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Polypyrrole (PPy)–Ag composites have been directly deposited on a nickel foam via the redox reaction between pyrrole and silver nitrate. As a catalyst, the nickel foam was able to accelerate the redox reaction and lead to the formation of PPy–Ag composites, which shows a strong adhesive force to the substrate. The electrochemical properties of the PPy–Ag–nickel foam electrode were systematically investigated by using cyclic voltammetry, galvanostatic charge–discharge and cycle stability measurements in 0.5 M K2SO4 electrolyte. The redox performance properties, good charge–discharge stability and high specific capacitance of 493 F g−1 at a current density of 1 A g−1 demonstrated the appropriate application of the PPy–Ag–nickel foam electrode for the high energy density supercapacitors. [ABSTRACT FROM AUTHOR]

The phenomenon of resistive switching (RS) has been demonstrated in several non-magnetic and some magnetic oxide systems, however the 'magnetic' aspect of magnetic oxides has not been emphasized especially in terms of low field tunability. In our work, we examined the CoFe2O4/La0.66Sr0.34MnO3 all-magnetic oxide interface system for RS and discovered a very sharp (bipolar) transition at room temperature that can be gated with high sensitivity by low magnetic fields (∼0-100 mT). By using a number of characterizations, we show that this is an interface effect, which may open up interesting directions for manipulation of the RS phenomenon. [ABSTRACT FROM AUTHOR]

Abstract: We report on rational synthesis and optical characteristics of highly crystallined ZnO nanorods which were grown by a facile chemical vapor transport method. Temperature-dependent photoluminescence spectra of as-fabricated ZnO nanorods are dominated by near-band-edge emission with a characteristic fine structure due to high crystallinity. Furthermore, the recombination emission involving carrier dynamics of near-band-edge emission in ZnO nanorods was systematically investigated by temperature-dependent time-resolved photoluminescence spectroscopy. Recombination peaks pertaining to the exciton emissions are monitored and resolved in both temporal and spatial regimes. [Copyright &y& Elsevier]

Time resolved photoluminescence (TRPL) and transient absorption (TA) spectroscopy reveal an ultrafast charge transfer (CT) process, with an electron localization time constant 39±9 ps, between the ZnO host and the Cu dopants in Cu-doped ZnO nanowires. This CT process effectively competes with the ZnO band edge emission, resulting in the quenching of the ZnO UV emission. TRPL measurements show that the UV decay dynamics coincides with the buildup of the Cu-related green emission. TA measurements probing the state-filling of the band edge and defect states provide further support to the CT model where the bleaching dynamics concur with the TRPL lifetimes. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate the coexistence of nonvolatile memory (NVM) and volatile threshold switching (VTS) behaviors in an Ag-embedded sodium-alginate-based memristor using the current pulse mode. High and low compliance currents allow the device to present stable and reliable NVM and VTS behaviors, respectively. Specifically, NVM and VTS behaviors randomly occur under a compliance current of 40 μA. On this basis, four polygon Boolean operations (AND, OR, NOT, and XOR) and physical unclonable functions (PUFs) with an inter-class Hamming distance of 50.75% are demonstrated simultaneously in memristive devices. Adopting PUF keys, image encryption and decryption are implemented by executing the XOR logic operation. Our memristive devices have the ability of in-memory computing and providing PUFs simultaneously and thus great potential for hardware security applications. [ABSTRACT FROM AUTHOR]

Owing to the intriguing physical properties and significant spintronic applications, magnetic skyrmions have recently drawn intensive attention. Particularly, the skyrmion-based non-volatile memory (Sky-NVM) devices promise to be spintronic building blocks with high efficiency. However, tailoring Sky-NVM to achieve an energy-efficient and reliable operation in a synthetic, CMOS compatible, and magnetic-field-free integration is a challenging issue. Here, we report a new type of compact Sky-NVM with tailored skyrmion motion dynamics via in-plane strain gradient engineering. The skyrmion motion is merely driven by an in-plane electric field utilizing the magnetoelectric coupling effect, and the programmable switching is realized by gate biasing the potential barrier height via a voltage-controlled magnetic anisotropy. The proposed device is CMOS process compatible, and the comprehensive micromagnetic simulation results demonstrate that by applying a 0.3 V in-plane voltage combined with −0.17 V gate voltage, its write latency and the energy consumption reach 5.85 ns and 4.77 aJ/bit, respectively, superior to the state-of-the-art counterparts. Our work paves a new path toward ultra-low-power spintronic memory devices. [ABSTRACT FROM AUTHOR]

Spin torque nano-oscillators (STNOs) hold significant promise for communication and bio-inspired computing applications. However, their modulation capability is constrained by a dilemma between frequency window and linewidth reduction, particularly in hypercritical conditions like the presence of an external magnetic field. This poses a notable challenge in the practical application of STNOs. Here, we report a unique type of all-electrical compact STNOs that employ the tilted magnetic anisotropy (TMA), which can efficiently promote the linewidth Δf reduction and precisely modulate oscillation frequency ranging from 495 to 556 MHz. The developed STNOs consist of a ferromagnetic reference layer with tunable TMA, wherein the spin transfer torque along the tilted spin polarization direction elaborates a self-oscillation of magnetic moments in the free layer without application of magnetic field. The free layer equips in a magnetic droplet oscillation mode, and the oscillation frequency can be modulated either synergistically or independently by varying the current intensity and/or the TMA angle. Nevertheless, the TMA angle primarily governs the deformation of the magnetic droplet and the corresponding oscillation frequency and linewidth. Moreover, a unique 4 × 4 STNO array with optimized input current and TMA configuration is proposed to execute the reservoir computing hardware training based on nonlinear dynamic oscillation phase-coupling characteristics, promising a diverse synchronization map with high kernel quality and low generation rank for highly reliable pattern classification implementation. The developed STNOs possess a simple structure, nonlinearity, high frequency tunability, and compatibility with CMOS processes, enabling them a fundamental component for large-scale integration of advanced hardware in neuromorphic computing. [ABSTRACT FROM AUTHOR]

Stretchable strain sensors with high stability, high responsiveness, and low detection limit provide the broad potential for intelligent robots and electronic skin. However, developing low‐cost strain sensors with contact and non‐contact sensing modes remains a significant challenge. In this study, a flexible magnetic strain sensor based on a sandwich structure is proposed to address this challenge. The proposed structure utilizes the coordination between carbon black and Fe3O4 microparticles in the silicone rubber matrix to enhance the sensor's sensitivity to external strain and magnetic stimuli. The sensor exhibits excellent tensile properties with a strain range of up to 180%, fast response/recovery time (78 ms/65 ms), high stability, and durability after 9000 cycles. Moreover, the flexible magnetic strain sensors can detect micro‐vibration and micro‐strain signals. It can also be performed as electronic skin to precisely sense human movements. Furthermore, the newly developed sensor can accurately sense oncoming objects and bicycle riding speed/distance, and a flexible magnetic keyboard is conceived. Consequently, the dual‐modal magnetic strain sensor exhibits an excellent ability to identify contact and non‐contact states and has broad application prospects in next‐generation intelligent products. [ABSTRACT FROM AUTHOR]

Owing to programmable nonlinear dynamics, magnetic domain wall (DW)‐based devices can be configured to function as spintronic neurons, promising to execute sophisticated tasks as a human brain. Developing energy‐efficient, CMOS compatible, reliable, and tunable spintronic neurons to emulate brain‐inspired processes has been a key research goal for decades. Here, a new type of DW device is reported with biological neuron characteristics driven by the synergistic interaction between spin‐orbit torque and built‐in field (Hbuilt‐in) in magnetic tunnel junctions, enabling time‐ and energy‐efficient leaky‐integrate‐and‐fire and self‐reset neuromorphic implementations. A tilted magnetic anisotropic free layer is proposed and further executed to mitigate the DW retrograde motion by suppressing the Walker breakdown. Complementary experiments and micromagnetic co‐simulation results show that the integrating/leaking time of the developed spintronic neuron can be tuned to 12/15 ns with an integrating power consumption of 65 µW, which is 36× and 1.84× time and energy efficient than the state‐of‐the‐art alternatives, respectively. Moreover, the spatial distribution of Hbuilt‐in can be modulated by adjusting the width and compensation of the reference layer, facilitating tunable activation function generator exploration. Such architecture demonstrates great potential in both fundamental research and new trajectories of technology advancement for spintronic neuron hardware applications. [ABSTRACT FROM AUTHOR]

• Optical properties and ordering degree of InGaP were investigated by Zn doping. • Characterization of optical properties of InGaP by tmperature-dependent PL. • The ordering degree of the InGaP was calculated from the band gap at low temperature. • The study found that Zn doping leads to a decrease in the ordering degree of InGaP. In 0.49 Ga 0.51 P is highly promising due to its favorable lattice-matching properties with GaAs, making it well-suited for various device applications. This study investigated the influence of Zn doping on the ordering and optical properties of In 0.49 Ga 0.51 P grown on GaAs using metalorganic chemical vapor deposition. By precisely controlling the doping flow, the ordering degree of In 0.49 Ga 0.51 P was systematically modulated. The luminescence origin and bandgap characteristics of In 0.49 Ga 0.51 P were examined through temperature-dependent photoluminescence and Hall measurements. The findings demonstrate a noticeable peak shift, accompanied by a increase in the bandgap and a corresponding decrease in the ordering degree as the Zn concentration increases. [ABSTRACT FROM AUTHOR]

The potential of wearable devices and smart robotics stands to be greatly enhanced by the development of dual-mode sensors emulating human skin functionality. However, challenges in their realization and the mitigation of crosstalk issues from concurrent signals persist. We present a pressure-temperature-tactile sensor (PTTS) built upon a 3D porous structure and conductive nanocomposites encompassing graphene, multi-walled carbon nanotubes, silicone rubber, and polyaniline. The PTTS showcases a pressure detection range from 0 to 110 kPa, pressure sensitivity at 0.3488 kPa−1, a low-pressure detection threshold of 186 Pa, and temperature sensitivity up to 21.5 μV/K. Crucially, the PTTS effectively untangles the dual functions of pressure and temperature sensing, thus mitigating crosstalk. It achieves computer communication through Morse code, enabling efficient demonstrations of human-computer interaction. Furthermore, the sensor accurately captures human motion while concurrently gauging ambient temperature without signal interference. Our device introduces an innovative avenue for non-contact sensing and human-computer interaction across applications, underscoring its potential to revolutionize wearable devices and smart robotics, consequently impacting diverse industries. • The dual-mode tactile sensors were made by a simple dip-coating process using composite materials. • The dual-mode tactile sensor flexibly detects and decouples pressure and temperature signals independently. • Potential applications of contact and non-contact dual-mode tactile sensors are evaluated. [ABSTRACT FROM AUTHOR]

The gate oxide quality in SiC MOSFETs presents a significant challenge, particularly at temperatures exceeding 175 °C. This predicament arises from the gate oxide interface's propensity to trap or release charge carriers, compromising device ruggedness. In mainstream SiC MOSFETs, the gate oxide in the trench corner confronts the demanding task of enduring higher electric field strengths, thereby posing a substantial risk to overall device reliability. As a result, research entities are proactively involved in improving the SiC/oxide interfaces to enhance the devices' resilience against elevated E -field. This endeavor aims to maintain the favorable characteristics of the trench SiC MOSFETs, including low on-state resistance, minimal parasitic capacitance, and exceptional switching performance. Thus, the implementation of a streamlined process becomes crucial to fortify the trench corner, ultimately yielding boosted E -field immunity. In this report, our research focuses on enhancing the reliability of trench corner in SiC MOSFET devices. Specifically, we employ spacer etch technology to selectively shield the trench corner with high-K heterolayers, thereby enhancing the device's ability to withstand higher E -field strengths (59.2 % reinforcement) while mitigating the risk of hidden defects. Importantly, compared to the structure without protection, at high-K shielded layer contact angles ranging from 90 to 150°, the E -field decreases, correlated the enhanced reinforcement at larger angles. Furthermore, such technology enables higher E-fields and greater circuit capacity at the bottom of trench gate, leading to enhanced device reliability. Our studies confirm that the developed device structure exhibits simplicity, reliability, maturity, and controllability, rendering it suitable for large-scale integration applications. • The present work focuses on improving the SiC/oxide interfaces to enhance the resilience of SiC MOSFETs against elevated E-field, aiming to preserve the favorable characteristics of trench SiC MOSFETs. • The implementation of a streamlined process is crucial to fortify the trench corner and enhance E-field immunity, thereby boosting the reliability of SiC MOSFET devices. • Spacer etch technology is employed to selectively shield the trench corner with high-K heterolayers, resulting in a 59.2 % reinforcement of the device's ability to withstand higher E-field strengths while mitigating the risk of hidden defects. • The developed device structure, fortified by spacer etch technology, exhibits simplicity, reliability, maturity, and controllability, making it well-suited for large-scale integration applications. • The developed technology enables higher E-fields and greater circuit capacity at the bottom of the trench gate, leading to enhanced device reliability. [ABSTRACT FROM AUTHOR]

Highly efficient Hamming distance (HD) computations can significantly boost up modern data‐intensive algorithms. However, the traditional complementary metal–oxide–semiconductor devices configured circuits suffer from the huge power consumption with periphery complexity for HD computations. Herein, the implementation of highly reliable and energy efficient in‐memory HD computations in 1 Kb 1‐transistor‐1‐memristor (1T1M) TiN/HfOx/TaOx/TiN array chip is reported. 1T1M devices demonstrate a high on/off ratio of 50, high programming speed of 20 ns, and low energy consumption of 0.224 pJ bit−1. By modulating the 1T1M cell gate and source signal synergistically, the characteristic XOR operations of the binary information are executed in a reliable manner. Importantly, equipped with a stable low resistance state (LRS) distribution (coefficient of variation <11%), the developed 1T1M arrays can implement accurate HD computations between two 8‐bit strings and simultaneously store computing results in the memristors. The complementary studies demonstrate that the stable LRS is attributed to the TaOx built‐in compliance layer which facilitates the transistor surge current reduction during forming and SET, elaborating the significant potential for achieving reliable in‐memory HD computations. Such architecture manifests a 5‐ and 36.89‐fold enhancement of the processing latency and energy efficiency in comparison with latest reports, promoting the fan out of new in‐memory computing applications. [ABSTRACT FROM AUTHOR]

As an important class of spintronic material, ferromagneticoxidesemiconductors are characterized with both charge and spin degreesof freedom, but they often show weak magnetism and small coercivity,which limit their applications. In this work, we synthesized Nd-dopedZnO nanowire arrays which exhibit stable room temperature ferromagnetismwith a large saturation magnetic moment of 4.1 μB/Nd as well as a high coercivity of 780 Oe, indicating giant magneticanisotropy. First-principles calculations reveal that the remarkablemagnetic properties in Nd-doped ZnO nanowires can be ascribed to theintricate interplay between the spin moments and the Nd-derived orbitalmoments. Our complementary experimental and theoretical results suggestthat these magnetic oxide nanowires obtained by the bottom-up synthesisare promising as nanoscale building blocks in spintronic devices. [ABSTRACT FROM AUTHOR]

Abstract: Single-crystalline ZnO nanowires (NWs) were synthesized by a facile vapor transport method. The good orientation and high crystal quality were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscope (HRTEM) measurements. Excitation-power-dependence photoluminescence spectra of ZnO NWs show that the UV emission displayed an evident blueshift with increasing excitation power and the corresponding energy shift might be as large as 10meV. This anomalous phenomenon correlates to the band bending level caused by the surface built-in electric field due to the existence of substantial oxygen vacancies. By increasing the excitation power, the enhanced neutralization effect near the surface will reduce the built-in electric field and lead to a reduction of band bending which triggers the blueshift of the UV emission. [Copyright &y& Elsevier]

A thermal-assisted electroforming (TAE) method is proposed to address the current overshoot issue and improve the resistive switching (RS) performance of electrochemical metallization (ECM) memory with a Cu/amorphous carbon (a-C)/Pt structure. In the initial electroforming process, thermal treatment can promote the electrochemical formation of metallic conductive filament (CF). The required electroforming voltage is reduced, and the undesirable overshoot current is suppressed. As a result, the RS performance of the cell is improved, including reduced RS parameter fluctuations, enlarged off/on ratio, and enhanced cycling endurance. The cell can be operated with a low compliance current (ICC) of 50 μA, which is among the lowest value of reported a-C-based ECM memories. Benefit from the low ICC, multilevel memory with five nonvolatile resistance states in a single cell is obtained. The main role of the TAE method is interpreted as to avoid the extreme high-temperature caused by the overshoot current. Conductive-atomic force microscopy mapping implies that the suppression of overshoot current can avoid over-injection of Cu cations into the a-C layer, facilitating CF with a simple structure and low randomness. The present work offers a feasible approach for addressing the current overshoot issue and improving the performance of ECM memory. [ABSTRACT FROM AUTHOR]

High switching fluctuation induced by the random formation and rupture of conductive filaments (CFs) is a critical issue for the development of organic-inorganic perovskite-based resistive switching (RS) memory devices. In this study, a rapid microwave-annealing method is developed to reduce grain boundaries (GBs) of CH3NH3PbI3 (MAPbI3) film and improve the switching reliability of the Au/MAPbI3/FTO device. The crystal grain size of MAPbI3 is increased and the corresponding GBs number is reduced with microwave irradiation time ranging from 40 to 120 s. In the optimized case, the dispersion of the RS parameters of the Au/MAPbI3/FTO cell is greatly reduced. Specifically, the fluctuations of the high/low resistance states and SET/RESET voltages dropped from 70.4%/69.5% and 40.5%/40.3% to 20.1%/26.7% and 16.0%/11.9%, respectively. The device can be operated with reduced compliance current. These results demonstrate that reducing the number of GBs is a feasible strategy to reduce the randomness of the CFs, and thus achieve more stable RS performance in MAPbI3-based memory devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Spiking neural network, inspired by the human brain, consisting of spiking neurons and plastic synapses, is a promising solution for highly efficient data processing in neuromorphic computing. Recently, memristor-based neurons and synapses are becoming intriguing candidates to build spiking neural networks in hardware, owing to the close resemblance between their device dynamics and the biological counterparts. However, the functionalities of memristor-based neurons are currently very limited, and a hardware demonstration of fully memristor-based spiking neural networks supporting in-situ learning is very challenging. Here, a hybrid spiking neuron combining a memristor with simple digital circuits is designed and implemented in hardware to enhance neuron functions. The hybrid neuron with memristive dynamics not only realizes the basic leaky integrate-and-fire neuron function but also enables the in-situ tuning of the connected synaptic weights. Finally, a fully hardware spiking neural network with the hybrid neurons and memristive synapses is experimentally demonstrated for the first time, and in-situ Hebbian learning is achieved with this network. This work opens up a way towards the implementation of spiking neurons, supporting in-situ learning for future neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

Highly sensitive flexible three-dimensional (3D) force tactile sensors with synergistic normal and tangential force perception are urgently required for emerging electronic skin (e-skin) applications. Herein, for the first time we report a new type of capacitive 3D-force tactile sensor with high sensitivity (1.08 and 1.20 N−1 corresponding to respective normal and tangential force range of 0.7 and 0.6 N) and flexibility, rapid dynamic response (response/recovery time of ∼40/∼100 ms) and low hysteresis (5.93%) based on a U-shaped groove structure. These are developed by a low-cost, practical and efficient 3D printing technique along with a layer-by-layer assembly method. The theoretical mechanism is established to elaborate the corresponding working principle and sensing performance, which is further complementarily verified by finite element modeling (FEM). The results of theoretical calculation, FEM simulation and experimental measurements are in good agreement, consolidating the effectiveness of the developed devices as flexible 3D-force tactile sensors. Importantly, the proposed theoretical model provides constructive and general guidance for capacitive sensors. The capability of our 3D-force tactile sensor used as a flexible e-skin for tactile sensing is confirmed by gripping and slipping detection, as well as rocker movement detection. The developed flexible 3D-force tactile sensors are promising candidates for a wide range of applications, e.g. artificial skins, soft robots, intelligent prosthesis, and human–machine interface systems. [ABSTRACT FROM AUTHOR]

The nanoscale electrical and mechanical properties in the CdTe thin films solar cells were investigated using the scanning probe microscopy. The comparative localized electrical and mechanical properties between as-grown and CdCl2 treated CdTe thin films for the grain and grain boundaries were studied using the conductive atomic force microscopy (cAFM) and force modulation microscopy (FMM). An increased electrical behavior and decreased elastic stiffness in the CdCl2 treated thin films were recorded to elucidate the impact from the grain growth of CdTe grains. On applying a simulated working electrical bias into the CdTe thin-film solar cells, the electric field across the CdTe film can increase the softness of CdTe thin film. The results imply the presence of a potential mechanical failure site in the CdTe grain boundary, which may lead to device degradation. [ABSTRACT FROM AUTHOR]

To explore highly sensitive luminescent materials, a series of Er3+/Yb3+-codoped Al 2 Mo 3 O 12 microparticles were prepared through a high-temperature solid-state reaction method. The phase structure, light harvest ability, morphology, and upconversion (UC) emission characteristics of these synthesized microparticles were investigated systematically. Excited at 980 nm, glaring visible UC emissions are gained in the developed specimens, in which the optimal doping content for Yb3+ is 7 mol% and the two-photon absorption process contributes to the UC emission mechanism. Based on the fluorescence intensity ratio technology, the thermometric properties of resultant microparticles are studied by analyzing the temperature-dependent green UC emissions of Er3+ arising from the thermal coupling energy levels. The maximum absolute and relative sensitivities of final products are 0.011 K-1 and 1.09% K−1, respectively, and they are barely influenced by Yb3+ contents. Besides, via exploring the lifetimes of 2H 11/2 and 4S 3/2 levels of Er3+ at various temperatures, the relative sensitivities of resultant microparticles are determined to be 0.27% and 0.26% K−1, respectively. Furthermore, the newly developed microparticles can be adopted to fabricate fluorescent ink to realize optical anti-counterfeiting and visual temperature monitoring. Our studies demonstrate that Er3+/Yb3+-codoped Al 2 Mo 3 O 12 microparticles with strong UC emissions possess great potential for multimode visual optical thermometry applications. [Display omitted] • Excited by 980 nm, bright UC emissions are seen in the resultant samples. • Optimal doping content for Yb3+ in Al 2 Mo 3 O 12 host lattices is 7 mol%. • Based on FIR technique, S a and S r values of studied samples are 0.011 and 1.09% K−1, respectively. • Based on the temperature-dependent lifetimes, S r value of the designed compounds is 0.27% K−1. • Optical anti-fake and visual temperature monitoring are realized by using designed compounds. [ABSTRACT FROM AUTHOR]

B Spintronic Neurons b Spintronic neuron hardware explorations arouse a new surge of breakthroughs in neuromorphic computing. The developed magnetic domain wall devices demonstrate biological neuron characteristics driven by the synergistic interaction between spin-orbit torque and built-in field in magnetic tunnel junctions, facilitating a new trajectory of time- and energy-efficient leaky-integrate-fire-self-reset neurons implementation. Synergy of Spin-Orbit Torque and Built-In Field in Magnetic Tunnel Junctions with Tilted Magnetic Anisotropy: Toward Tunable and Reliable Spintronic Neurons (Adv. Sci. 30/2022). [Extracted from the article]

Progress in nanocrystal synthesis and self-assembly enables the formation of highly ordered superlattices. Recent studies focused on spherical particles with tunable attraction and polyhedral particles with anisotropic shape, and excluded volume repulsion, but the effects of shape on particle interaction are only starting to be exploited. Here we present a joint experimental-computational multiscale investigation of a class of highly faceted planar lanthanide fluoride nanocrystals (nanoplates, nanoplatelets). The nanoplates self-assemble into long-range ordered tilings at the liquid-air interface formed by a hexane wetting layer. Using Monte Carlo simulation, we demonstrate that their assembly can be understood from maximization of packing density only in a first approximation. Explaining the full phase behaviour requires an understanding of nanoplate-edge interactions, which originate from the atomic structure, as confirmed by density functional theory calculations. Despite the apparent simplicity in particle geometry, the combination of shape-induced entropic and edge-specific energetic effects directs the formation and stabilization of unconventional long-range ordered assemblies not attainable otherwise. [ABSTRACT FROM AUTHOR]

Abstract: We report a systematic study on modulating optical properties in gallium antimonide (GaSb) with the sulfur surface passivation. Compared with the pristine sample, the intensity of the photoluminescence (PL) emission from the passivated GaSb was dramatically enhanced about 15 times at room temperature. The temperature-dependent surface states were further investigated via the low temperature PL spectroscopy. The bound-edge-related transition emission (BE4) at 795meV and the residual acceptor associated emission located at 777meV were identified clearly at 10K. The observed passivation effects on the photoluminescence characteristics evolution of GaSb are discussed in detail. [Copyright &y& Elsevier]

Abstract: ZnO nanowires were grown on Au-coated Si (100) substrates by the method of vapor–liquid–solid (VLS) growth processing technique. The effects of supply time of Ar gas current on morphology and microstructure of Au-catalyzed ZnO nanowires were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. The results showed that the morphologies of ZnO nanostructures strongly depended on the time of flowing Ar gas. When the time of flowing Ar gas was 90s, ZnO showed nanowires with hexagonal structure. Their diameters and lengths were 160nm and 20μm, respectively, on average, and the Raman scattering peak located at 438cm−1 reached maximum intensity. The results also showed that the ZnO growth could be patterned by controlling the initial position of Au-coated area on the Si substrates. [Copyright &y& Elsevier]

• Heat treatment interval of Fe 80 Zr 9 B 10 Cu 1 alloy is as high as 154.7 K. • Composition, microstructure and magnetic properties correlation is revealed and elaborated. • Composition impacts on crystallizations of FeZrB and FeZrBCu alloys are established. • Thermal stability of H c in FeZrBCu alloys is developed with composition and annealing engineering. Amorphous alloy ribbons of FeZrB and FeZrBCu (1 at.% Cu) are synthesized and annealed in vacuum. Synergistic effects of the addition of Cu, and different proportions of Fe, Zr and B, on both crystallization and magnetic property of FeZrB alloys, are systematically investigated. The addition of Cu results in a lower thermal stability of FeZrBCu alloys compared to FeZrB alloys, while the heat treatment interval of FeZrBCu alloys is wider. The crystallizations of FeZrB alloys differ from each other; in contrast, those of FeZrBCu alloys are similar. The coercivity (H c) is large for FeZrB alloys in general, but small for FeZrBCu alloys at the initial annealing stage due to the nanocrystalline structure in the two-phases and the fine α -Fe nanocrystals. All developed FeZrBCu alloys demonstrate low values of H c and excellent thermal stability of H c below 898 K. The correlated mechanisms linking crystallization and magnetic characteristics are discussed in detail. [ABSTRACT FROM AUTHOR]

A reproducible p-type P-N codoped ZnO [ZnO:(P, N)] film with high quality was achieved by magnetron sputtering and post-annealing techniques. It has room-temperature resistivity of 3.98 Ωcm, Hall mobility of 1.35 cm2/Vs, and carrier concentration of 1.16 × 1018 cm-3, which is better than electrical properties of the p-type N-doped ZnO (ZnO:N) and p-type P-doped ZnO (ZnO:P) films. Additionally, the p-ZnO:(P, N)/n-ZnO homojunction showed a clear p-n diode characteristic. The p-type conductivity of ZnO:(P, N) is attributed to the formation of an impurity band above the valance band maximum, resulting in a reduction in the band gap and a decrease in the ionization energy of the acceptor, as well as an improvement in the conductivity and stability of the p-type ZnO:(P, N). [ABSTRACT FROM AUTHOR]

• The nanoreactor is obtained by the microwave-assisted surface imprinting technique. • Heterojunction formed between PEDOT and CdS improves the photocatalytic activity. • Fe 3 O 4 transfers photogenerated e- and further enhances the photocatalytic activity. • Imprinted cavity specifically adsorbs DM and improves the selectivity of nanoreactor. • PEDOT imprinted layer inhibites CdS photocorrosion and its secondary pollution. Magnetic imprinted PEDOT/CdS heterojunction photocatalytic nanoreactors are synergistically synthesized by the microwave-assisted surface imprinting technique. The coating of the PEDOT imprinted layer is conducive to the three-dimensional (3D) specific recognition and selective photocatalysis of danofloxacin mesylate due to the formation of imprinted cavities. The representative specific degradation selectivity coefficient of the developed nanoreactor relative to CdS/Fe 3 O 4 /HNT and magnetic non-imprinted PEDOT/CdS heterojunction is 2.08 and 2.11, respectively, clearly elaborating the excellent selectivity. The introduction of Fe 3 O 4 into PEDOT/CdS heterojunction enhances the transfer of photoexcited electrons, thereby, the photocatalytic activity has been significantly boosted up to ∼84.84 %. Meanwhile, the existence of PEDOT imprinted layer not only extracts the photoinduced holes produced by CdS, but also encapsulates CdS, which effectively inhibits the CdS photocorrosion and hinders its secondary pollution. With the improved selectivity and photocatalytic activity, our work paves the way to efficiently remove the target pollutant aiming at the practical application requirements. [ABSTRACT FROM AUTHOR]

Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors with blue and green emissions were synthesized by a solid-state reaction route in a reduction atmosphere. The obtained crystal structure and photoluminescent properties indicated that three various Ba2+ ions sites were partially occupied by the Eu2+ ions. The optimal doping content for Eu2+ ions in the Ba 5 SiO 4 Cl 6 system was 5 mol%. The electric dipole-dipole interaction was attributed to the involved concentration quenching effect. The thermal resistance performance was identified by using the temperature-dependent emission spectra. Importantly, the internal quantum efficiency of the established final products reached up to 50.8%. Through utilizing the diverse sensitivities of blue and green emissions from Eu2+ ions to the temperature, a neoteric optical thermometer with a high absolute and relative sensor sensitivity of 0.031 K-1 and 0.87% K−1, respectively, at 498 K was achieved. By integrating the resultant cyan phosphors, commercial CaAlSiN 3 :Eu2+ red phosphors and a near-ultraviolet chip, the warm white light-emitting diodes with admirable colorific properties were integrated and manufactured. The complementary results elaborate that the Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors are bifunctional platforms for both optical thermometer and indoor illumination. • The resultant phosphors exhibited visible cyan emission when excited at 397 nm. • The dipole-dipole interaction contributed to the concentration quenching mechanism. • The resultant phosphors possessed good thermal stability and high quantum efficiency. • The Sa and Sr values of the products was 0.031 K−1 and. • The LED lamp emitted brightness white light with superior photoelectric properties. [ABSTRACT FROM AUTHOR]