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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.

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]

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.

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]

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.

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.

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]

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.

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.

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.

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.

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The beam-column joints of traditional timber frames are mortise-tenon or iron hook joints, which are prone to joint damage during earthquakes, thus causing the collapse of buildings. To avoid such adverse seismic damage, this study proposes an energy-dissipation joint applied to timber frames. The energy-dissipation joints serve both as joint connections and knee braces, providing multiple lines of seismic defense. To verify the effectiveness of the energy-dissipation joints, quasi-static tests were conducted on four specimens. It is shown that the energy-dissipation joints successfully achieve the intended objective. When the inter-story drift ratio of the timber frame is small, the energy-dissipation elements in the energy-dissipation joints remain in an elastic state. As the inter-story drift ratio increases, the energy-dissipation elements in the energy-dissipation device gradually begin to yield and dissipate energy. The energy-dissipation elements cease operation when the inter-story drift ratio is relatively large, and the energy-dissipation device transforms into knee brace to provide lateral stiffness to the timber frame. Compared with the traditional timber frame, the load-bearing capacity, lateral stiffness, and energy dissipation capacity of the timber frame with the energy-dissipation joints were significantly improved, and the failure mode shifted from beam-column joint damage to timber column fracture damage, and no collapse occurred under an inter-story drift ratio of 12.86%. • Proposes an energy-dissipating joint applied to timber frames. • Energy-dissipating joint providing multiple lines of seismic defense. • Energy-dissipating device transforms into knee brace in the late stage of work. • The failure mode shifted from joint damage to timber column fracture damage. • Timber frame with energy-dissipation joints have better collapse resistance. [ABSTRACT FROM AUTHOR]

In the past years, the conformal coating on the printed circuit board has been widely used because it offers several advantages in terms of protection and reliability of electronic circuits. However, the coating is a dielectric material, which can impact on the performance of radio-frequency components such as microstrip filters. Hence, the coating characterisation from the dielectric point of view is essential in order to design filters that meet prefixed requirements. Although the dielectric properties of commercial conformal coatings are well known, specific analyses on the effect of the coating on devices performance for space applications are not present in the literature and the coating manufactures do not often provide an appropriate characterisation of dielectric properties, making the analysis and the design of the microstrip filters difficult. The authors discuss numerical and experimental results regarding the performance of a coupled microstrip filter and show that the presence of CV-1152 coating causes a significant shift of the S-parameters. Moreover, a new configuration of the filter based on a fractal shape is proposed, which is characterised by more compact size and an optimised bandwidth.

Harnessing solar energy with solar cells based on organic materials (in particular polymeric solar cells) is an attractive alternative to silicon-based solar cells due to the advantages of lower weight, flexibility, lower manufacturing costs, easier integration with other products, low environmental impact during manufacturing and operations and short energy payback times. However, even with the latest efficiencies reported up to 17%, the reproducibility of these efficiencies is not up to par, with a significant variation in the efficiencies reported across the literature. Since these devices are based on ultrathin multilayer organic films, interfaces play a major role in their operation and performance. This review gives a concise account of the major interfacial issues that are responsible for influencing the device performance, with emphasis on their physical mechanisms. After an introduction to the basic principles of polymeric solar cells, it briefly discusses charge generation and recombination occurring at the donor-acceptor bulk heterojunction interface. It then discusses interfacial morphology for the active layer and how it affects the performance and stability of these devices. Next, the formation of injection and extraction barriers and their role in the device performance is discussed. Finally, it addresses the most common approaches to change these barriers for improving the solar cell efficiency, including the use of interface dipoles. These issues are interrelated to each other and give a clear and concise understanding of the problem of the underperformance due to interfacial phenomena occurring within the device. This review not only discusses some of the implemented approaches that have been adopted in order to address these problems, but also highlights interfacial issues that are yet to be fully understood in organic solar cells.

In the past years, the conformal coating on the printed circuit board has been widely used because it offers several advantages in terms of protection and reliability of electronic circuits. However, the coating is a dielectric material, which can impact on the performance of radio-frequency components such as microstrip filters. Hence, the coating characterisation from the dielectric point of view is essential in order to design filters that meet prefixed requirements. Although the dielectric properties of commercial conformal coatings are well known, specific analyses on the effect of the coating on devices performance for space applications are not present in the literature and the coating manufactures do not often provide an appropriate characterisation of dielectric properties, making the analysis and the design of the microstrip filters difficult. The authors discuss numerical and experimental results regarding the performance of a coupled microstrip filter and show that the presence of CV-1152 coating causes a significant shift of the S-parameters. Moreover, a new configuration of the filter based on a fractal shape is proposed, which is characterised by more compact size and an optimised bandwidth. [ABSTRACT FROM AUTHOR]

For the development of aqueous hybrid capacitors, it is essential to fulfill the role of active materials and concentrate on the device's performance. However, these goals are challenging because the conventional electrodes meet a heterogeneous distribution of active materials and large-portion passive components. We develop a universal method to prepare free-standing hierarchical graphene-based composited electrodes here. Compared to conventional electrodes, this hierarchical electrode can distribute active materials effectively, improve ion diffusion, increase charge transfer, reduce parasitic reactions, decrease passive components, etc. , which facilitates fulfilling the role of active materials and increases the device performance. Typically, the hierarchical electrodes show higher capacity for Fe 3 O 4 , NiCo-LDH, PANI, and active carbon. In addition, the hierarchical electrodes can generate a high energy density of 43.7 Wh kg−1 (based on the whole electrodes instead of active materials). Also, the preparation method of hierarchical electrodes is facile, energy-saving, eco-friendly, etc. , facilitating the practical application. Such a universal preparation method and high electrochemical performance hold great potential for developing high-performance energy storage devices. • A substrate- and binder-free hierarchical electrode is developed. • The preparation is completed at 35 °C without any specific equipment. • The hierarchical electrodes fulfill the role of active materials. • An aqueous hierarchical hybrid capacitor achieves high device performance. [ABSTRACT FROM AUTHOR]

Aluminum-doped zinc oxide (AZO) is a promising substrate for perovskite solar cells (PSCs) because of its low cost, easy accessibility, and good conductivity. However, its relatively low transmittance with low resistance and inevitable reflectance loss makes it unfavorable for high-performance AZO-based PSCs. Herein, a simple and effective strategy that textures the surface of AZO substrate via a diluted HCl etching, is developed to boost PSC performance. The textured AZO substrate exhibits greater haze, higher transmittance, and lower reflectance for permitting more photons to reach and be absorbed within PSCs. In addition, the textured AZO substrate not only exhibits improved surface wettability that can enhance the buried interfacial contact and enable the growth of high-quality perovskite film, but also possesses reduced oxygen vacancies and lower work function (WF) that can suppress the recombination and reduce the energy barrier for electron extraction. As a result, the PSC on textured AZO substrate shows improved fill factor (FF, 70 %) and enhanced short-circuit current density (J sc , 23.7 mA/cm2) compared with the reference cells (63 % and 21.1 mA/cm2), yielding a much-increased power conversion efficiency (PCE) from 13.9 % to 17.6 %. The present work opens the door for the employment of AZO substrate in future commercialization of PSCs. • Surface textured AZO was used as an alternative to ITO or FTO for perovskite solar cells. • Wet-chemical etching with diluted HCl was applied for AZO surface texturing. • Textured AZO substrate exhibited high transmittance, haze, and light scattering ability. • The power conversion efficiency was increased from 13.9 % to 17.6 %. [ABSTRACT FROM AUTHOR]

The use of multilayer semiconductor heterojunction structures has shown promise in infrared detector applications. Several heterostructures with innovative compositional and architectural designs have been displayed on emerging infrared technologies. In this review, we aim to illustrate the principles of heterostructure detectors for infrared detection and explore the recent progress on the development of detectors with the split-off band and threshold wavelength extension mechanism. This review article includes an understanding of the compositional and the architectural design of split-off band detectors and to prepare a database of their performances for the wavelength extension mechanism. Preparing a unique database of the compositional or architectural design of structures, their performance, and penetrating the basics of infrared detection mechanisms can lead to significant improvements in the quality of research. The brief outlook of the fundamentals of the infrared detection technique with its appropriateness and limitations for better performance is also provided. The results of the long-term study presented in this review article would be of considerable assistance to those who are focused on the heterostructure infrared detector development.

In the periodic table of elements, boron (B, atomic number, 5) and nitrogen (N, atomic number, 7) are neighboring to the carbon (C, atomic number, 6). Thus, the total electronic number of two carbons (12) is equal to the electronic sum of one boron (5) and one nitrogen (7). Accordingly, replacing two carbons with one boron and one nitrogen in a π-conjugated structure gives an isoelectronic system, i.e., the BN perturbed π-conjugated system, comparing to their all-carbon analogs. The BN embedded π-conjugated systems have unique properties, e.g., optical absorption, emission, energy levels, bandgaps, and packing order in contrast to their all-carbon analogs and have been intensively studied in terms of novel synthesis, photophysical characterizations, and electronic applications in recent years. In this review, we try to summarize the synthesis methods, optoelectronic properties, and progress in organic photovoltaic (OPV) applications of the representative BN embedded polycyclic π-conjugated systems. Firstly, the narrative will be commenced with a general introduction to the BN units, i.e., B←N coordination bond, B-N covalent bond, and N-B←N group. Then, the representative synthesis strategies toward π-conjugated systems containing B←N coordination bond, B-N covalent bond, and N-B←N group will be summarized. Afterwards, the frontier orbital energy levels, optical absorption, packing order in solid state, charge transportation ability, and photovoltaic performances of typical BN embedded π-conjugated systems will be discussed. Finally, a prospect will be proposed on the OPV materials of BN doped π-conjugated systems, especially their potential applications to the small molecules organic solar cells.

In this paper, we report the device performance of a new graphene nanoribbon field-effect transistor (GNRFET) with a linearly graded binary metal alloy gate through a quantum simulation study. The proposed device is simulated by solving the Schrödinger equation using the mode space non-equilibrium Green’s function (NEGF) formalism coupled self-consistently with a two-dimensional Poisson equation in the ballistic limit. Comparisons are made for the I-V characteristics, subthreshold swing, voltage gain, and cut-off frequency among conventional GNRFETs and work-function-engineered gate GNRFETs. Moreover, the impact of variation in GNR channel length on device performance is also studied. We have found that the GNRFET endowed with work-function-engineered gate can improve the subthreshold swing and provide higher voltage gain and cut-off frequency than the conventional GNRFET. The obtained results indicate that the proposed device can alleviate the critical problem and further improve immunity against short channel effects of nanoscale GNRFETs for high performance analog sub-10-nm technology. [ABSTRACT FROM AUTHOR]

In this work, we have studied the effect of [6,6]-phenyl C 61 -butyric acid methyl ester (PC 61 BM) phase on the performance and charge photogeneration processes of poly (3-hexylthiophene) (P3HT) polymer solar cells (PSCs) using photoluminescence, electrochemical doping and transient absorption methods. The results show that the PC 61 BM phase facilitates the dissociation of photogenerated excitons and increases the charge photogeneration yield. The PC 61 BM phase blend in the active layer is able to increase the yield of the delocalized polarons (DP) in the P3HT donor phase using electrochemical doping methods. Furthermore, PC 61 BM phase facilitates the formation of bipolarons (BP) from polarons (P). These results aid in better understanding the charge photogeneration processes of PC 61 BM blended PSCs. [ABSTRACT FROM AUTHOR]

The process of deposition of the solid phase of a suspension in the rotor of a continuous sedimentation centrifuge with a rigid wall and periodic discharge of the sediment was investigated based on the provisions of the hydrodynamics of slow movements. Results of quantitative analysis of the process of centrifugal separation of the suspension show that the calculation method of the efficiency of this process should be improved taking into account the layered structure of the flow based on the first model. [ABSTRACT FROM AUTHOR]

Moore’s law is approaching its physical limit. Tunneling field-effect transistors (TFETs) based on 2D materials provide a possible scheme to extend Moore’s lawdown to the sub-10-nm region owing to the electrostatic integrity and absence of dangling bonds in 2D materials. We report an ab initio quantum transport study on the device performance of monolayer (ML) black phosphorene (BP)TFETs in the sub-10-nm scale (6-10 nm). Under the optimal schemes, the ML BP TFETs show excellent device performance along the armchair transport direction.The on-state current, delay time, and power dissipation of the optimal sub-10-nm ML BP TFETs significantly surpass the latest International Technology Roadmap for Semiconductors (ITRS) requirements for high-performance devices. The subthreshold swings are 56-100 mV/dec, which are much lower than those of their Schottky barrier and metal oxide semiconductor field-effect transistor counterparts. [ABSTRACT FROM AUTHOR]

Based on the postulates of the hydrodynamics of slow motion and process parameter values close to realistic values, a quantitative analysis of the process of separating a liquid water + oil system in a hydrocyclone was performed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigations on non-fused-ring acceptors with progressive evolutions. • Counterbalance between high photo-response and low energy loss. • J52:O-PC-EH-based device achieved a best efficiency of 14.43% (certified: 14.1%). Resolving competitive counterbalance between high external quantum efficiency (EQE) response and low energy loss is critical for achieving efficient organic solar cells (OSCs), including those based on low-cost non-fused-ring electron acceptor (NFREA). In this work, we performed a comparable study by utilizing four NFREAs with progressive evolutions in molecular structures, energetic levels, spectral coverages, crystallinity, etc, to pair with polymer donor J52. By regulating the terminal and side chains of NFREAs, the enhanced intramolecular charge transfer (ICT) effect allows O-PC-EH possessing the broader spectral coverage for higher photocurrent, the reduced energetic offset enables O-PC-EH-based device owning higher luminescence property for lower energy loss, the strengthened crystallinity endows O-PC-EH-based blend better charge transport property for less charge recombination. With those comprehensive managements from molecule to blend properties, the J52:O-PC-EH-based OSCs achieved the best efficiency of 14.4% (certified: 14.1%) with benefits in all the three device parameters. This work reveals the importance of fine-tuning molecular structures of NFREAs according to paired polymer donor for maximizing the device performances. [ABSTRACT FROM AUTHOR]

With the advancement of new technologies, the number of connected devices, the amount of data generated, and the need to build an intelligently connected network of things to improve and enrich the human ecosystem open new doors to modifications and adaptations of current cellular network infrastructures. While more focus is given to low power wide area (LPWA) applications and devices, a significant challenge is the definition of Internet of Things (IoT) use cases and the value generation of applications on already existing IoT devices. Smartphones and related devices are currently manufactured with a wide range of smart sensors such as accelerometers, video sensors, compasses, gyros, proximity sensors, fingerprint sensors, temperature sensors, and biometric sensors used for various purposes. Many of these sensors can be automatically expanded to monitor a user’s daily activities (e.g., fitness workouts), locations, movements, and real-time body temperatures. Mobile network operators (MNOs) play a substantial role in providing IoT communications platforms, as they manage traffic flow in the network. In this paper, we discuss the global concept of IoT and machine-type communication (MTC), and we conduct device performance analytics based on data traffic collected from a cellular network. The experiment equips service providers with a model and framework to monitor device performance in a network.