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Chiral-induced-spin-selectivity of electron transport and its interplay with DNA's mechanical motion are explored in a double stranded DNA helix with spin–orbit-coupling. The mechanical degree of freedom is treated as a stochastic classical variable experiencing fluctuations and dissipation induced by the environment as well as force exerted by nonequilibrium, current-carrying electrons. Electronic degrees of freedom are described quantum mechanically using nonequilibrium Green's functions. Nonequilibrium Green's functions are computed along the trajectory for the classical variable taking into account dynamical, velocity dependent corrections. This mixed quantum-classical approach enables calculations of time-dependent spin-resolved currents. We showed that the electronic force may significantly modify the classical potential, which, at sufficient voltage, creates a bistable potential with a considerable effect on electronic transport. The DNA's mechanical motion has a profound effect on spin transport; it results in chiral-induced spin selectivity, increasing spin polarization of the current by 9% and also resulting in temperature-dependent current voltage characteristics. We demonstrate that the current noise measurement provides an accessible experimental means to monitor the emergence of mechanical instability in DNA motion. The spin resolved current noise also provides important dynamical information about the interplay between vibrational and spin degrees of freedom in DNA. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries hold great promise as energy storage systems, but the shuttle effect of lithium polysulfides (LiPS) and large volume variation limit their capacity and cycle life. We have developed CoFe alloy wrapped in N-doped porous carbon spheres (e-CF@NC) with a core–shell structure through simple copolymerization and pyrolysis. The nitrogen-doped porous carbon shell provides electron and ion transport channels and more active sites for electrolyte ion adsorption. The high chemically stable carbon can limit the segregation of polysulfides, further improving the battery cycling stability. Besides, the inside CoFe alloy particles catalyze the conversion between LiPS and Li2S, speeding up reaction kinetics and reducing solvation of active sites. Consequently, lithium–sulfur batteries with e-CF@NC-2 as the cathode display a high initial specific capacity of 1146 mA h g−1 at 0.1 C, excellent rate performance (891 mA h g−1 at 1 C, 741 mA h g−1 at 2 C), and satisfied cycle stability (average capacity decay rate of 0.033% per cycle at 1 C for 300 cycles), demonstrating significant application potential. [ABSTRACT FROM AUTHOR]

MoS2 can be used for piezoresistive sensors because of its excellent mechanical and electrical properties. Herein, MoS2 nanoparticles with sulfur vacancies synergistically coupled with grain clusters to boost piezoresistive properties are fabricated. Moreover, we have demonstrated that they can be regulated efficiently for gauge factor (GF) from 2.97 to 9.99. In particular, the MoS2 nanoparticles with sulfur vacancies of 31.8% and grain cluster of 29.6 nm at the annealing temperature of 500 °C are compatible with synergistic optimization. The abundant sulfur vacancies provide many free electrons as carriers, benefiting the electron transport capability, and the conductive channels formed by the larger grain clusters endow structural stability and significant piezoresistive properties of the nanoparticles. This work demonstrates the promise of MoS2 nanoparticles as novel piezoresistive advanced materials. [ABSTRACT FROM AUTHOR]

Granular metals (GMs), consisting of metal nanoparticles separated by an insulating matrix, frequently serve as a platform for fundamental electron transport studies. However, few technologically mature devices incorporating GMs have been realized, in large part because intrinsic defects (e.g., electron trapping sites and metal/insulator interfacial defects) frequently impede electron transport, particularly in GMs that do not contain noble metals. Here, we demonstrate that such defects can be minimized in molybdenum–silicon nitride (Mo–SiNx) GMs via optimization of the sputter deposition atmosphere. For Mo–SiNx GMs deposited in a mixed Ar/N2 environment, x-ray photoemission spectroscopy shows a 40%–60% reduction of interfacial Mo-silicide defects compared to Mo–SiNx GMs sputtered in a pure Ar environment. Electron transport measurements confirm the reduced defect density; the dc conductivity improved (decreased) by 104–105 and the activation energy for variable-range hopping increased 10×. Since GMs are disordered materials, the GM nanostructure should, theoretically, support a universal power law (UPL) response; in practice, that response is generally overwhelmed by resistive (defective) transport. Here, the defect-minimized Mo–SiNx GMs display a superlinear UPL response, which we quantify as the ratio of the conductivity at 1 MHz to that at dc, Δ σ ω. Remarkably, these GMs display a Δ σ ω up to 107, a three-orders-of-magnitude improved response than previously reported for GMs. By enabling high-performance electric transport with a non-noble metal GM, this work represents an important step toward both new fundamental UPL research and scalable, mature GM device applications. [ABSTRACT FROM AUTHOR]

2D Janus Rashba semiconductors, which break both the mirror symmetry in the crystal structure and the spin degeneracy in the energy band, provide a promising platform to optimize thermoelectric performance. Herein, we use first-principles and Boltzmann transport theory to investigate the electron and phonon transport properties for Janus semiconductors of monolayer Si2AsSb and Si2SbBi. The strong Rashba spin-splitting is found in both Janus monolayers especially for Si2SbBi, which decreases the bandgaps and makes the valence bands more dispersive, resulting in decreased p-type Seebeck coefficient and increased p-type electrical conductivity. The lattice thermal conductivities of both monolayers are not low due to the weak phonon anharmonicity, strong chemical bonding, and long phonon relaxation time. The low lattice thermal conductivity of Si2SbBi than Si2AsSb mainly originates from the low phonon group velocity. Both monolayers exhibit better thermoelectric performance in n-type than in p-type. The competition among Seebeck coefficient, electrical conductivity, and electronic thermal conductivity makes the difference of optimal thermoelectric figure of merits in n-type without and with Rashba spin–orbit coupling slight for Si2AsSb, but it is significant for Si2SbBi. Within Rashba spin–orbit coupling, the optimal figure of merits at 700 K reach 0.65 and 0.59 for Si2AsSb and Si2SbBi, respectively, which indicate the potential thermoelectric applications, and will stimulate the broad study on thermoelectric properties of 2D Janus Rashba semiconductors. [ABSTRACT FROM AUTHOR]

The structural parameters, electron localization functions, electron paramagnetic resonance (EPR) parameters, formation energies, and thermodynamic transition levels of various oxygen vacancy defects in amorphous silica are comprehensively and integrally investigated by using density functional theory. The trends of changes in the oxygen vacancy defect structure and electron localization induced by the increase in distance between defective silicon atoms are clearly identified. It is shown that the dimer configuration may be the potential structure of the E δ ′ center. For the back-projected unpuckered configuration and the puckered configuration, whose EPR parameters are more consistent with the experimental values of the E γ ′ center, the unpaired electron localized on the sp3 hybridized silicon atom is a common feature. Due to the three-coordinated oxygen atom in the forward-oriented configuration, the EPR parameters are closest to those of the E α ′ center. Transformations of oxygen vacancy defects under different charge states are studied by sequentially adding and removing electrons. The thermodynamic transition level analysis reveals that the dimer and forward configurations may behave as deep traps for electron accumulation. The back-projected puckered fourfold-coordinated and fivefold-coordinated configurations are comparatively stable and may be able to function as shallow traps for electron transport. The neutral double unpuckered, neutral back-projected puckered fourfold-coordinated, and neutral back-projected unpuckered configurations are more likely to lose electrons during hole trapping. As the bias voltage is repeatedly changed, the defect density of the puckered configuration may reduce, while that of the dimer and unpuckered configuration may take an opposite trend. [ABSTRACT FROM AUTHOR]

Noting that the conventional collision-dominated electron transport perspective is only relevant when the length scale over which the transit occurs is greater than the electron's mean free path, one can conceptually partition the electron transport "space" into collision-dominated and ballistic electron transport regimes. As the boundaries between these regimes are quite porous, in this analysis, we devise a means of quantitatively examining the transition between electron transport regimes as the length scale is reduced on a continuum basis. Our approach introduces a collision-dominated fractional scattering parameter, this parameter quantifying the fraction of the total scattering rate that arises purely from bulk scattering processes, contact scattering also contributing to the total scattering rate. We pursue this analysis for two conventional semiconductors of interest, silicon and gallium arsenide. A determination of the dependence of the results on both the length scale and the crystal temperature is pursued. Finally, for the specific case of room temperature, a comparison with the results of experiment is performed. [ABSTRACT FROM AUTHOR]

In this manuscript, carrier transport simulation methods are proposed for devices with the coexistence of quantum transport and diffusive transport by combining the nonequilibrium Green's function method with the drift-diffusion transport simulation method. Current continuity between quantum transport and drift-diffusion transport is ensured by setting quantum transport current as the connection boundary condition of drift-diffusion simulation or by introducing quantum transport-induced carrier generation rates to drift-diffusion simulation. A comprehensive study of our method and the method combining the Wentzel–Kramers–Brillouin (WKB) method with the drift-diffusion transport simulation method is performed for n-type tunnel oxide passivating contact solar cell to investigate their applicable conditions and balance the accuracy and computational cost. As the oxide barrier width, barrier height, and electron effective mass increase, or the doping concentration in the electron transport layer decreases to the extent that the blocking effect of the oxide barrier on light-generated electrons becomes significant, method I is more accurate since the transmission coefficient near the conduction band edge calculated by WKB is overestimated; otherwise, method II is more suitable due to its low computational cost without the loss of accuracy. In addition, the differences between current densities, carrier densities, and Shockley–Read–Hall recombination rates simulated under the two current continuity conditions for the solar cell with different carrier mobilities are also further explored and analyzed. [ABSTRACT FROM AUTHOR]

Improving photosynthesis, the fundamental process by which plants convert light energy into chemical energy, is a key area of research with great potential for enhancing sustainable agricultural productivity and addressing global food security challenges. This perspective delves into the latest advancements and approaches aimed at optimizing photosynthetic efficiency. Our discussion encompasses the entire process, beginning with light harvesting and its regulation and progressing through the bottleneck of electron transfer. We then delve into the carbon reactions of photosynthesis, focusing on strategies targeting the enzymes of the Calvin-Benson-Bassham (CBB) cycle. Additionally, we explore methods to increase carbon dioxide (CO2) concentration near the Rubisco, the enzyme responsible for the first step of CBB cycle, drawing inspiration from various photosynthetic organisms, and conclude this section by examining ways to enhance CO2 delivery into leaves. Moving beyond individual processes, we discuss two approaches to identifying key targets for photosynthesis improvement: systems modeling and the study of natural variation. Finally, we revisit some of the strategies mentioned above to provide a holistic view of the improvements, analyzing their impact on nitrogen use efficiency and on canopy photosynthesis.

Traditional leaf gas exchange experiments have focused on net CO2 exchange (Anet). Here, using California poplar (Populus trichocarpa), we coupled measurements of net oxygen production (NOP), isoprene emissions and δ18O in O2 to traditional CO2/H2O gas exchange with chlorophyll fluorescence, and measured light, CO2 and temperature response curves. This allowed us to obtain a comprehensive picture of the photosynthetic redox budget including electron transport rate (ETR) and estimates of the mean assimilatory quotient (AQ = Anet/NOP). We found that Anet and NOP were linearly correlated across environmental gradients with similar observed AQ values during light (1.25 ± 0.05) and CO2 responses (1.23 ± 0.07). In contrast, AQ was suppressed during leaf temperature responses in the light (0.87 ± 0.28), potentially due to the acceleration of alternative ETR sinks like lipid synthesis. Anet and NOP had an optimum temperature (Topt) of 31°C, while ETR and δ18O in O2 (35°C) and isoprene emissions (39°C) had distinctly higher Topt. The results confirm a tight connection between water oxidation and ETR and support a view of light-dependent lipid synthesis primarily driven by photosynthetic ATP/NADPH not consumed by the Calvin-Benson cycle, as an important thermotolerance mechanism linked with high rates of (photo)respiration and CO2/O2 recycling.

Perovskite solar cells have demonstrated exceptional development over the past decade, but their stability remains a challenge toward the application of this technology. Several strategies have been used to address this, and the use of host–guest complexation has recently attracted more interest. However, this approach has primarily been exploited in conventional perovskite solar cells based on n-i-p architectures, while its use in inverted p-i-n devices remains unexplored. Herein, we employ representative crown ether, dibenzo-24-crown-8, for interfacial host–guest complexation in inverted perovskite solar cells based on methylammonium and methylammonium-free formamidinium-cesium halide perovskite compositions. Upon post-treatment of the perovskite films, we observed nanostructures on the surface that were associated with the reduced amount of trap states at the interface with the electron transport layer. As a result, we demonstrate improved efficiencies and operational stabilities following ISOS-D-2I and ISOS-L-2I protocols, demonstrating the viability of this approach to advance device stability. [ABSTRACT FROM AUTHOR]

Porous, stacked two-dimensional covalent organic frameworks (2D COFs) bearing semiconducting linkers can support directional charge transfer across adjacent layers of the COF. To better inform the current and possible future design rules for enhancing electron and hole transport in such materials, an understanding of how linker selection and functionalization affects interlayer electronic couplings is essential. We report electronic structure simulation and analysis of electronic couplings across adjacent linker units and to encapsulated species in functionalized electroactive 2D COFs. The detailed dependence of these electronic couplings on interlayer interactions is examined through scans along key interlayer degrees of freedom and through configurational sampling from equilibrium molecular dynamics on semiempirical potential energy surfaces. Beyond affirming the sensitivity of the electronic coupling to interlayer distance and orientation, these studies offer guidance toward linker functionalization strategies for enhancing charge carrier transport in electroactive 2D COFs. [ABSTRACT FROM AUTHOR]

A generalized quantum master equation approach is introduced to describe electron transfer in molecular junctions that spans both the off-resonant (tunneling) and resonant (hopping) transport regimes. The model builds on prior insights from scattering theory but is not limited to a certain parameter range with regard to the strength of the molecule–electrode coupling. The framework is used to study the simplest case of energy and charge transfer between the molecule and the electrodes for a single site noninteracting Anderson model in the limit of symmetric and asymmetric coupling between the molecule and the electrodes. In the limit of elastic transport, the Landauer result is recovered for the current by invoking a single active electron Ansatz and a binary collision approximation for the memory kernel. Inelastic transport is considered by allowing the excitation of electron–hole pairs in the electrodes in tandem with charge transport. In the case of low bias voltages where the Fermi levels of the electrodes remain below the molecular state, it is shown that the current arises from tunneling and the molecule remains neutral. However, once the threshold is reached for aligning the fermi level of one electrode with the molecular orbital, a small amount of charge transfer occurs with a negligible amount of hopping current. While inelasticity in the current has a minimal impact on the shape of the current–voltage curve in the case of symmetric electrode coupling, the results for a slight asymmetry in coupling demonstrate complete charge transfer and a significant drop in current. These results provide encouraging confirmation that the framework can describe charge transport across a wide range of electrode–molecule coupling and provide a unique perspective for developing new master equation treatments for energy and charge transport in molecular junctions. An extension of this work to account for inelastic scattering from electron–vibrational coupling at the molecule is straightforward and will be the subject of subsequent work. [ABSTRACT FROM AUTHOR]

The photochromic behavior of the fulgide molecule relies on ring-closure and ring-opening processes involving conical intersections during excited state transformation between isomers. The precise location and topography of these conical intersections significantly shape the decay process and fluorescence phenomena inherent to the molecule. This work combines electronic structure theory calculations using the density functional theory and wavefunction methods, as well as surface hopping simulation to analyze the photochemical behavior of an experimentally synthesized fulgide molecule, (E)-p-methylacetophenylisopropylidenesuccinic anhydride (1E). Our study reveals the conical intersection between the first excited state (S1) and the ground electronic state (S0), which emerges beyond the S1 minimum of 1E to the ring-closing side. The distinctive topography of this conical intersection appears to be sloped. These findings suggest a reduced quantum yield for the formation of the closed isomer, indicating a higher likelihood of reformation of the open isomer(s). The surface hopping simulation further supports this observation, revealing a mere ∼8% quantum yield for the formation of the closed isomer. In addition, the photoisomerization of the fulgide molecule initiates a cascade of conduction switching and holds great potential for applications in molecular electronics. Delving into the realm of molecular electronics, we have further examined the electron transport properties, disclosing the higher conductivity of the closed isomer. [ABSTRACT FROM AUTHOR]

Current–voltage characteristics, space- and time-resolved optical emission spectroscopy, and 1D fluid modeling are used to examine the effect of dual-frequency sheath oscillations on the ion and electron transport in dielectric barrier discharges sustained by a combination of low frequency (LF, 50 kHz, 650 V) and radiofrequency (RF, 5.3 MHz, 195 V) voltages, exhibiting the α-to-γ mode transition. On one hand, when polarities of the LF and RF voltages are opposite, an electric field near the LF cathode (due to LF cathode sheath) drives the secondary electrons to the plasma bulk and an opposite electric field between the sheath edge and the LF anode attracts the electrons toward the LF cathode (to maintain quasi-neutrality in the plasma bulk). At the sheath edge, electrons become trapped and ions drift toward the cathode and the anode simultaneously according to their position in the gap. On the other hand, when the RF voltage has the same polarity as the LF voltage, the total applied voltage increases and this yields to enhanced production of electrons and ions in the sheath. To maintain quasi-neutrality in the bulk, the electric field along the gap exhibits the same polarity as the one in the sheath, allowing electrons created in the sheath to be evacuated toward the LF anode. The behavior of the LF cathode is, therefore, controlled by the LF sheath, and, thus, by the LF voltage amplitude, while the behavior in the bulk and at the anode alternates on the time scale of the RF voltage. [ABSTRACT FROM AUTHOR]

Efficient thermoelectric energy conversion at the nanoscale could power the Internet of Things and cool nanoelectronic circuits and improve the performance of quantum applications. Width-modulated nanowaveguides are suitable for these purposes because their thermoelectric efficiency can be geometrically tuned and integrated into the nanoelectronics industry processes. They are attracting increasing research interest stimulated by theoretical predictions for exceptional performance. To validate their potential, a better understanding of the effect of width modulation on thermoelectric efficiency is needed. So far, it is considered that (a) the thermoelectric efficiency increases monotonically with increasing width-mismatch due to decreasing phonon thermal conduction taking place without significantly affecting electron transport, (b) width-mismatch dominates the effect of width modulation in transport, and (c) phonons play the main role in increasing the thermoelectric efficiency. Here, we demonstrate counterevidence based on an investigation of the effect of width modulation on electrons so far overlooked. We reveal that (a) the thermoelectric efficiency varies non-monotonically with the modulation mismatch due to quantum effects on electron transport, (b) the modulation mismatch is quantified by the size-mismatch of the modulation rather than by the width-mismatch, and (c) it is electrons rather than phonons that play the main role in optimizing width modulation for maximum thermoelectric efficiency when quantum effects dominate. Our findings indicate that research should reorient from large width-mismatch toward optimal modulation-mismatch width-modulated nanostructures to enhance thermoelectric efficiency due to quantum effects. Our work provides new insight for designing nanowaveguides for efficient thermoelectric energy conversion at the nanoscale. [ABSTRACT FROM AUTHOR]

Electron emission and transport through and over potential barriers is an essential process requiring modeling and simulation to meet the design needs and characterization of an exceedingly broad range of technologically important devices and processes. The simulation and description of thermal, field, and photoemission, and the related concerns of space–charge affected electron flow, often make use of specialized formulations developed in the early days of quantum mechanics. Advancements in the utilization of electron sources and particularly the simulation of devices and applications using advanced particle-in-cell and trajectory methods for beam optics codes create a strong need for a pedagogical account of the emission models to ensure correct numerical evaluation of their equations. This Tutorial starts from simple phenomenological accounts and progressively builds to comprehensive models emphasizing straightforward and often rapid calculation. It recommends formulations to supplant the canonical Richardson–Laue–Dushman (thermal), Fowler–Nordheim (field), Fowler–DuBridge (photo), and Baroody (secondary) equations and provides a useful formulation of space–charge affected flow commonly described by the Child–Langmuir relation that takes into account cathode dependence on surface field. [ABSTRACT FROM AUTHOR]

We report on the study of electron transport and band offset across β -Ga 2 O 3 /4H-SiC N–n isotype heterojunction. N-type β -Ga 2 O 3 of thickness 2.7 μ m was grown using low-pressure chemical vapor deposition using germanium (Ge) as the dopant on an n-type 4H-SiC substrate. The grown epilayer having (− 201) orientation was verified through XRD. Temperature-dependent I–V and C–V measurements were performed (50–300 K) to investigate the transport properties across the heterojunction. First, lateral diodes were fabricated on β -Ga 2 O 3 , and from C–V, n-doping was estimated to be 2.3 × 10 17 cm − 3 in the epilayer while the Schottky barrier height was estimated to be 1.75 eV. In top-down I–V sweeps, the reverse current across the heterojunction exhibited marginal dependence on temperature, indicating a possible tunnelling-based transport mechanism, while the forward current exhibited an exponential dependence on both temperature and the applied bias. The band diagram indicated the formation of a two-dimensional electron gas (2DEG) at the hetero-interface, which was indirectly confirmed using C–V measurement and TCAD simulation at low temperatures. From the position of the Fermi level in SiC and band diagram, a conduction band offset of 0.4–0.5 eV was estimated between β -Ga 2 O 3 and 4H-SiC. [ABSTRACT FROM AUTHOR]

In recent years, organic–inorganic hybrid perovskite (PVK) devices have attracted widespread attention with their high absorption coefficient and low-cost fabrication process. Formamidinium lead iodide (FAPbI3) perovskite solar cells (PSCs) have been reported to obtain high power conversion efficiencies (PCEs) due to the narrow bandgap. Zinc oxide (ZnO) has better electrical conductivity and high transmittance than tin (IV) dioxide (SnO2). However, the deprotonation behavior of ZnO limits its use in formamidinium (FA) or methylammonium (MA) devices, so it is mostly used in all-inorganic PSCs. In this work, to avoid the deprotonation behavior of ZnO, we prepared FAPbI3 PSCs using ZnO/SnO2 as bilayer electron transporting layers (ETLs), which improved the conductivity of the ETLs and promoted electron extraction and transfer. In addition, the decrease in the oxygen vacancy (Ov) on the bilayer ETLs contributed to the suppression of the non-radiative recombination of the device, thus enabling the achievement of a higher fill factor. As a result, the modified ETLs increased the PCE of FAPbI3 PSCs from 20.24% to 21.42% and improved the stability of the devices. The PCE of unpackaged devices increased steadily to 21.91% when stored in an N2 atmosphere for 183 days. [ABSTRACT FROM AUTHOR]

Methanogens are a diverse group of Archaea that obligately couple energy conservation to the production of methane. Some methanogens encode alternate pathways for energy conservation, like anaerobic respiration, but the biochemical details of this process are unknown. We show that a multiheme c-type cytochrome called MmcA from Methanosarcina acetivorans is important for intracellular electron transport during methanogenesis and can also reduce extracellular electron acceptors like soluble Fe3+ and anthraquinone-2,6-disulfonate. Consistent with these observations, MmcA displays reversible redox features ranging from -100 to -450 mV versus SHE. Additionally, mutants lacking mmcA have significantly slower Fe3+ reduction rates. The mmcA locus is prevalent in members of the Order Methanosarcinales and is a part of a distinct clade of multiheme cytochromes that are closely related to octaheme tetrathionate reductases. Taken together, MmcA might act as an electron conduit that can potentially support a variety of energy conservation strategies that extend beyond methanogenesis.

Rutile-type wide and ultrawide band-gap oxide semiconductors are emerging materials for high-power electronics and deep ultraviolet optoelectronics applications. A rutile-type GeO2-SnO2 alloy (r-GexSn1–xO2) recently found is one of such materials. Herein, we report low-temperature electron transport properties of r-GexSn1−xO2 thin films with x = 0.28 and 0.41. Based on resistivity and magnetoresistance measurements, along with the theory of quantum interference, it is suggested that Efros–Shklovskii variable-range hopping, i.e., hopping over the states within the Coulomb gap, is dominant at lower temperatures (T ≤ 10 and 15 K) in both r-Ge0.41Sn0.59O2 and r-Ge0.28Sn0.72O2. The negative and positive magnetoresistances observed at low temperatures are attributable to the quantum interference and field-induced spin alignment, respectively. The magnetoresistance measurements at higher temperatures suggest that both Mott variable–range hopping and thermally activated band conduction occur at T < 100 K and that almost pure thermally activated band conduction takes place at T ≥ 150 K. [ABSTRACT FROM AUTHOR]

Rutile-type wide and ultrawide band-gap oxide semiconductors are emerging materials for high-power electronics and deep ultraviolet optoelectronics applications. A rutile-type GeO2-SnO2 alloy (r-GexSn1–xO2) recently found is one of such materials. Herein, we report low-temperature electron transport properties of r-GexSn1−xO2 thin films with x = 0.28 and 0.41. Based on resistivity and magnetoresistance measurements, along with the theory of quantum interference, it is suggested that Efros–Shklovskii variable-range hopping, i.e., hopping over the states within the Coulomb gap, is dominant at lower temperatures (T ≤ 10 and 15 K) in both r-Ge0.41Sn0.59O2 and r-Ge0.28Sn0.72O2. The negative and positive magnetoresistances observed at low temperatures are attributable to the quantum interference and field-induced spin alignment, respectively. The magnetoresistance measurements at higher temperatures suggest that both Mott variable–range hopping and thermally activated band conduction occur at T < 100 K and that almost pure thermally activated band conduction takes place at T ≥ 150 K. [ABSTRACT FROM AUTHOR]

Metal-reducing bacteria have adapted the ability to respire extracellular solid surfaces instead of soluble oxidants. This process requires an electron transport pathway that spans from the inner membrane, across the periplasm, through the outer membrane, and to an external surface. Multiheme cytochromes are the primary machinery for moving electrons through this pathway. Recent studies show that the chiral-induced spin selectivity (CISS) effect is observable in some of these proteins extracted from the model metal-reducing bacteria, Shewanella oneidensis MR-1. It was hypothesized that the CISS effect facilitates efficient electron transport in these proteins by coupling electron velocity to spin, thus reducing the probability of backscattering. However, these studies focused exclusively on the cell surface electron conduits, and thus, CISS has not been investigated in upstream electron transfer components such as the membrane-associated MtrA, or periplasmic proteins such as small tetraheme cytochrome (STC). By using conductive probe atomic force microscopy measurements of protein monolayers adsorbed onto ferromagnetic substrates, we show that electron transport is spin selective in both MtrA and STC. Moreover, we have determined the spin polarization of MtrA to be ∼77% and STC to be ∼35%. This disparity in spin polarizations could indicate that spin selectivity is length dependent in heme proteins, given that MtrA is approximately two times longer than STC. Most significantly, our study indicates that spin-dependent interactions affect the entire extracellular electron transport pathway. [ABSTRACT FROM AUTHOR]

The lattice mismatch, defect, and weak interlayer coupling severely constrain the practical application of van der Waals heterojunctions (vdWHs) in the field of optoelectronic devices. Here, we introduced the 2D ferroelectric (FE) material AgBiP2Se6 to construct defect-free, low lattice-mismatched AgBiP2Se6/MoSe2 heterojunctions with different polariton directions (I, II, III). The AgBiP2Se6 layer can provide an excellent FE electric field to enhance the interlayer coupling and stiffness. The larger interlay stiffness reduces the probability of electron–phonon scattering and then results in significant carrier mobility (∼0.5 × 104 cm2 V−1 s−1) for configurations I and II. Phase transition of FE to paraelectric AgBiP2Se6 in the AgBiP2Se6/MoSe2 heterojunctions can be achieved under specific biaxial strain, which can effectively regulate the electronic structure. Applying the strain and electric field can regulate the bandgap and band alignment of configurations I and II. The photoelectric conversion efficiency of configuration I can reach as high as 20.54% under 2% biaxial strain. Furthermore, configuration II holds a nearly free electron state near the Fermi level under an electric field, which can act as a favorable electron transport channel. A design to strengthen interlayer coupling in the FE-based AgBiP2Se6/MoSe2 heterojunction has been proposed, and it can provide a new way to break through the traditional bottleneck in the development of optoelectronic devices. [ABSTRACT FROM AUTHOR]

We demonstrate a high electron conductivity (>102 S/cm and up to 103 S/cm) of tungsten suboxide W18O52.4−52.9 (or equivalently WO2.91−2.94) nanotubes (2–3 nm in diameter, ∼μm long). The conductivity is measured in the temperature range of 120–300 K by a four-probe scanning tunneling microscope in ultrahigh vacuum. The nanotubes are synthesized by a low-temperature and low-cost solvothermal method. They self-assemble in bundles of hundreds of nanotubes forming nanowires (∼μm long, few tens nm wide). We observe a large anisotropy of the conductivity with a ratio (longitudinal conductivity/perpendicular conductivity) of ∼105. A large fraction of them (∼65%–95%) shows a metallic-like, thermal activation-less electron transport behavior. Few of them, with a lower conductivity from 10 to 102 S/cm, display a variable range hopping behavior. In this latter case, a hopping barrier energy of ∼0.24 eV is inferred in agreement with the calculated energy level of the oxygen vacancy below the conduction band. This result is in agreement with a relative average concentration of oxygen vacancies of ∼3%, for which a semiconductor-to-metal transition was theoretically predicted. These tungsten suboxide nanostructures are prone to a wide range of applications in nanoelectronics. [ABSTRACT FROM AUTHOR]

Within the framework of an electron transport regime classification scheme, we aim to explore the boundaries that occur between the ballistic, collision-dominated, space-charge injection, and non-space-charge injection electron transport regimes that are experienced by an electron within a semiconducting device, mapping out where these different electron transport regimes are. We do this by determining the electron's mean free path and the relevant screening length. In order to make this analysis concrete, we perform this analysis for four representative semiconductor material systems, including silicon, gallium arsenide, the 4H-phase of silicon carbide, and the wurtzite phase of gallium nitride. The entire analysis is performed using a two-dimensional approach, this being representative of the electron transport that is experienced by an electron in the vicinity of a two-dimensional electron gas. Finally, following an evaluation of the dependence of the ballistic mobility on the device length scale for all four materials, an evaluation of the effective mobility as a function of the channel-length scale is pursued, a Matthiessen-rule based approach being employed for the purposes of this analysis. [ABSTRACT FROM AUTHOR]

The electron transport characteristics of magnetic and non-magnetic ferroelectric tunnel junctions based on Hf 0.5 Zr 0.5 O 2 are investigated in this study. A modified linear approach to the Thomas–Fermi interfacial screening model is employed to simulate these properties. This method is developed by leveraging the quantum approximation of the quasiclassical spin-resolved point-like contact formalism. The oxygen vacancies, voltage-induced screening, and electrostriction effect are the key phenomena exploited to build the potential profile and hence to simulate the resistive switching characteristics of the ferroelectric tunnel junctions. To validate its precision, the model is extensively verified with experimental data. The obtained model is generalized to reproduce mono-domain and multi-domain ferroelectric switching, featuring its effectiveness for non-volatile storage devices and ferroelectric-field effect transistors. [ABSTRACT FROM AUTHOR]

A memristor is a two-terminal electrical component with the scope of future computing applications and analog electronics. In this report, bismuth sulfide decorated one-dimensional carbon nitride nanotube was synthesized and characterized with various analytical techniques. The electrical property of the synthesized material was measured using a two-terminal metal–insulator–metal type of device that exhibited the resistive switching characteristics with the ON to OFF ratio of 2 × 103. The electron transport mechanism of the device was followed by Schottky emission and Poole–Frenkel emission for a low conductance state and Ohmic conduction behavior at the high conductance state. A decrease in the trap depth was identified in the simulation study with increasing applied potential and that supported the proposed mechanism. Read endurance and retention behavior of the device are stable in nature, supported by the statistical analysis. Furthermore, a hybrid logic gate was designed using two identical memristors, one CMOS inverter, one resistor, one voltage divider, and a buffer gate. The designed logic gate exhibited stable nand and nor gate operation based on the control signal. [ABSTRACT FROM AUTHOR]

The dynamics of (few) electrons dissolved in an ionic fluid—as when a small amount of metal is added to a solution while upholding its electronic insulation—manifests interesting properties that can be ascribed to nontrivial topological features of particle transport (e.g., Thouless' pumps). In the adiabatic regime, the charge distribution and the dynamics of these dissolved electrons are uniquely determined by the nuclear configuration. Yet, their localization into effective potential wells and their diffusivity are dictated by how the self-interaction is modeled. In this article, we investigate the role of self-interaction in the description of the localization and transport properties of dissolved electrons in non-stoichiometric molten salts. Although the account for the exact (Fock) exchange strongly localizes the dissolved electrons, decreasing their tunneling probability and diffusivity, we show that the dynamics of the ions and of the dissolved electrons are largely uncorrelated, irrespective of the degree to which the electron self-interaction is treated and in accordance with topological arguments. [ABSTRACT FROM AUTHOR]

Electron bifurcation (BF) is an evolutionarily ancient energy coupling mechanism in anaerobes, whose associated enzymatic machinery remains enigmatic. In BF-flavoenzymes, a chemically high-potential electron forms in a thermodynamically favorable fashion by simultaneously dropping the potential of a second electron before its donation to physiological acceptors. The cryo-EM and spectroscopic analyses of the BF-enzyme Fix/EtfABCX from Thermotoga maritima suggest that the BF-site contains a special flavin-adenine dinucleotide and, upon its reduction with NADH, a low-potential electron transfers to ferredoxin and a high-potential electron reduces menaquinone. The transfer of energy from high-energy intermediates must be carefully orchestrated conformationally to avoid equilibration. Herein, anaerobic size exclusion-coupled small-angle X-ray scattering (SEC-SAXS) shows that the Fix/EtfAB heterodimer subcomplex, which houses BF- and electron transfer (ET)-flavins, exists in a conformational equilibrium of compacted and extended states between flavin-binding domains, the abundance of which is impacted by reduction and NAD(H) binding. The conformations identify dynamics associated with the T. maritima enzyme and also recapitulate states identified in static structures of homologous BF-flavoenzymes. Reduction of Fix/EtfABCX's flavins alone is insufficient to elicit domain movements conducive to ET but requires a structural "trigger" induced by NAD(H) binding. Models show that Fix/EtfABCX's superdimer exists in a combination of states with respect to its BF-subcomplexes, suggesting a cooperative mechanism between supermonomers for optimizing catalysis. The correlation of conformational states with pathway steps suggests a structural means with which Fix/EtfABCX may progress through its catalytic cycle. Collectively, these observations provide a structural framework for tracing Fix/EtfABCX's catalysis.

Photosystem I (PSI) serves as a model system for studying fundamental processes such as electron transfer (ET) and energy conversion, which are not only central to photosynthesis but also have broader implications for bioenergy production and biomimetic device design. In this study, we employed electron paramagnetic resonance (EPR) spectroscopy to investigate key light-induced charge separation steps in PSI isolated from several green algal and cyanobacterial species. Following photoexcitation, rapid sequential ET occurs through either of two quasi-symmetric branches of donor/acceptor cofactors embedded within the protein core, termed the A and B branches. Using high-frequency (130 GHz) time-resolved EPR (TR-EPR) and deuteration techniques to enhance spectral resolution, we observed that at low temperatures prokaryotic PSI exhibits reversible ET in the A branch and irreversible ET in the B branch, while PSI from eukaryotic counterparts displays either reversible ET in both branches or exclusively in the B branch. Furthermore, we observed a notable correlation between low-temperature charge separation to the terminal [4Fe-4S] clusters of PSI, termed FA and FB, as reflected in the measured FA/FB ratio. These findings enhance our understanding of the mechanistic diversity of PSI's ET across different species and underscore the importance of experimental design in resolving these differences. Though further research is necessary to elucidate the underlying mechanisms and the evolutionary significance of these variations in PSI charge separation, this study sets the stage for future investigations into the complex interplay between protein structure, ET pathways, and the environmental adaptations of photosynthetic organisms.

Photocatalysts for hydrogen evolution reaction (HER) have widely been explored but fine-tuning and engineering multiphase photocatalyst components are still challenging. Among catalysts, ZnIn 2 S 4 has shown promise but maximizing the use of ZnIn 2 S 4 -photogenerated carriers and enhancing quantum yield still require further investigation. One way to achieve this is by enhancing the photon utilization and reducing the recombination of shallow carriers in ZnIn 2 S 4. Accordingly, novel ZnIn 2 S 4 /g-C 3 N 4 /MoS 2 type-II heterojunction composites with 2D/2D/2D structures (abbreviated ZIS/CN/MS) were synthesized in the present work by simple thermal condensation-solvothermal method. The optimized ZIS/CN/MS exhibited a photocatalytic hydrogen evolution rate of 13.6 mmol g−1 h−1 under visible light (λ ≥ 420 nm) irradiation, a value much higher than those of pure-phases ZIS and CN, as well as the binary composite of ZIS/CN. The apparent quantum efficiency of the optimized ZIS/CN/MS at a wavelength of 420 nm reached 27.0 % coupled with excellent cycling stability. The significantly improved photocatalytic performance and the excellent stability can mainly be attributed to the unique 2D/2D/2D arrangement of the ternary components of ZIS, CN, and MS in ZIS/CN/MS photocatalyst, providing a large number of close interfacial contacts between the components for shortened migration distance of photogenerated charges and more pathways for electron separation and transport in type-II heterostructures. Overall, the proposed methodology and ZIS/CN/MS composites with type-II heterojunction and 2D/2D/2D structures have great potential for use in solar-to-hydrogen energy conversion and can be extended to the preparation of other photocatalysts. [Display omitted] • 2D/2D/2D ZnIn 2 S 4 /g-C 3 N 4 /MoS 2 hybrid junction enhances dielectric properties. • New structure provides close interfacial contact and pathway for electron separation. • Unique 2D/2D/2D arrangement improves photocatalytic performance and stability. [ABSTRACT FROM AUTHOR]

Ethylene glycol (EG) is a widely used material, but its vapor is harmful to human health already in low concentrations. Thus, highly sensitive EG gas sensors are urgently needed. Herein, a series samples of ZnO and carbon dots (CDs) were synthesized at different ratios through a simple mechanical grinding method. The senor made using ZnO/CDs2 exhibits an ultra-high response (Ra/Rg) to 100 ppm EG up to 2798, 1378 and 467, and extremely low detection limit as low as 21 ppb, 13 ppb and 2 ppb, under UV light, visible light, and infrared light, respectively, as well as excellent repeatability and long-term stability. Especially, under UV light irradiation, the response of ZnO/CDs2 to 100 ppm EG is 24 times that of pure ZnO (Ra/Rg = 114.7), and more than 71 times that of 9 other gases. The outstanding gas sensing performance of ZnO/CDs2 can be attributed to the excellent light response ability of CDs at first, which greatly enriches the electron concentration in ZnO/CDs under light irradiation. Furthermore, the photo-induced electron transfer (PET) property of CDs and the p-n heterojunction formed at the interface between ZnO and CDs play a key role in rapid electron transport and transfer, avoiding a large number of electron hole recombination. [ABSTRACT FROM AUTHOR]

The enhancement in the capacitance of a supercapacitor has been successfully achieved by synthesizing Bi 2 WO 6 (BW), TiS 2 (T), and Bi 2 WO 6 /TiS 2 (BW/T) composites utilizing the hydrothermal process. The possible growth mechanism has also been presented. The morphological and structural characteristics of the cultivated samples were observed using FT-IR, XRD, SEM, EDS, and UV–vis spectroscopy techniques. TiS 2 nano platelets uniformly dispersed across the hierarchically opened surface of Bi 2 WO 6 in the synthesized hierarchical composite. This leads to an increase in surface porosity and surface area, which in turn enhances the transport of electrons and ions on the composite BW/T surface. The optimal electrode BW/T@40 % composite electrode shown a substantial enhancement in particular capacitance (1153.3 F/g) compared to the separate BW (523.7 F/g) and T (453.3 F/g) electrodes due to its rapid ion transfer, many active sites on its large surface area, and strong synergistic impact. Furthermore, the BW/T@40 % combination demonstrated exceptional stability, with over 92 % of its capacitance maintained after 4500th cycles and b value (0.71) proved the supercapacitor behavior. Therefore, BW/T@40 % binary metal oxide and sulfide composites exhibit improved specific capacitance and greatly prolonged life-cycle, confirming its potential use in high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

The Ag-PSi@SiC@C electrode features a substantially higher lithium-ion mobility of 2.4 × 10−9 cm2·s−1, which is significantly greater than the mobility of silicon at 5.1 × 10−12 cm2·s−1. With this anode, the half-cell exhibits excellent rate capability and cycling stability at a current density of 2.0 A/g, with a capacity of 1321.7 mAh/g that is maintained over 200 cycles, dropping only to 962.6 mAh/g. [Display omitted] Silicon-based material is regarded as one of the most promising anodes for next-generation high-performance lithium-ion batteries (LIBs) due to its high theoretical capacity and low cost. Harnessing silicon carbide's robustness, we designed a novel porous silicon with a sandwich structure of carbon/silicon carbide/Ag-modified porous silicon (Ag-PSi@SiC@C). Different from the conventional Si C interface characterized by a frail connection, a robust dual covalent bond configuration, dependent on Si C and Si O C, has been successfully established. Moreover, the innovative sandwich structure effectively reduces detrimental side reactions on the surface, eases volume expansion, and bolsters the structural integrity of the silicon anode. The incorporation of silver nanoparticles contributes to an improvement in overall electron transport capacity and enhances the kinetics of the overall reaction. Consequently, the Ag-PSi@SiC@C electrode, benefiting from the aforementioned advantages, demonstrates a notably elevated lithium-ion mobility (2.4 * 10−9 cm2·s−1), surpassing that of silicon (5.1 * 10−12 cm2·s−1). The half-cell featuring Ag-PSi@SiC@C as the anode demonstrated robust rate cycling stability at 2.0 A/g, maintaining a capacity of 1321.7 mAh/g, and after 200 cycles, it retained 962.6 mAh/g. Additionally, the full-cell, featuring an Ag-PSi@SiC@C anode and a LiFePO 4 (LFP) cathode, exhibits outstanding longevity. Hence, the proposed approach has the potential to unearth novel avenues for the extended exploration of high-performance silicon-carbon anodes for LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Sluggish kinetics and severe structural instability of manganese-based cathode materials for rechargeable aqueous zinc-ion batteries (ZIBs) lead to low-rate capacity and poor cyclability, which hinder their practical applications. Pillaring manganese dioxide (MnO 2) by pre-intercalation is an effective strategy to solve the above problems. However, increasing the pre-intercalation content to realize stable cycling of high capacity at large current densities is still challenging. Here, high-rate aqueous Zn2+ storage is realized by a high-capacity K+-pillared multi-nanochannel MnO 2 cathode with 1 K per 4 Mn (δ-K 0.25 MnO 2). The high content of the K+ pillar, in conjunction with the three-dimensional confinement effect and size effect, promotes the stability and electron transport of multi-nanochannel layered MnO 2 in the ion insertion/removal process during cycling, accelerating and accommodating more Zn2+ diffusion. Multi-perspective in/ex-situ characterizations conclude that the energy storage mechanism is the Zn2+/H+ ions co-intercalating and phase transformation process. More specifically, the δ-K 0.25 MnO 2 nanospheres cathode delivers an ultrahigh reversible capacity of 297 mAh g−1 at 1 A g−1 for 500 cycles, showing over 96 % utilization of the theoretical capacity of δ-MnO 2. Even at 3 A g−1, it also delivered a 63 % utilization and 64 % capacity retention after 1000 cycles. This study introduces a highly efficient cathode material based on manganese oxide and a comprehensive analysis of its structural dynamics. These findings have the potential to improve energy storage capabilities in ZIBs significantly. [ABSTRACT FROM AUTHOR]

Superconducting hybrid structures based on single nanowires are a new type of nanoscale devices with peculiar transport characteristics. Control over the nanowire structure is essential for understanding hybrid electronic phenomena arising in such complex systems. In this work, we report a technique for the fabrication of cobalt nanowires by template-assisted electrodeposition using iR compensation, which allows revealing the fundamental dependence of the preferred direction of nanowire growth on the deposition potential. Long coarse-grained cobalt nanowires with a diameter of 70 nm have been implemented into Nb/Co/Nb hybrid structures. We demonstrate that using electrode fabrication techniques that do not contaminate the surface of the nanowire leads to a high quality of devices with low-resistance interfaces. Low-temperature resistivity of 4.94 ± 0.83 µ Ω cm and other transport characteristics of Co nanowires are reported. The absence of long-range superconducting proximity effect for Nb/Co/Nb systems with different nanowire length is discussed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Layer‐by‐layer (LbL) solution processing is an efficient method to realize high performance organic solar cells (OSCs). One of the drawbacks of the LbL‐processed active layer is the large difference in the crystallinity of the donor and acceptor, which will lead to imbalance charge transfer and result in unfavorable charge recombination. Herein, we combined a novel volatile additive 3,5‐dichloro‐2,4,6‐ trifluorobenzotrifluoride (DTBF) with the LbL method to realize high‐efficiency OSCs. DTBF interacts with the non‐fullerene acceptor BTP‐4F by non‐covalent bonding, which enhances the crystallinity and compact stacking of BTP‐4F. DTBF doped OSC has balanced and efficient electron transport properties, longer carrier lifetime, higher exciton dissociation and charge collection efficiencies, lower energetic disorder than the control OSC without any additives. Benefiting from the optimization of charge dynamics and micro‐morphology by DTBF, the binary LbL‐processed OSC achieved synergistic improvements in open‐circuit voltage, short‐circuit current density and fill factor. As a result, a champion power conversion efficiency (PCE) of 19% is realized for DTBF‐optimized OSC, which is superior to the control OSC (17.55%). This work demonstrates a promising approach to modulate active layer morphology and fabricate high performance OSCs. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production is one of the most valuable technologies in the future energy system. Here, we designed a metal‐covalent organic frameworks (MCOFs) with both small‐sized metal clusters and nitrogen‐rich ligands, named COF‐Cu3TG. Based on our design, small‐sized metal clusters were selected to increase the density of active sites and shorten the distance of electron transport to active sites. While another building block containing nitrogen‐rich organic ligands acted as a node that could in situ anchor metal atoms during photocatalysis and form interlayer single‐atom electron bridges (SAEB) to accelerate electron transport. Together, they promoted photocatalytic performance. This represented the further utilization of Ru atoms and was an additional application of the photosensitizer. N2‐Ru‐N2 electron bridge (Ru‐SAEB) was created in situ between the layers, resulting in a considerable enhancement in the hydrogen production rate of the photocatalyst to 10.47 mmol g−1 h−1. Through theoretical calculation and EXAFS, the existence position and action mechanism of Ru‐SAEB were reasonably inferred, further confirming the rationality of the Ru‐SAEB configuration. A sufficiently proximity between the small‐sized Cu3 cluster and the Ru‐SAEB was found to expedite electron transfer. This work demonstrated the synergistic impact of small molecular clusters with Ru‐SAEB for efficient photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Developing highly efficient catalysts for the hydrogen evolution reaction (HER) is crucial for advancing renewable hydrogen energy technologies. Heterophase nanomaterials have shown great promise in catalysis, owing to the synergistic effect among various phases and the abundance of active sites located at the phase boundaries or interfaces. However, achieving precise control over these phase structures during synthesis remains a significant challenge. In this work, we explored a one-pot synthesis method for amorphous/crystalline heterophase Rh nanoparticles, with crystallinity tunable by adjusting the quantity of urea and reaction duration. Due to the increased electrochemical active sites, enhanced electron transport, the resulting amorphous/crystalline heterophase Rh exhibits superior HER activities in both acidic (with an overpotential of 27 mV) and alkaline media (with an overpotential of 21 mV), surpassing that of commercial Pt/C and crystalline Rh. Theoretical calculations indicate that the amorphous/crystalline structure reduces the kinetic barrier for water splitting and optimizes adsorption free energy of hydrogen (ΔG H∗), thereby enabling the catalyst to exhibit significantly enhanced HER performance. This exploration offers a valuable reference for designing amorphous/crystalline heterophase structures and demonstrates the great potential of phase engineering strategy in the development of electrocatalysts. [Display omitted] • Amorphous/crystalline heterophase Rh can be prepared with urea in a simple method. • The crystallinity can be tuned by modifying the amount of urea and reaction time. • Amorphous/crystalline Rh exhibited a higher HER performance than crystalline Rh. • Amorphous/crystalline structure optimizes adsorption energy of reactant. [ABSTRACT FROM AUTHOR]

Adjusting the morphology and structure of the catalyst to optimize the structure of the discharge product is an effective strategy for improving the electrocatalytic activity of lithium–oxygen batteries (LOBs). In this paper, a novel high‐orientation layered manganese‐based metal–organic frameworks (Mn‐MOFs) catalyst for the air cathode of a LOB is synthesized via a facile solvothermal method using 2,4‐pyridine dicarboxylic acid combined with the metal Mn2+ ion. The presence of layered structure increases the specific surface area of the catalytic material, and the interlayer spacing can be used as a channel for electron and oxygen transport, thus promoting ion diffusion and catalyzing reactions. Otherwise, the coordination of the N element and metal ion in the organic ligand significantly improves the electrical conductivity and oxygen reduction reaction/oxygen extraction reaction (ORR/OER) performance of LOB. The effective combination of Mn2+ and 2,4‐pyridine dicarboxylic acid improves the overall catalytic capacity of the material, leading to a high LiO2 adsorption capacity so as to induce the formation of film discharge products and extend the cycle life of LOBs. When using Mn‐MOFs at 140°C as the cathode catalyst, the specific discharge capacity of the LOB can achieve 5579 mAh/g with a 0.2 mA/cm2 current density and maintain 140 stable cycles, limiting the specific discharge capacity to 500 mAh/g. [ABSTRACT FROM AUTHOR]

Background and Purpose: Triple‐negative breast cancer (TNBC) has a poor prognosis due to limited therapeutic options. Recent studies have shown that TNBC is highly dependent on mitochondrial oxidative phosphorylation. The aim of this study was to investigate the potential of coptisine, a novel compound that inhibits the complex I of the mitochondrial electron transport chain (ETC), as a treatment for TNBC. Experimental Approach: In this study, mitochondrial metabolism in TNBC was analysed by bioinformatics. In vitro and in vivo experiments (in mice) were conducted to evaluate the potential of coptisine as an ETC complex I‐targeting therapeutic agent and to investigate the molecular mechanisms underlying coptisine‐induced mitochondrial dysfunction. The therapeutic effect of coptisine was assessed in TNBC cells and xenograft mouse model. Key Results: We demonstrated that mitochondrial ETC I was responsible for this metabolic vulnerability in TNBC. Furthermore, a naturally occurring compound, coptisine, exhibited specific inhibitory activity against this complex I. Treatment with coptisine significantly inhibited mitochondrial functions, reprogrammed cellular metabolism, induced apoptosis and ultimately inhibited the proliferation of TNBC cells. Additionally, coptisine administration induced prominent growth inhibition that was dependent on the presence of a functional complex I in xenograft mouse models. Conclusion and Implications: Altogether, these findings suggest the promising potential of coptisine as a potent ETC complex I inhibitor to target the metabolic vulnerability of TNBC. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeCoNiP and FeNi-LDH hierarchical multilevel structures are constructed on CuO nanowires. • FeCoNiP@FeNi-LDH@CuO/CF exhibits excellent performance for overall water splitting in alkaline medium. • The hierarchical multilevel structure provides more active sites and accelerates the electron transport rate. • The CuO nanowire array structure improves the catalyst hydrophilic and aerophobic properties. In response to the growing demand for clean, green, and sustainable energy sources, the development of cost-effective and durable high-activity overall water splitting electrocatalysts is urgently needed. In this study, the heterogeneous structure formed by the combination of FeCoNiP and FeNi-LDH was homogeneously dispersed onto CuO nanowires generated by in-situ oxidation of copper foam as a substrate using an electrodeposition method. This multilevel structure exhibits excellent bifunctional properties as an electrode material in alkaline solutions, for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) only 206 mV and 147 mV overpotentials are needed to achieve a current density of 100 mA cm−2 respectively. Full water electrolysis is thus enabled to take place at such a low cell voltage as 1.64 V to reach the current density of 100 mA cm−2, which exhibits a long-term stability of 30 h. These improved electrocatalytic performances stem from the construction of multilevel structures. The X-ray photoelectron spectroscopy suggests that strong electron transfer occurs between heterogeneous structures, thus facilitating the OER and HER process. The dispersion of CuO nanowires not only increases the electrochemically active surface areas but also improves the overall hydrophilic and aerophobic properties. This work highlights the positive effect of multilevel structure in the design of more efficient electrocatalysts and provides a reference for the preparation of other low-cost, high-activity bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

Inspired by the "electric jellyfish group" in the ocean, the Ti O H O strong correlation strategy is first proposed and used to construct Hexagon MXene heterojunction for potassium-ions hybrid supercapacitor with high energy density. The adsorption rules and electron transport mechanism of potassium-ions at the Ti O H O interface revealed in this work provide valuable insights into the regulation of ions/electrons at the energy storage interface. [Display omitted] • Inspired by the "electric jellyfish group" in the ocean, the Ti O H O strong correlation strategy is first proposed and used to construct Hexagon MXene heterojunction for potassium-ions hybrid supercapacitor with high energy density. • The Ti O H O interface not only effectively improves the adsorption capacity and adsorption energy of potassium-ions, but also provides a fast channel for electron transport, thus obtaining a remarkable rate performance in neutral electrolyte. • The adsorption rules and electron transport mechanism of potassium-ions at the Ti O H O interface revealed in this work provide valuable insights into the regulation of ions/electrons at the energy storage interface. Potassium-ion hybrid capacitors (PIHC) are considered as ideal large-scale rechargeable energy storage devices due to their low-cost, high-power density and environmental protection. However, a low energy density is the main factor restricting the practical application of PIHC. The interface is formed on the surface of electrode material of PIHC through strong correlation to construct heterojunction, which can significantly improve the performance of ion energy storage. However, how to reveal the influence of the interfacial state of the heterojunction on the adsorption and electron transmission of energy storage ions at the atomic level is still one of the key scientific problems in this field. In this work, metal ion intercalation and microwave-assisted in-situ etching are used to construct the Hexagon MXene Ti 3 C 2 heterojunction with Ti O H O strong correlation. At the interface of heterojunction, Ti O H O highway for electron transmission is developed to improve the rate performance of PIHC. Through experimental and theoretical calculation, the optimum adsorption position and maximum adsorption amount of potassium-ion at the single interface of heterojunction are obtained, and the specific energy density of PIHC is increased. This lays a foundation for the practical application of high-performance soft-package PIHC. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) after undergoing the superlithiation process promise high‐capacity anodes while suffering from sluggish reaction kinetics and low electrochemical utilization of redox‐active sites. Herein, integrating carbon nanotubes (CNTs) with imine‐linked covalent organic frameworks (COFs) was rationally executed by in‐situ Schiff‐base condensation between 1,1′‐biphenyl]‐3,3′,5,5′‐tetracarbaldehyde and 1,4‐diaminobenzene in the presence of CNTs to produce core–shell heterostructured composites (CNT@COF). Accordingly, the redox‐active shell of COF nanoparticles around one‐dimensional conductive CNTs synergistically creates robust three‐dimensional hybrid architectures with high specific surface area, thus promoting electron transport and affording abundant active functional groups accessible for electrochemical utilization throughout the whole electrode. Remarkably, upon the full activation with a superlithiation process, the as‐fabricated CNT@COF anode achieves a specific capacity of 2324 mAh g−1, which is the highest specific capacity among organic electrode materials reported so far. Meanwhile, the superior rate capability and excellent cycling stability are also obtained. The redox reaction mechanisms for the COF moiety were further revealed by Fourier‐transform infrared spectroscopy in conjunction with X‐ray photoelectron spectroscopy, involving the reversible redox reactions between lithium ions and C=N groups and gradual electrochemical activation of the unsaturated C=C bonds within COFs. [ABSTRACT FROM AUTHOR]

We employ advanced first principles methodology, merging self‐consistent phonon theory and the Boltzmann transport equation, to comprehensively explore the thermal transport and thermoelectric properties of KCdAs. Notably, the study accounts for the impact of quartic anharmonicity on phonon group velocities in the pursuit of lattice thermal conductivity and investigates 3ph and 4ph scattering processes on phonon lifetimes. Through various methodologies, including examining atomic vibrational modes and analyzing 3ph and 4ph scattering processes, the article unveils microphysical mechanisms contributing to the low κL within KCdAs. Key features include significant anisotropy in Cd atoms, pronounced anharmonicity in K atoms, and relative vibrations in non‐equivalent As atomic layers. Cd atoms, situated between As layers, exhibit rattling modes and strong lattice anharmonicity, contributing to the observed low κL. Remarkably flat bands near the valence band maximum translate into high PF, aligning with ultralow κL for exceptional thermoelectric performance. Under optimal temperature and carrier concentration doping, outstanding ZT values are achieved: 4.25 (a(b)‐axis, p‐type, 3 × 1019 cm−3, 500 K), 0.90 (c‐axis, p‐type, 5 × 1020 cm−3, 700 K), 1.61 (a(b)‐axis, n‐type, 2 × 1018 cm−3, 700 K), and 3.06 (c‐axis, n‐type, 9 × 1017 cm−3, 700 K). [ABSTRACT FROM AUTHOR]

Acrylamide (AAM), a compound extensively utilized in various industrial applications, has been reported to induce toxic effects across multiple tissues in living organisms. Despite its widespread use, the impact of AAM on ovarian function and the mechanisms underlying these effects remain poorly understood. Here, we established an AAM‐exposed mouse toxicological model using 21 days of intragastric AAM administration. AAM exposure decreased ovarian coefficient and impaired follicle development. Further investigations revealed AAM would trigger apoptosis and disturb tricarboxylic acid cycle in ovarian tissue, thus affecting mitochondrial electron transport function. Moreover, AAM exposure decreased oocyte and embryo development potential, mechanically associated with pericentrin and phosphorylated Aurora A cluster failure, leading to meiotic spindle assembly defects. Collectively, these results suggest that AAM exposure may lead to apoptosis, glucose metabolic disorders, and mitochondrial dysfunction in ovary tissue, ultimately compromising oocyte quality. [ABSTRACT FROM AUTHOR]

Construction of advanced carbon material is critical for the development of high-performance lithium–sulfur batteries. In this work, we report Rhizopus hyphae biomass carbon (RHBC) as a host material for the sulfur cathode of lithium–sulfur batteries. The porous structure of the RHBC is optimized through hydrothermal activation using KOH solution. The introduction of RHBC into the cathode not only enhances the electronic conductivity of the sulfur cathode, but also substantially improves the capacity of the active materials. Additionally, the RHBC can effectively relieve the volume expansion problem of the sulfur conversion reaction and maintain structural stability, leading to improved lifetime and capacity. Accordingly, the KOH-activated RHBC/S cathode presents initial discharge specific capacity of 748 mAh/g at current density of 0.1 C. Furthermore, the porous structure facilitates rapid transport of electrons and ions, thereby enabling good high-rate performance. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of Cu, Ni, and Zn doping in TiO2 layers on the performance of MAPbI3-based perovskite solar cells (PSCs) fabricated under ambient air with relative humidity between 60% and 70%. One of the factors limiting the efficiency of MAPbI3-based PSCs is the TiO2 electron transport layer properties. The efficiency of PSCs is the maximum power that can be produced by a PSC when illuminated by light with a specific energy. This study aims to enhance MAPbI3-based PSC efficiency by doping TiO2 with 2 mol.% Cu, Ni, and Zn. MAPbI3-based PSCs were then fabricated using spin coating with the structure ITO/TiO2/MAPbI3/graphite/ITO. X-ray diffraction and scanning electron microscopy (SEM) analyses revealed that doping reduced TiO2 crystal sizes from 19.34 nm (pure) to 18.96 nm (Cu-doped), 18.04 nm (Ni-doped), and 17.6 nm (Zn-doped), with corresponding average particle sizes of 225 nm, 107 nm, 79 nm, and 50.4 nm. Ultraviolet–visible (UV–Vis) spectroscopy indicated an increase in the bandgap from 3.0 eV (pure) to 3.1 eV (Cu-doped), 3.2 eV (Ni-doped), and 3.25 eV (Zn-doped). Current–voltage (I–V) electrical testing revealed improvement in efficiency from 5.7% (undoped) to 7.6% (Cu-doped), 6.9% (Ni-doped), and 8.01% (Zn-doped). These findings demonstrate that metal-doped TiO2 significantly enhances the efficiency of MAPbI3-based PSCs fabricated in open-air environments without the need for a glove box. [ABSTRACT FROM AUTHOR]

Although perovskite solar cells (PSCs) have captured notable interest as a potential candidate for third-generation solar cells, due to their favorable optoelectronic properties, cost-effectiveness, and high efficiency, some issues related to device stability and toxicity of the perovskite (PSK) layer hinders the commercial viability of PSCs. The inherent instability of organic PSK halides and the toxicity of Pb has compelled researchers to focus on developing Pb-free all-inorganic PSCs by replacing the organic species with inorganic (Cs+) cations as a safer alternative. In this study, the SCAPS-1D simulator was employed to investigate the cell performances of all-inorganic Pb-free Cs-based PSCs with three different PSK layers (CsGeI3, CsSnI3, and Cs2TiI6) individually, where inorganic ZnO and CuSCN were used as the electron transport layer (ETL) and the hole transport layer (HTL), respectively. The Cs2TiI6-based PSC was found to have the best performance. Then, the defect tolerance level of the PSK layer and the impact of band offset on cell performances were investigated. The optimum values of the conduction band offset (CBO) and the valence band offset (VBO) were found to be 0 eV and between − 0.1 eV and 0 eV, respectively. Moreover, the effect of interface defects at the ETL/PSK and PSK/HTL interfaces on cell performance was also analyzed as a function of CBO and VBO and, for both cases, the interface defect tolerance limit was recorded as 1016 cm−2. This study observed a high rate of recombination for negative values of CBO and VBO at the interfaces. Thus, these findings will guide researchers in developing high-performance PSCs with suitable inorganic Pb-free perovskite and charge transport layers. [ABSTRACT FROM AUTHOR]