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The reliability of nanoscale electronic systems is important in various applications. However, they are becoming increasingly vulnerable to atmospheric neutrons. This research conducted spallation neutron irradiations on a Xilinx Zynq-7000 system on a chip using the China Spallation Neutron Source. The results were analyzed in combination with a Monte Carlo simulation to explore the impact of atmospheric neutrons on the single event effects of the target system on chip. Meanwhile, the contribution of thermal neutrons to the chip’s single event effect susceptibility was also assessed. It was found that absorbing thermal neutrons with a 2 mm Cd sheet can protect against the single event effect on the system on the chip by about 44.4%. The effects of B and Hf elements, inside the device, on a single event effect of the Xilinx Zynq-7000 system on chip were evaluated too. Additionally, it was discovered that 10B interacting with thermal neutrons was the primary cause of the thermal neutron-induced single event effect in the system on chip. Although Hf has a high neutron capture cross section, its presence does not significantly affect the sensitivity to single event effects. However, during atmospheric neutron irradiation, the presence of Hf increases the possibility of depositing the total dose in the tested chip.

A three-dimensional (3D) electrode was successfully fabricated by coating carbon felt substrate with PbO2 using an electrodeposition method. Compared with the conventional planar Ti/SnO2-Sb/PbO2 electrode, the CF/PbO2 electrode displayed superior electrocatalytic performance for the degradation of phenol, with an 11.2 times higher rate constant. The improved performance was due to its larger active surface area, enrichment of phenol on the surface due to adsorption, and enhanced mass transfer with the porous 3D structure. It also exhibited an 11.4 times higher current efficiency and a 9.1 times lower energy consumption due to the superior electrocatalytic activity and a higher oxidation potential to hinder oxygen evolution. Moreover, the generation rate of •OH from CF/PbO2 was 1.3 times higher than that of the Ti/SnO2-Sb/PbO2 electrode. The surface chemistry on the CF/PbO2 electrode during phenol degradation was explored by in situ attenuated total reflection-Fourier transform infrared (ATR-FTIR) characterization, with aromatic intermediates and carboxylic acids identified as key reaction intermediates. This composite electrode also presented excellent long-term stability and durability and negligible leaching of Pb cation, demonstrating as a promising electrode for the electrocatalytic degradation of refractory pollution in wastewater treatment.

CoO/NiO nanosheet assembled nanocages (CoO/NiO@C-NC) were prepared to improve the electrochemical performance of Li–S batteries. CoO/NiO@C-NC shows a synergistic adsorption–electrocatalysis effect to accelerate the redox of lithium polysulfides.

Developing efficient catalysts with low cost and environmental friendliness for peroxymonosulfate (PMS) activation attracts broad interest. In this study, TiO

The narrow acid pH range and the nonselectivity of the dominant •OH limit the Fenton systems to remediate the organic wastewater. Inspired by the role of heme in physiological processes, we employed iron porphyrin as a novel homogeneous catalyst to address this issue. Multiple active species are identified during the activation of H

Hemin has attracted considerable interest as an efficient catalyst recently, however, its direct application is inefficient due to severe molecular aggregation. Immobilizing hemin on various supports is a feasible approach to address this issue. In this work, a CNTs-hemin catalyst was prepared by loading hemin onto multiwalled carbon nanotubes (CNTs) through ball milling. Compared with hemin, CNTs-hemin demonstrates remarkably enhanced performance in the peroxymonosulfate system, with a 650-fold improvement of apparent rate constant, reaching 97.8% degradation of sulfathiazole in 5 min. High-valent iron-oxo porphyrin cation ((Porp)

Power overshoot that presents in the power curves of microbial fuel cells (MFCs) is one of the main reasons for the deterioration of MFC performance over the high current region. In this research, the mechanisms of power overshoot were investigated with single-chamber MFCs integrated with carbon cloth anode and Fe/N-doped carbon cathodes possessing varied capacitance properties. It was revealed that insufficient anodic current produced at high potential is responsible for power overshoot generation, which could be eliminated with higher capacitive cathode (7.79 F) compared with the one with lower capacitive cathode (3.74 F). This elimination can be ascribed to the improvement of MFC capacitance induced by cathode capacitance, which was proved by MFC charge-discharge test. However, cathode capacitance can only increase the MFC capacitance to a limited extent, as power overshoot can still occur when applying long stabilization time for polarization test.

SiOx has aroused great attention as a lithium-ion battery anode material owing to its lower cost and smaller volume expansion than Si. Nevertheless, its practical application is hindered by the still existing volume expansion and low electrical conductivity, resulting in rapid capacity decay. Herein, SiOx/C@N-doped carbon yolk@shell microspheres (denoted as YS-SiOx/C@C) have been constructed by a polydopamine-mediated selective etching strategy. In the constructed material, a SiOx/C composite core is encapsulated in a N-doped hollow carbon sphere with sufficient void space existing between the SiOx/C core and carbon shell. The yolk@shell structure could buffer the large volume fluctuation, resulting in significantly enhanced structural stability. Benefiting from the structural merits, the new composite delivers a stable high capacity of 804 mA h g−1 at 100 mA g−1 and long-term cyclability (1000 cycles at 500 mA g−1). Besides, the HF-free polydopamine-mediated selective etching strategy developed here paves a new way to construct yolk@shell structures for electrode materials.

A facile, environmentally friendly and scalable method was reported to synthesize highly dispersed Bi-BiOCl nanoparticles dispersed on three dimensional porous networks of carbon nanosheet using NaCl as template and citric acid as carbon source. The novel 3D architecture demonstrated easily accessible porous structure, large surface area, superior electrical conductivity and good mechanical flexibility, which was capable of accelerating three dimensional diffusion of ions and transport of electrons in the whole electrode. In addition, the highly dispersed Bi-BiOCl nanoparticles on the carbon backbone could facilitate the utilization of these active materials in electrochemical sensing. Under optimized conditions, Bi-BiOCl@C-3 modified glassy carbon electrode exhibited preeminent electroanalytical performance for the simultaneous sensing of Pb2+ and Cd2+ in the linear range of 1–60 μg L−1, with sensitivities of 0.38 and 0.49 μA L μg−1, respectively. The developed protocol has shown limits of detection (S/N = 3) of 0.2 and 0.4 μg L−1 for Pb2+ and Cd2+, respectively, which complies with the limits set by the World Health Organization (WHO). Moreover, high resistance to interference, long-term stability, good reproducibility and satisfactory testing recoveries were realized for real water sample, suggesting that the proposed 3D Bi-BiOCl@C-3 nanocomposite could be utilized as a promising candidate for the fabrication of high-performance electrochemical sensor.

How to exert the value-added superiority was a key link in the development of biomass valorization that heightens an appeal for a waste-minimized protocol. The fractional use of three building blocks in biomass became an urgent challenge to be faced. Herein, we report an autohydrolysis-aided biorefinery for the sequential conversion of wheat straw hemicelluloses, cellulose and lignin into xylooligosaccharides (XOS), fermentable glucose and lithium-sulfur cathode at the end of the process, respectively. The yield of XOS (DP of 2–6) reached up to 24.06% (w/w) of xylan and 6.19% (w/w) of the initial biomass. The hydrothermal treatment removed the amorphous portion and disrupted the rigid structure, thereby improving the cellulose digestibility from 14.1 to 88.9%. The molecular weights, functional groups and structural features of residual lignin after enzymatic hydrolysis were thoroughly explored for the cathode of lithium-sulfur batteries via the carbonizing process. Because of the considerable surface area, the covalent linkage between the lignin-derived carbon (LC) and sulfur, and the uniform dispersion of sulfur particles, the developed LC@S cathode exhibited excellent rate capability, and the specific capacity of 1238, 1085 and 1035 mA h g−1 at 0.1, 0.2 and 0.5 C, respectively. The LC@S cathode retained 596 mA h g−1 after 200 cycles at 0.5 C with a coulombic efficiency of 92%. The present study provides a systematic strategy that bears the primary responsibility for exploiting biomass into a potential feedstock with worthwhile functions in the thriving domains of chemicals, biofuels and energy storage devices.

Silicon photonics is considered to be an ideal solution as optical interconnect in radiation environments. Our previous study has demonstrated experimentally that radiation responses of device are related to waveguide size, and devices with thick top silicon waveguide layers are expected to be less sensitive to irradiation. Here, we design radiation-resistant arrayed waveguide gratings and Mach-Zehnder interferometers based on silicon-on-insulator with 3 µm-thick silicon optical waveguide platform. The devices are exposed to 60Co γ-ray irradiation up to 41 Mrad(Si) and 170-keV proton irradiation with total fluences from 1×1013 to 1×1016 p/cm2 to evaluate performance after irradiation. The results show that these devices can function well and have potential application in harsh radiation environments.

A hybrid electrochemical conditioning strategy for enhanced sewage sludge dewatering was proposed. A water content of 47.2 wt.% for the dewatered sludge cake was achieved at an applied voltage of 20 V for 30 min, which was significantly lower than previously reported results. The capillary suction time (CST) and specific resistance to filtration (SRF) were decreased by 75.6% and 90.9%, respectively. Four simultaneous processes, including electrooxidation, the electro-Fenton process, molecular oxygen activation via zero valent iron (ZVI) and Fe(III) flocculation, had synergetic effects on the degradation of extracellular polymeric substances (EPS) to enhance sludge dewaterability. The in situ generation of ZVI on the cathode electrode facilitated the reduction of Fe(III) to Fe(II) via activation of molecular oxygen. The sludge pH decreased spontaneously and remained acidic due to the competitive reaction of ZVI generation to hydrogen evolution as well as the Fe(III) flocculation process, which further guaranteed the high efficiency of hydroxyl radical generation. Changes in the physiochemical properties of the sludge (particle size distribution, zeta potential, viscosity and EPS characteristics) induced by the hybrid conditioning process were further explored. In addition, the economic potential of the hybrid system was preliminarily assessed (USD$ 127.6/ton dry sludge).

In this work, the radiation responses of silicon photonic passive devices built in silicon-on-insulator (SOI) technology are investigated through high energy neutron and 60Co γ-ray irradiation. The wavelengths of both micro-ring resonators (MRRs) and Mach-Zehnder interferometers (MZIs) exhibit blue shifts after high-energy neutron irradiation to a fluence of 1×1012 n/cm2; the blue shift is smaller in MZI devices than in MRRs due to different waveguide widths. Devices with SiO2 upper cladding layer show strong tolerance to irradiation. Neutron irradiation leads to slight changes in the crystal symmetry in the Si cores of the optical devices and accelerated oxidization for devices without SiO2 cladding. A 2-µm top cladding of SiO2 layer significantly improves the radiation tolerance of these passive photonic devices.

Optical properties of Mach-Zehnder interferometer and Arrayed Waveguide Grating under 60Co γ-ray and proton irradiation are investigated. Wavelength of MZI blueshifts, and the shift increases with the increasing dose due to an effective refractive index change of 10-4.

A hybrid sludge conditioning strategy with electrooxidation and Fe(II) addition was used for heavy metal removal from sewage sludge and industrial sludge, with simultaneous sludge dewatering and stabilization. With the addition of 82 mg/g DS Fe(II) and treatment time of 4.5 h, heavy metal removals of 72.95% and 78.49% for Cu, 66.29% and 84.26% for Zn, and 36.52% and 36.99% for Pb were achieved from sewage sludge and industrial sludge samples respectively. The system pH decreased to 2.33 and 2.98 and the oxidation–reduction potential (ORP) values increased to 435.90 mV and 480.60 mV in sewage sludge and industrial sludge samples, respectively, which was conducive to the desorption and dissolution of heavy metals from sludge structures and the degradation of the organic compounds that complexed with heavy metals. In addition, the hybrid conditioning process demonstrated excellent dewatering performance due to the efficient electrochemical disintegration of sludge flocs together with the coagulation of sludge particles by Fe(III) generated via electrooxidation. The strong acidic and oxidative environment produced by the enhanced electrooxidation process was also responsible for pathogen inactivation.

We present the design of an adiabatic taper coupled Ge

A delaminated MXene-bismuth (Bi@d-Ti3C2) nanocomposite was synthesized for the construction of a microgrid electrochemical sensor via mechanical milling. The Bi@d-Ti3C2 nanocomposite was synthesized by accumulation of Bi(III) on the surface of delaminated Ti3C2 nanosheets through electrostatic attraction and subsequent in-situ growth of bismuth nanorods. Under optimized experimental conditions, the sensor exhibits (a) linear responses to Pb(II), Cd(II) and Zn(II) in the concentration range from 1 to 20 μg L−1, (b) well separated peak potentials at −0.54 V, −0.76 V and − 1.15 V vs. Ag/AgCl, (c) sensitivities of 0.98, 0.84 and 0.60 μA L μg−1, and (d) detection limits of 0.2, 0.4 and 0.5 μg L−1, respectively. This performance is attributed to the uniform dispersion of Bi nanorods on electrically conductive delaminated Ti3C2 MXene, and to the enhanced diffusion due to the microgrid structure.

NiMn layered double hydroxide (NiMn LDH) and NiMn LDH/reduced graphene oxide (rGO) with flower-like 3D composite were synthesized by a simple solvothermal process. The electrochemical properties of NiMn LDH/rGO composite with different contents of rGO were studied, resulting in enhanced capacitance due to the incorporation of rGO compared with pristine NiMn LDH. The NiMn LDH/rGO composite containing 4.46 wt% rGO (LDH/rGO-4) exhibited the highest specific capacitance of 1500 F g −1 at 1 A g −1 with an excellent cyclic stability of 90.5% over 5000 charging and discharging cycles at 20 A g −1 . The asymmetric supercapacitor assembled with LDH/rGO-4 and rGO electrodes exhibited a high specific capacitance of 82.5 F g −1 at 0.5 A g −1 and superior energy density of 29.3 Wh kg −1 . These results illustrate that the LDH/rGO-4 composite is a promising material for supercapacitor applications.

In this work, a hierarchical Ni3S2@MoS2 hybrid structure was synthesized by an effective strategy with a combined hydrothermal route and subsequent annealing treatment. When tested as supercapacitor electrodes, the Ni3S2@MoS2 composites exhibited high specific capacitance of 1418.5 F g−1 at 0.5 A g−1, which also showed a good capacitance retention of 75.8% at 5 A g−1 after 1250 cycles. The Ni3S2@MoS2 composites demonstrated 1.9 fold higher specific capacitance compared to the amorphous shell counterpart (NixSy@MoS2). Furthermore, the assembled asymmetric supercapacitor (Ni3S2@MoS2//rGO) also demonstrated a capacitance of 61 F g−1 at 0.5 A g−1, with energy and power densities of 21.7 Wh kg−1 at 400 W kg−1 and 12 Wh kg−1 at 2400 W kg−1 under an operating window of 1.6 V. The asymmetric supercapacitor also showed a favorable cycle stability with 72% capacity retention over 4000 cycles at 10 A g−1. The improved electrochemical performance is attributed to the synergetic effect of the large accessible surface area and optimal contacts between the MoS2 and the electrolyte, as well as high capacitance of the metallic Ni3S2 core.

Micro-spectroscopy is a critical instrument for spectrum analysis in various applications such as chemical and biological analysis, environment detection, and hyperspectral imaging. However, current micro-spectral technique requires bulky and costly spectrometer. In this report, a new type of Bloch surface wave (BSW) based micro-spectrometer is proposed. A single silicon nanoparticle sitting on a dielectric multilayer substrate is used to excite the BSW which acts as a nanoscale unknown source. Taking advantage of the dispersion relations of BSWs, an abundant spectrally related database is formed that is useful for spectrum retrieval applications. Back-focal plane images are used to monitor the change of angular spectrum corresponding to the dispersion relationship of Bloch surface waves. Combined with an iterative algorithm, experimental retrieval of visible-range monochromatic and broadband light spectrums can be obtained. The resolution of the spectrometers can reach 2 nm across a wavelength range of 130 nm. The method in this work is CMOS compatible, enabling spectra retrieval for nanoscale radiators and can also be used to measure and retrieve the microscopic spectrum signal rapidly and timely without conventional scanning monochromator spectrometer.

The migration of long chain soluble lithium polysulfides through the separator to the anode, the so called “shuttle effect”, is one of the major issues responsible for the capacity degradation of lithium-sulfur (Li-S) batteries. In this work, N and S co-doped mesoporous carbon was prepared by a novel egg shell template method and utilized to modify the separator for high performance Li-S batteries. The discharge capacity of the second cycle retained at 1467 mAh g −1 at 1 C after 200 cycles and decayed at 0.20% per charge-discharge cycle, and a reversible capacity of 561 mAh g −1 was achieved even at 5 C rate after 200 cycles. The prepared material showed a porous hollow sphere morphology with larger surface area and N and S co-doped that can provide great electrochemical property as well as surface chemistry for the adsorption of the intermediate polysulfides. After separator modification, XPS analysis revealed that pyrrolic-type N, pyridinic-like N, and thiosulphate were the major factors contributing to the superior electrochemical performance of the CS/S cathode. This work also provided a rational design strategy for the modification of separator to effectively utilize the active sulfur and to retard the migration of dissolved polysulfides, which enhanced the performance of high energy density Li-S batteries with long cycling life.

Phase-controlled solvothermal synthesis has been proposed for the synthesis of nickel sulfide of single phase including α-NiS, Ni3S4 and NiS2 by tuning the reaction time and the addition of surfactant. The phase evolution of nickel sulfide proceeds with the increase of sulfur stoichiometry with longer reaction time in the presence of surfactant. With the addition of hexadecyl-trimethyl-ammonium bromide (CTAB), a higher sulfur stoichiometry NiS2 phase with hollow sphere geometry was synthesized at 9 h, a much shorter time due to the enrichment of S2− on CTAB micelle surface, followed by the transformation to single phase Ni3S4 finally due to dissipation of enriched sulfur to the bulk solution. The application of these three single phase materials in supercapacitors was investigated. The α-NiS electrode material outperformed the Ni3S4 and NiS2 electrodes, exhibiting a much higher specific capacitance of 800 F g−1 at 0.5 A g−1, attributable to the small particle size, high electrical conductivity and the unique hexagonal crystal structure.

Mesoporous lamellar carbon was produced by direct high temperature carbonization of bagasse, a novel process designed with affordable cost and ease of production for scale-up manufacturing. The lamellar carbon exhibited a highly mesoporous structure with favorable pore size distribution, large surface area and good electrical conductivity derived from the intrinsic thin-walled parenchyma cells of bagasse. The produced lithium–sulfur battery exhibited excellent cycle stability, due to the unique pore structure of bagasse that can accommodate the drastic volume change during battery cycling, and good rate performance, due to the high electrical conductivity of bagasse derived carbon after pyrolysis. A high initial reversible capacity of 1202 mA h g−1 (S) at 0.1C as well as a reversible capacity of 494 mA h g−1 (S) after 180 cycles at 1C was achieved, and the capacity retention was also found to be more than 70% at 1C. The designed processing method for the facile production of lamellar mesoporous carbon derived from direct carbonization of bagasse should be a feasible method for the mass production of cathode materials for high performance lithium–sulfur batteries.

The interaction between lithium polysulfides and doped heteroatoms could prevent the loss of soluble polysulfides in the cathode and mitigate the shuttle effect in lithium–sulfur batteries. Herein, a facile synthesis of mesoporous graphene platelets (NSGs) with in situ nitrogen and sulfur doping by the pyrolysis of a self-assembled L-cysteine precursor on sodium chloride crystal surface for structure-directing is presented. The mesoporous lamellar structure of the NSG possesses a uniform distribution of pyrrolic N, pyridinic N, and thiosulphate structured heteroatoms originating from in situ doping, which promotes the confinement of intermediate polysulfides. Combining the strong interactions with soluble polysulfide, flexible mesoporous architecture, and high conductivity of graphene, the prepared NSG material exhibited a high initial capacity of 1433 mA h g−1 at a 2C rate as well as a reversible capacity of 684 mA h g−1 after 200 cycles. This demonstrates that the in situ nitrogen and sulfur doped thin lamellar structure of graphene would be a promising cathode material for high performance lithium–sulfur batteries.