs meets the requirements of the International Roadmap for Devices and Systems for high-performance devices for the year 2034 (2020 version). [ABSTRACT FROM AUTHOR]

Treprostinil palmitil (TP) is a prodrug of treprostinil that has been formulated as an inhaled powder, termed TPIP, for evaluation in patients with pulmonary arterial hypertension. In these characterization studies we investigated the aerosol performance of TPIP in response to changes in capsule fill, device resistance, and inspiratory flow rate to enable selection of an inhaler for clinical use. Capsules containing 8, 16 or 32 mg of TPIP (80, 160, or 320 μg TP, respectively) were evaluated using four commercially-available, breath-actuated RS01 devices (Plastiape, S. p.A., Osnago, Italy) with low, medium, high or ultra-high inspiratory resistances, creating 12 different capsule and device configurations for evaluation. Aerosol characterization was performed using the next generation impactor at compendial conditions of 23°C and 35% relative humidity and a flow rate corresponding to a 4 kPa pressure drop. The aerosol mass median aerodynamic diameter, geometric standard deviation, fine particle fraction, emitted dose and fine particle dose (FPD) were calculated from the in vitro impactor data. The TP emitted dose at 4 kPa exceeded 75% for all 12 capsule and device configurations. The FPD, an estimate of the respirable dose, varied between 61.0 and 70.6% of the loaded TP dose for all four devices with the 8 and 16 mg TPIP capsule dose. For the 32 mg TPIP capsule dose, the FPD remained above 61.0% for the high and ultra-high resistance devices but decreased to 48.5 and 52.6% for the low and medium resistance devices, respectively. Based on this initial data, the high resistance device was selected for additional characterization studies at 40 and 80 L/min corresponding to pressure drops of 1.4 and 5.4 kPa. The FPD was relatively insensitive to changes in flow rate, providing an expectation of a consistent total lung dose of TP under scenarios simulating variability in how the device is used. Based on these findings, the high resistance device was chosen for further development in human clinical trials.

Semitransparent organic solar cells (ST‐OSCs) based on all narrow bandgap (all‐NBG) semiconductors are attractive for building integration. Unfortunately, advanced NBG Y‐series acceptors cannot well match with the NBG donors, resulting from their mismatched energy levels and poor compatibility. Herein, a facile terpolymer design strategy is adopted to improve the matching of Y6 with efficient NBG polymer donor PCE10. F or Cl atom functionalized benzodithiophene (BDT) are introduced into the PCE10 matrix to afford two series of terpolymers, namely PCE10‐BDT2F and PCE10‐BDT2Cl. Compared with PCE10, all terpolymers show deeper energy levels, higher extinction coefficients, enhanced face‐on orientation, and better compatibility with Y6. Consequently, significant breakthroughs are achieved for both opaque and semitransparent devices. Particularly, a record power conversion efficiency (PCE) of 13.80% is achieved by PCE10‐BDT2F:Y6‐based device, nearly 40% higher than PCE10:Y6‐based device. ST‐OSCs also achieve impressive PCEs of 12.00% and 10.85% with average visible transmittance (AVT) of 30.98% and 41.08%, respectively, and both PCEs are the highest values with AVT over 30% and 40%. An outstanding light utilization efficiency (LUE) of 4.46% further demonstrates the successful balance of PCE and AVT. These results demonstrate that the design of NBG terpolymers is a facile and highly encouraging strategy for promoting breakthroughs in ST‐OSCs. [ABSTRACT FROM AUTHOR]

Treprostinil palmitil (TP), a prodrug of treprostinil, is being developed as an inhalation powder (TPIP) for the treatment of patients with pulmonary arterial hypertension (PAH) and pulmonary hypertension due to interstitial lung disease (PH-ILD). In ongoing human clinical trials, TPIP is administered via a commercially available high resistance (HR) RS01 capsule-based dry powder inhaler (DPI) device manufactured by Berry Global (formerly Plastiape), which utilizes the patient’s inspiratory flow to provide the required energy to deagglomerate and disperse the powder for delivery to their lungs. In this study, we characterized the aerosol performance of TPIP in response to changes in inhalation profiles to model more realistic use scenarios, i.e., for reduced inspiratory volumes and with inhalation acceleration rates that differ from those described in the compendia. The emitted dose of TP for all combinations of inhalation profiles and volumes ranged narrowly between 79 and 89% for the 16 and 32 mg TPIP capsules at the 60 LPM inspiratory flow rate but was reduced to 72–76% for the 16 mg TPIP capsule under the scenarios at the 30 LPM peak inspiratory flow rate. There were no meaningful differences in the fine particle dose (FPD) at all conditions at 60 LPM with the 4 L inhalation volume. The FPD values for the 16 mg TPIP capsule ranged narrowly between 60 and 65% of the loaded dose for all inhalation ramp rates with a 4 L volume and at both extremes of ramp rates for inhalation volumes down to 1 L, while the FPD values for the 32 mg TPIP capsule ranged between 53 and 65% of the loaded dose for all inhalation ramp rates with a 4 L volume and at both extremes of ramp rates for inhalation volumes down to 1 L for the 60 LPM flow rate. At the 30 LPM peak flow rate, the FPD values for the 16 mg TPIP capsule ranged narrowly between 54 and 58% of the loaded dose at both extremes of the ramp rates for inhalation volumes down to 1 L. Based on these in vitro findings, the TPIP delivery system appears not to be affected by the changes in inspiratory flow profiles or inspiratory volumes that might be expected to occur in patients with PAH or PH associated with underlying lung conditions such as ILD.

This review explores the growing interest in 2D layered materials, such as graphene, h-BN, transition metal dichalcogenides (TMDs), and black phosphorus (BP), with a specific focus on recent advances in strain engineering. Both experimental and theoretical results are delved into, highlighting the potential of strain to modulate physical properties, thereby enhancing device performance. Various strain engineering methods are summarized, and the impact of strain on the electrical, optical, magnetic, thermal, and valleytronic properties of 2D materials is thoroughly examined. Finally, the review concludes by addressing potential applications and challenges in utilizing strain engineering for functional devices, offering valuable insights for further research and applications in optoelectronics, thermionics, and spintronics., (© 2024 Wiley‐VCH GmbH.)

Polymeric semiconductors based on donor-acceptor (D-A) conjugated polymers have emerged as a promising class of materials for various applications due to their excellent solution processability, low cost, and intrinsic flexibility. The use of the indacenodithiophene (IDT) unit as a building block has received significant attention due to its unique pentacyclic ring structure and exceptional photophysical and electronic properties. This review focuses on the latest progress in the field of IDT-based polymers. We discuss the versatility of IDT as a structural molecular engineering tool, along with the use of various electron-deficient acceptors as comonomers and modifications to the IDT structure unit. These advancements have led to improved device performance, particularly in organic electronics applications such as photodetectors, solar cells, field-effect transistors, and thermoelectric devices. In summary, this review serves as a valuable reference for researchers who are interested in creating high-performance polymeric semiconductors using the IDT building block for a range of optoelectronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

The Silicon Drift Detector (SDD) with square structure is often used in pixel-type SDD arrays to reduce the dead region considerably and to improve the detector performance significantly. Usually, the anode is located in the center of the active region of the SDD with square structure (square-SDD), but the different anode positions in the square-SDD active area are also allowed. In order to explore the effect on device performance when the anode is located at different positions in the square-SDD active region, we designed two different types of square-SDD in this work, where the anode is located either in the center (SDD-1) or at the edge (SDD-2) of its active region. The simulation results of current density and potential distribution show that SDD-1 and SDD-2 have both formed a good electron drift path to make the anode collect electrons. The experimental results of device performance at the temperature range from −60 °C to 60 °C show that the anode current of the two fabricated SDDs both decreased with the decrease of temperature, but their voltage divider characteristics exhibited high stability resistance value and low temperature coefficient, thereby indicating that they could both provide corresponding continuous and uniform electric field at different temperatures. Finally, SDD-1 and SDD-2 have energy resolutions of 248 and 257 eV corresponding to the 5.9 keV photon peak of the Fe-55 radioactive source, respectively. Our experimental results demonstrate that there is no significant impact on the device performance irrespective of the anode positions in the square-SDD devices.

• A solution-processed, ultraviolet-irradiation-derived WO 3 layer is developed. • The work function of ITO/WO 3 is increased to 5.13 eV from 4.76 eV of bare ITO. • ITO/WO 3 shows more uniform and hydrophobic surface compared to bare ITO. • ITO/WO 3 -based devices exhibit excellent efficiency of 8.70%. Tungsten(VI) oxide (WO 3) with excellent charge transport properties and intrinsic thermal and chemical robustness is a promising anode interface material instead of PEDOT:PSS in organic solar cells (OSCs). Herein, a solution-processed, ultraviolet-irradiation-derived WO 3 film as anode interface layer (AIL) is developed based on tungsten(VI) chloride (WCl 6) as precursor. The WO 3 film is derived from the solution-processed precursor film with simple ultraviolet-irradiation treatment, and the preparation process without high-temperature annealing is very compatible with large-scale production and flexible substrate. The composition of the WO 3 film is analyzed by X-ray photoelectron spectroscopy. ITO modified by the WO 3 film, namely ITO/WO 3 , exhibits similarly high optical transmittance as that of bare ITO. The work function of ITO/WO 3 measured by ultraviolet photoelectron spectroscopy is obviously lower than that of bare ITO, which can facilitate effective holes extraction. In addition, the WO 3 film possesses relatively smooth and hydrophobic surface, beneficial to form excellent interface contact with active layer. Moreover, non-fullerene OSCs based on the WO 3 film as AIL are studied with typical and relatively low-cost PBDB-T:ITIC as active layer. The optimal efficiency (8.70%) of the device based on ITO/WO 3 is dramatically higher than that (3.32%) of the device based on bare ITO, and comparable to that (8.80%) of the device based on ITO/PEDOT:PSS. Therefore, the solution-processed, ultraviolet-irradiation-derived WO 3 film as AIL should have great potential to realize high-performance non-fullerene OSCs, which can also inspire a novel and promising route to prepare other transition metal oxide films in optoelectronic devices. [ABSTRACT FROM AUTHOR]

We report all-polymer solar cells (All-PSCs) with record-high power conversion efficiency (PCE) through tuning the molecular weights of the polymer donor (PBDB-T) to form optimal active layer morphology. By combining the polymer donors with a newly reported polymer acceptor (PJ1), an unprecedented high PCE of 15.4% and fill factor over 75% were achieved for the All-PSCs with the medium molecular weight polymer donor (PBDB-TMW), which is the highest value for All-PSCs reported so far. Detailed morphology investigation revealed that the proper phase separation in the PBDB-TMW:PJ1 blend should account for the superior device performance as PBDB-TMW exhibits appropriate miscibility with the polymer acceptor PJ1. These results demonstrated that the device performance of All-PSCs could be fully comparable to that of small molecular acceptor-based PSCs. The formation of optimized morphology via precise control of molecular weights of polymer donors and acceptors is crucial to achieve this goal. [ABSTRACT FROM AUTHOR]

• Metallic nanostructure usage supports the localized surface plasmons. • Plasmonic nanostructure enhances the required light absorption. • Metal oxides nanostructures are also good dopant in the active layer of OSC. • Light trapping contributes to an enhanced photocurrent generation in organic solar cells. Silver doped nickel oxide (Ag:NiOx) nanocomposites (NC) were synthesized using a thermal decomposition method for possible application in thin-film organic solar cells. Two different synthesis products were found from the experiment, which have exhibited different characteristics in terms of colour, structure, and optical properties. These nanocomposites (Ag:NiOx) have two distinct colours namely green and black. The green powder contains a trace of carbon element while the black powder is pure Ag:NiOx. Both products were used in device fabrication to assist in photons harvesting at a various concentration of the NC by weight. In all cases, an optimum concentration of 1 wt% of the Ag:NiO x powders were found to yield a maximum power conversion efficiency (PCE) of 4.9% and 5.1% for the green and black powders, respectively. Higher concentrations of Ag:NiOx in the solar absorber layers were found to be unfavorable in improving device performances. Overall, both synthesized metal NCs performed fairly similar and they have improved device performance substantially compared to the reference cells. The experimental results are discussed in terms of optical and electrical properties of the absorber layer as well as charge transport processes. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite solar cells (PSCs) have attracted significant attention in recent years due to their high‐power conversion efficiency, simple fabrication, and low material cost. However, due to their high sensitivity to moisture and oxygen, high efficiency PSCs are mainly constructed in an inert environment. This has led to significant concerns associated with the long‐term stability and manufacturing costs, which are some of the major limitations for the commercialization of this cutting‐edge technology. Over the past few years, excellent progress in fabricating PSCs in ambient conditions has been made. These advancements have drawn considerable research interest in the photovoltaic community and shown great promise for the successful commercialization of efficient and stable PSCs. In this review, after providing an overview to the influence of an ambient fabrication environment on perovskite films, recent advances in fabricating efficient and stable PSCs in ambient conditions are discussed. Along with discussing the underlying challenges and limitations, the most appropriate strategies to fabricate efficient PSCs under ambient conditions are summarized along with multiple roadmaps to assist in the future development of this technology. [ABSTRACT FROM AUTHOR]

The next-generation X-ray detectors require novel semiconductors with low material/fabrication cost, excellent X-ray response characteristics, and robust operational stability. The family of organic-inorganic hybrid perovskites (OIHPs) materials comprises a range of crystal configuration (i.e., films, wafers, and single crystals) with tunable chemical composition, structures, and electronic properties, which can perfectly meet the multiple-stringent requirements of high-energy radiation detection, making them emerging as the cutting-edge candidate for next-generation X-ray detectors. From the perspective of molecular dimensionality, the physicochemical and optoelectronic characteristics of OIHPs exhibit dimensionality-dependent behavior, and thus the structural dimensionality is recognized as the key factor that determines the device performance of OIHPs-based X-ray detectors. Nevertheless, the correlation between dimensionality of OIHPs and performance of their X-ray detectors is still short of theoretical guidance, which become a bottleneck that impedes the development of efficient X-ray detectors. In the review, the advanced studies on the dimensionality engineering of OIHPs are critically assessed in X-ray detection application, discussing the current understanding on the "dimensionality-property" relationship of OIHPs and the state-of-the-art progresses on the dimensionality-engineered OIHPs-based X-ray detector, and highlight the open challenges and future outlook of this field., (© 2023 Wiley‐VCH GmbH.)

Organic-inorganic hybrid perovskites as promising light-harvesting materials have been the focus of scientific research and development of photovoltaics recently. Especially, metal halide perovskites currently become one of the most competitive candidates for the fabrication of solar cells with record certified efficiency over 25%. Despite the high efficiency, many fundamental questions remain unclear and need to be addressed at both the material and device levels, such as weaker stability, poorer reproducibility, easier degradation influenced by water, oxygen, thermal factors, and so on. Based on recent reports, interfacial engineering plays a crucial role in controlling the behavior of the charge carriers and in growing high quality, defect-free perovskite crystals, therefore helping to enhance device performance and operational stability. However, little attention has been paid to the interface interaction mechanism among carrier transport layers and perovskite active layer. It is extremely urgent to explore the perovskite interfaces in details and to find out how its interface structure is relative to the efficiency and hysteresis in perovskites solar cells. Based on the Shanghai Synchrotron Radiation Facility (SSRF), we have established an advanced perovskite photovoltaic device preparation and in-line test system, developed a series of unique surface diffraction analysis methods based on ex situ and in situ grazing incidence X-ray diffraction (GIXRD), and reported a large number of novel synchrotron radiation results on crystallization of the perovskite photovoltaics films. Our main investigations are aimed to deeply in-situ study the perovskite film growth dynamics using synchrotron radiation GIXRD technology in combination with a customized mini online glove box (c(H2O,O2)

Naphthalene diimide (NDI)-based polymer N2200 is a promising organic polymer acceptor for all-polymer solar cells (all-PSCs), but its inherent shortcomings like poor extinction coefficient and strong aggregation limit further performance optimization of all-PSCs. Here, a series of random copolymers, PNDI-Px, were designed and synthesized by introducing porphyrin unit into NDI-based polymer as acceptors for all-PSCs. These random copolymers show a higher absorption coefficient and raised the lowest unoccupied molecular orbital (LUMO) energy levels compared to N2200. The crystallinity can also be fine-tuned by regulation of the content of porphyrin unit. The random copolymers are matched with polymer donor PBDB-T for the application in all-polymer solar cells. The best power conversion efficiency (PCE) of these PNDI-Px-based devices is 5.93%, ascribed to the overall enhanced device parameters compared with the N2200-based device. These results indicate that introducing porphyrin unit into polymer is a useful way to fine-tune the photoelectric performance for efficient all-PSCs.

Organic field-effect transistors (OFETs) are fabricated using organic semiconductors (OSCs) as the active layer in the form of thin films. Due to its advantages of high sensitivity, low cost, compact integration, flexibility, and printability, OFETs have been used extensively in the sensing area. For analysis platforms, the construction of sensing layers is a key element for their efficient detection capability. The strategy used to immobilize biomolecules in these devices is especially important for ensuring that the sensing functions of the OFET are effective. Generally, analysis platforms are developed by modifying the gate/electrolyte or OSC/electrolyte interface using biomolecules, such as enzymes, antibodies, or deoxyribonucleic acid (DNA) to ensure high selectivity. To provide better or more convenient biological immobilization methods for researchers in this field and thereby improve detection sensitivity, this review summarizes recent developments in the immobilization strategies used for biological macromolecules in OFETs, including cross-linking, physical adsorption, embedding, and chemical covalent binding. The influences of biomolecules on device performance are also discussed. [ABSTRACT FROM AUTHOR]