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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]

• 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]

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]

[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]

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]

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]

• 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]