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<jats:p>It is important for the electrolytes to maintain and enhance the lithium ion battery electrochemical performance, and solvation of Li<jats:sup>+</jats:sup> is a key parameter for the property of the electrolytes. The comparative study on Li<jats:sup>+</jats:sup> solvation structures, energy, enthalpy, Gibbs free energy, infrared and Raman spectra in common organic electrolyte solvents is completed by density functional theory (DFT) method. The solvation reaction energy results suggest that the Li<jats:sup>+</jats:sup> solvation priority order is propylene carbonate (PC) &gt; ethylene carbonate (EC) &gt; ethyl methyl carbonate (EMC) &gt; diethyl carbonate (DEC) &gt; tetrahydrofuran (THF) &gt; dimethyl carbonate (DMC) &gt; 1,3-dioxolane (DOL) &gt; dimethoxyethane (DME) to form 5sol-Li<jats:sup>+</jats:sup>. It is also indicated that the most innermost solvation shell compounds formations by stepwise spontaneous solvation reaction are four cyclic solvent molecules and three linear solvent molecules combining one Li<jats:sup>+</jats:sup> forming 4sol-Li<jats:sup>+</jats:sup> and 3sol-Li<jats:sup>+</jats:sup>, respectively, at room temperature. Besides, the vibration peaks for C=O and C–O bonds in carbonate ester solvents-Li<jats:sup>+</jats:sup> compounds shift to lower frequency and higher frequency, respectively, when the Li<jats:sup>+</jats:sup> concentration increases in the solvation compounds. All Li–O stretching vibration peaks shift to higher frequency until forming 2solvent-Li<jats:sup>+</jats:sup> complexes, and C–H stretching also shifts to higher frequency except for <jats:italic>n</jats:italic>DME-Li<jats:sup>+</jats:sup> solvation compounds. The Raman spectrum is more agile to characterize C–H vibrations and IR is agile to C=O, C–O, and Li–O vibrations for Li<jats:sup>+</jats:sup> solvation compounds.</jats:p>

<jats:p>Silicon is an important high capacity anode material for the next generation Li-ion batteries. The electrochemical performances of the Si anode are influenced strongly by the properties of the solid electrolyte interphase (SEI). It is well known that the addition of flouroethylene carbonate (FEC) in the carbonate electrolyte is helpful to improve the cyclic performance of the Si anode. The possible origin is suggested to relate to the modification of the SEI. However, detailed information is still absent. In this work, the structural and mechanical properties of the SEI on Si thin film anode in the ethylene-carbonate-based (EC-based) and FEC-based electrolytes at different discharging and charging states have been investigated using a scanning atomic force microscopy force spectroscopy (AFMFS) method. Single-layered, double-layered, and multi-layered SEI structures with various Young’s moduli have been visualized three dimensionally at nanoscale based on the hundreds of force curves in certain scanned area. The coverage of the SEI can be obtained quantitatively from the two-dimensional (2D) project plots. The related analysis indicates that more soft SEI layers are covered on the Si anode, and this could explain the benefits of the FEC additive.</jats:p>

<jats:p>With the need of the internet of things, big data, and artificial intelligence, creating new computing architecture is greatly desired for handling data-intensive tasks. Human brain can simultaneously process and store information, which would reduce the power consumption while improve the efficiency of computing. Therefore, the development of brain-like intelligent device and the construction of brain-like computation are important breakthroughs in the field of artificial intelligence. Memristor, as the fourth fundamental circuit element, is an ideal synaptic simulator due to its integration of storage and processing characteristics, and very similar activities and the working mechanism to synapses among neurons which are the most numerous components of the brains. In particular, memristive synaptic devices with optoelectronic responding capability have the benefits of storing and processing transmitted optical signals with wide bandwidth, ultrafast data operation speed, low power consumption, and low cross-talk, which is important for building efficient brain-like computing networks. Herein, we review recent progresses in optoelectronic memristor for neuromorphic computing, including the optoelectronic memristive materials, working principles, applications, as well as the current challenges and the future development of the optoelectronic memristor.</jats:p>

<jats:p>Nitrogen-doped TiO<jats:sub>2</jats:sub> nanotubes (TNTs) were prepared by ion implantation and anodic oxidation. The prepared samples were applied in photocatalytic (PC) oxidation of methyl blue, rhodamine B, and bisphenol A under light irradiation. To explore the influence of doped ions on the band and electronic structure of TiO<jats:sub>2</jats:sub>, computer simulations were performed using the VASP code implementing spin-polarized density functional theory (DFT). Both substitutional and interstitial nitrogen atoms were considered. The experimental and computational results propose that the electronic structure of TiO<jats:sub>2</jats:sub> was modified because of the emergence of impurity states in the band gap by introducing nitrogen into the lattice, leading to the absorption of visible light. The synergy effects of tubular structures and doped nitrogen ions were responsible for highly efficient and stable PC activities induced by visible and ultraviolet (UV) light.</jats:p>

<jats:p>Dark count is one of the inherent noise types in single-photon diodes, which may restrict the performances of detectors based on these diodes. To formulate better designs for peripheral circuits of such diodes, an accurate statistical behavioral model of dark current must be established. Research has shown that there are four main mechanisms that contribute to the dark count in single-photon avalanche diodes. However, in the existing dark count models only three models have been considered, thus leading to inaccuracies in these models. To resolve these shortcomings, the dark current caused by carrier diffusion in the neutral region is deduced by multiplying the carrier detection probability with the carrier particle current at the boundary of the depletion layer. Thus, a comprehensive dark current model is constructed by adding the dark current caused by carrier diffusion to the dark current caused by the other three mechanisms. To the best of our knowledge, this is the first dark count simulation model into which incorporated simultaneously are the thermal generation, trap-assisted tunneling, band-to-band tunneling mechanisms, and carrier diffusion in neutral regions to evaluate dark count behavior. The comparison between the measured data and the simulation results from the models shows that the proposed model is more accurate than other existing models, and the maximum of accuracy increases up to 31.48% when excess bias voltage equals 3.5 V and temperature is 50 °C.</jats:p>

<jats:p>We present a novel stackable luminescent device integrating a blue light emitting diode (LED) with a red organic LED (OLED) in series. The anode of the OLED is connected with the cathode of the LED through a via in the insulation layer on the LED. The LED–OLED hybrid device is electroluminescent and two electroluminescence (EL) peaks (the blue peak around 454 nm and the red peak around 610 nm) are observed clearly. The effect of the indium tin oxide (ITO) layer on the device performance is analyzed. Compared with the individual LED and OLED, their combination shows great potential applications in the field of white lighting, plant lighting, and display.</jats:p>

<jats:p>The intrinsic stochasticity of resistance switching process is one of the holdblocks for using memristor as a fundamental element in the next-generation nonvolatile memory. However, such a weakness can be used as an asset for generating the random bits, which is valuable in a hardware security system. In this work, a forming-free electronic bipolar Pt/Ti/Ta<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub>/Pt memristor is successfully fabricated to investigate the merits of generating random bits in such a device. The resistance switching mechanism of the fabricated device is ascribed to the electric field conducted electrons trapping/de-trapping in the deep-energy-level traps produced by the “oxygen grabbing” process. The stochasticity of the electrons trapping/de-trapping governs the random distribution of the set/reset switching voltages of the device, making a single memristor act as a random bit in which the resistance of the device represents information and the applied voltage pulse serves as the triggering signal. The physical implementation of such a random process provides a method of generating the random bits based on memristors in hardware security applications.</jats:p>

<jats:p>Thermal stability of core-shell nanoparticles (CSNPs) is crucial to their fabrication processes, chemical and physical properties, and applications. Here we systematically investigate the structural and thermal stabilities of single Au@Ag CSNPs with different sizes and their arrays by means of all-atom molecular dynamics simulations. The formation energies of all Au@Ag CSNPs we reported are all negative, indicating that Au@Ag CSNPs are energetically favorable to be formed. For Au@Ag CSNPs with the same core size, their melting points increase with increasing shell thickness. If we keep the shell thickness unchanged, the melting points increase as the core sizes increase except for the CSNP with the smallest core size and a bilayer Ag shell. The melting points of Au@Ag CSNPs show a feature of non-monotonicity with increasing core size at a fixed NP size. Further simulations on the Au@Ag CSNP arrays with 923 atoms reveal that their melting points decrease dramatically compared with single Au@Ag CSNPs. We find that the premelting processes start from the surface region for both the single NPs and their arrays.</jats:p>

<jats:p>The interaction between C<jats:sub>60</jats:sub> nanoparticles and biomembranes has been of great interest in researches over the past decades due to their novel applications as well as potential cytotoxicity. In this work, we study the deformation of the small unilamellar vesicles composed of dipalmitoylphosphatidylcholine (DPPC) lipid bilayers infiltrated with C<jats:sub>60</jats:sub> nanoparticles of different molecular concentrations through coarse-grained molecular dynamics simulations. By employing the Helfrich spontaneous curvature model, the bending modulus and the spontaneous curvature of the vesicles with C<jats:sub>60</jats:sub> nanoparticles of different concentrations are obtained according to the simulation data. The results show that the bending modulus and the spontaneous curvature of pure DPPC vesicle membranes are approximately 1.6 × 10<jats:sup>−19</jats:sup> J and 1.4 nm<jats:sup>−1</jats:sup>, respectively. Both of them increase linearly approximately as the C<jats:sub>60</jats:sub> concentration increases from 0 to 16.3%. The density profiles of vesicles, the order of lipid packing and the diffusion characteristics of DPPC and C<jats:sub>60</jats:sub> are also investigated.</jats:p>

<jats:p>The novel coronavirus pneumonia triggered by COVID-19 is now raging the whole world. As a rapid and reliable killing COVID-19 method in industry, electron beam irradiation can interact with virus molecules and destroy their activity. With the unexpected appearance and quickly spreading of the virus, it is urgently necessary to figure out the mechanism of electron beam irradiation on COVID-19. In this study, we establish a virus structure and molecule model based on the detected gene sequence of Wuhan patient, and calculate irradiated electron interaction with virus atoms via a Monte Carlo simulation that track each elastic and inelastic collision of all electrons. The characteristics of irradiation damage on COVID-19, atoms’ ionizations and electron energy losses are calculated and analyzed with regions. We simulate the different situations of incident electron energy for evaluating the influence of incident energy on virus damage. It is found that under the major protecting of an envelope protein layer, the inner RNA suffers the minimal damage. The damage for a ∼100-nm-diameter virus molecule is not always enhanced by irradiation energy monotonicity, for COVID-19, the irradiation electron energy of the strongest energy loss damage is 2 keV.</jats:p>