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Fast ion beams induce damage to deoxyribonucleic acid (DNA) by chemical products, including secondary electrons, produced from interaction with liquid water in living cells. However, the production process of these chemical products in the Bragg peak region used in particle therapy is not fully understood. To investigate this process, we conducted experiments to evaluate the radiolytic yields produced when a liquid water jet in vacuum is irradiated with MeV-energy carbon beams. We used secondary ion mass spectrometry to measure the products, such as hydronium cations (H3O+) and hydroxyl anions (OH−), produced along with ·OH radicals, which are significant inducers of DNA damage formation. In addition, we simulated the ionization process in liquid water by incident ions and secondary electrons using a Monte Carlo code for radiation transport. Our results showed that secondary electrons, rather than incident ions, are the primary cause of ionization in water. We found that the production yield of H3O+ or OH− was linked to the frequency of ionization by secondary electrons in water, with these electrons having energies between 10.9 and 550 eV. These electrons are responsible for ionizing the outer-shell electrons of water molecules. Finally, we present that the elementary processes contribute to advancing radiation biophysics and biochemistry, which study the formation mechanism of DNA damage. [ABSTRACT FROM AUTHOR]

We evaluated the dissociation of isolated gas-phase nucleobase molecules induced by mega electron volt (MeV)-energy ions to gain fundamental insights into the reactions of nucleobases upon fast ion irradiation. We studied five nucleobase molecules—adenine, guanine, cytosine, thymine, and uracil—as gas-phase targets. We compared the fragmentation patterns obtained from carbon ion impacts with those obtained from proton impacts to clarify the effect of heavy ion irradiation. We also compared the results with electron impact and photoionization results. In addition, we identified several delayed fragmentation pathways by analyzing the correlation between fragment pairs generated from singly and doubly charged intermediate ions. To determine the lifetimes of delayed fragmentation from singly charged intermediate ions, we evaluated the detection efficiencies of the microchannel plate detector for the neutral fragment HCN as a function of kinetic energy using a new methodology. As the first demonstration of this method, we estimated the lifetimes of C5H5N5+ generated by 1.2-MeV C+ and 0.5-MeV H+ collisions to be 0.87 ± 0.43 and 0.67 ± 0.09 µs, respectively. These lifetimes were approximately one order of magnitude longer than those of the doubly charged intermediate ion C5H5N52+. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Potassium ion batteries (PIBs) are of great interest owing to the low cost and abundance of potassium resources, while the sluggish diffusion kinetics of K+ in the electrode materials severely impede their practical applications. Here, self‐hybridized BiOCl0.5Br0.5 with a floral structure is assembled and used as anode for PIBs. Based on the systematic theoretical calculation and experimental analysis, the unbalance of charge distribution between Cl and Br atoms leads to an enhanced built‐in electric field and a larger interlayer spacing, which can enhance the K+ diffusion. Furthermore, the K+ insertion causes the energetic evolution of polar states in the BiOCl0.5Br0.5 crystal framework, where the dynamic correlation between the K+ and the halogen atoms leads to the formation of hole‐like polarons, which significantly improves the K+ diffusion and reaction kinetics during the charging/discharging process, giving important implications to design the electrode materials with high electrochemical performance by engineering the interaction between electronic structure and interface. Therefore, the BiOCl0.5Br0.5 anode obtains an excellent performance of 171 mAh·g–1 at 1 A·g–1 over 2000 cycles in PIBs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Potassium ion batteries (PIBs) are of great interest owing to the low cost and abundance of potassium resources, while the sluggish diffusion kinetics of K+ in the electrode materials severely impede their practical applications. Here, self‐hybridized BiOCl0.5Br0.5 with a floral structure is assembled and used as anode for PIBs. Based on the systematic theoretical calculation and experimental analysis, the unbalance of charge distribution between Cl and Br atoms leads to an enhanced built‐in electric field and a larger interlayer spacing, which can enhance the K+ diffusion. Furthermore, the K+ insertion causes the energetic evolution of polar states in the BiOCl0.5Br0.5 crystal framework, where the dynamic correlation between the K+ and the halogen atoms leads to the formation of hole‐like polarons, which significantly improves the K+ diffusion and reaction kinetics during the charging/discharging process, giving important implications to design the electrode materials with high electrochemical performance by engineering the interaction between electronic structure and interface. Therefore, the BiOCl0.5Br0.5 anode obtains an excellent performance of 171 mAh·g–1 at 1 A·g–1 over 2000 cycles in PIBs. [ABSTRACT FROM AUTHOR]

High‐performance compact capacitive energy storage is vital for many modern application fields, including grid power buffers, electric vehicles, and portable electronics. However, achieving exceptional volumetric performance in supercapacitors is still challenging and requires effective fabrication of electrode films with high ion‐accessible surface area and fast ion diffusion capability while simultaneously maintaining high density. Herein, a facile, efficient, and scalable method is developed for the fabrication of dense, porous, and disordered graphene through spark‐induced disorderly opening of graphene stacks combined with mechanical compression. The obtained disordered graphene achieves a high density of 1.18 g cm−3, sixfold enhanced ion conductivity compared to common laminar graphene, and an ultrahigh volumetric capacitance of 297 F cm−3 in ionic liquid electrolyte. The fabricated stack cells deliver a volumetric energy density of 94.2 Wh L−1 and a power density of 13.7 kW L−1, representing a critical breakthrough in capacitive energy storage. Moreover, the proposed disordered graphene electrodes are assembled into ionogel‐based all‐solid‐state pouch cells with high mechanical stability and multiple optional outputs, demonstrating great potential for flexible energy storage in practical applications. [ABSTRACT FROM AUTHOR]

Artificial membranes with ion‐selective nanochannels for high‐efficiency mono/divalent ion separation are of great significance in water desalination and lithium‐ion extraction, but they remain a great challenge due to the slight physicochemical property differences of various ions. Here, the successful synthesis of two‐dimensional TpEBr‐based covalent organic framework (COF) nanosheets, and the stacking of them as consecutive membranes for efficient mono/divalent ion separation is reported. The obtained COF nanosheet membranes with intrinsic one‐dimensional pores and abundant cationic sites display high permeation rates for monovalent cations (K+, Na+, Li+) of ≈0.1–0.3 mol m−2 h−1, while the value of divalent cations (Ca2+, Mg2+) is two orders of magnitude lower, resulting in an ultrahigh mono/divalent cation separation selectivity up to 130.4, superior to the state‐of‐the‐art ion sieving membranes. Molecular dynamics simulations further confirm that electrostatic interaction controls the confined transport of cations through the cationic COF nanopores, where multivalent cations face i) strong electrostatic repulsion and ii) steric transport hindrance since the large hydrated divalent cations are retarded due to a layer of strongly adsorbed chloride ions at the pore wall, while smaller monovalent cations can swiftly permeate through the nanopores. [ABSTRACT FROM AUTHOR]

Anion‐reinforced solvation structure favors the formation of inorganic‐rich robust electrode‐electrolyte interface, which endows fast ion transport and high strength modulus to enable improved electrochemical performance. However, such a unique solvation structure inevitably injures the ionic conductivity of electrolytes and limits the fast‐charging performance. Herein, a trade‐off in tuning anion‐reinforced solvation structure and high ionic conductivity is realized by the entropy‐assisted hybrid ester‐ether electrolyte. Anion‐reinforced solvation sheath with more anions occupying the inner Na+ shell is constructed by introducing the weakly coordinated ether tetrahydrofuran into the commonly used ester‐based electrolyte, which merits the accelerated desolvation energy and gradient inorganic‐rich electrode‐electrolyte interface. The improved ionic conductivity is attributed to the weakly diverse solvation structures induced by entropy effect. These enable the enhanced rate performance and cycling stability of Prussian blue||hard carbon full cells with high electrode mass loading. More importantly, the practical application of the designed electrolyte was further demonstrated by industry‐level 18650 cylindrical cells. [ABSTRACT FROM AUTHOR]

Carbon anode‐based Li‐ion batteries (LIBs) have been widely used ranging from portable electronics to electric vehicles (EVs). Here a novel carbon material called microzonal carbon is introduced, synthesized from waste hard rubber (WHR), as an anode material for next‐generation LIBs. This material consists of a hybrid carbon structure embedded with short range ordered carbon zones, including expanded graphene sheets and nanopores. Two types of microzonal carbons (M‐5H and M‐10H) are tested in LIBs to unveil their electrochemical performance. The anode fabricated with M‐10H provides a high initial coulombic efficiency (60%), reversible capacity (377 mA h g−1 at 0.13 C), rate capability (275 mA h g−1 at 2.6 C) and cyclic stability (capacity retention of 99% at 0.13 C after 100 cycles). The electrochemical properties of microzonal carbon can be attributed to its unique hybrid carbon structure, facilitating fast ion diffusion, high electronic conductivity, and the ability to form stable interphase. Therefore, this work presents new insights into the electrochemical behavior of microzonal carbon as an anode material in next‐generation LIBs. [ABSTRACT FROM AUTHOR]

MoS2 is widely reported as anode material for sodium‐ion batteries (SIBs). However, its ability to operate effectively across a wide temperature range and at high rates continues to pose fundamental challenges, limiting its further development. Herein, a monolayer Fe‐doped MoS2/N,O‐codoped C overlapping structure is designed and employed as an anode for wide‐temperature‐range SIBs. Fe doping imparts MoS2 electrode with zero bandgap characteristics, an increased interlayer spacing, and low sodium‐ion diffusion energy barriers across wide operation temperatures. Impressively, Fe atoms doped into the MoS2 lattice can be reduced to superparamagnetic Fe0 nanocrystals of ≈2 nm during conversion reactions. In situ magnetometry reveals that these Fe0 nanocrystals can be used as electron acceptor in the formation of space charge zones with Na+, thereby triggering strong spin‐polarized surface capacitance that facilitates fast sodium‐ion storage over a wide temperature range. Consequently, the designed MoS2 electrode demonstrates exceptional fast‐charging capability in half/full cells operating at −40–60 °C. This study provides novel perspectives on the utilization of heteroatom doping strategies in conversion‐type electrode material design and proves the effectiveness of spin‐polarized surface capacitance effect on enhancing sodium‐ion storage over a wide temperature range. [ABSTRACT FROM AUTHOR]

The practical application of solid polymer electrolyte is hindered by the small transference number of Li+, low ionic conductivity and poor interfacial stability, which are seriously determined by the microenvironment in polymer electrolyte. The introduction of functional fillers is an effective solution to these problems. In this work, based on density functional theory (DFT) calculations, it is demonstrated that the anion vacancy of filler can anchor anions of lithium salt, thereby significantly increasing the transference number of Li+ in the electrolyte. Therefore, flower‐like SnS2‐based filler with abundant sulfur vacancies is prepared under the regulation of functionalized carbon dots (CDs). It is worth mentioning that the CDs dotted on the surface of SnS2 have rich organic functional groups, which can serve as the bridging agent to enhance the compatibility of filler and polymer, leading to superior mechanical performance and fast ion transport pathway. Additionally, the in situ formed Li2S/Li3N at the interface of Li metal and electrolyte facilitate the fast Li+ diffusion and uniform Li deposition, effectively mitigating the growth of lithium dendrites. As a result, the assembled lithium metal batteries exhibit excellent cycling stability, reflecting the superiority of the carbon dots derived vacancy‐rich inorganic filler modification strategy. [ABSTRACT FROM AUTHOR]

The lack of stable solid‐state electrolytes (SSEs) with high‐ionic conductivity and the rational design of electrode/electrolyte interfaces remains challenging for solid‐state lithium batteries. Here, for the first time, a high‐performance solid‐state lithium‐oxygen (Li−O2) battery is developed based on the Li‐ion‐conducted hydrogen‐bonded organic framework (LHOF) electrolyte and the HOF‐DAT@CNT composite cathode. Benefiting from the abundant dynamic hydrogen bonding network in the backbone of LHOF‐DAT SSEs, fast Li+ ion transport (2.2×10−4 S cm−1), a high Li+ transference number (0.88), and a wide electrochemical window of 5.05 V are achieved. Symmetric batteries constructed with LHOF‐DAT SSEs exhibit a stably cycled duration of over 1400 h with uniform deposition, which mainly stems from the jumping sites that promote a uniformly high rate of Li+ flux and the hydrogen‐bonding network structure that can relieve the structural changes during Li+ transport. LHOF‐DAT SSEs‐based Li−O2 batteries exhibit high specific capacity (10335 mAh g−1), and stable cycling life up to 150 cycles. Moreover, the solid‐state lithium metal battery with LHOF‐DAT SSEs endow good rate capability (129.6 mAh g−1 at 0.5 C), long‐term discharge/charge stability (210 cycles). The design of LHOF‐DAT SSEs opens an avenue for the development of novel SSEs‐based solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

Developing suitable anode materials to fabricate metal‐free Zinc ion battery is a promising strategy to solve the issues of Zn metal anode, such as dendrite growth and side reactions. However, the reported anode materials face shortcomings such as unsatisfactory rate performance, low mass loading, etc. Herein, featuring synergetic proton‐dominated storage and electron transfer, a conjugated polyimide nanocomposite trapped by multi‐walled carbon nanotubes (PPN‐MWCNT) is developed for high‐loading, fast‐rate organic anode materials in metal‐free Zinc ion battery. Specifically, abundant hydrophilic active sites and nonplaner conjunctional structure in PPN achieve proton‐dominated storage with two steps four electrons mechanism, leading to fast ion diffusion, and the intimate contact between the polymer and MWCNT via in situ polymerization ensures the excellent charge transfer and robust structure. Thus, the PPN‐MWCNT electrode delivers low redox potential, ultrahigh rate performance (50 A g−1), superior loading capability (≈40 mg cm−2) and exceptional long‐term cyclability (over 12 000 cycles). More importantly, the full batteries assembled with PPN‐MWCNT anode and different cathodes deliver a high energy density of 106.4 Wh kg−1 (PPN‐MWCNT//MnO2) and 83.7 Wh kg−1 (PPN‐MWCNT//active carbon‐I2), exceeding the most reported metal‐free Zinc ion batteries. [ABSTRACT FROM AUTHOR]

The two-phase protection layers induce a reinforcement effect on the Zn anode. Specifically, Sb nanoparticles can act as nucleation sites to promote the uniform Zn deposition and homogenize the electric field around the Zn surface. While ZHS micrometer-size sheets possess sufficient electrolyte wettability, fasting ion transfer kinetics and anti-corrosion, and thus guaranteeing uniform ion flux and suppressing dendrite growth and side reactions. [Display omitted] Rechargeable aqueous zinc ion batteries with abundant resources and high safety have gained extensive attention in energy storage technology. However, the cycle stability is largely limited by notorious Zn dendrite growth and water-induced interfacial side reactions. Here, a uniform and robust protection layer consisting of metal antimony (Sb) nanoparticles and micrometer-size sheets Zn 4 (OH) 6 SO 4 ·5H 2 O (ZHS) is purposely designed to stabilize Zn anode via an in situ chemical reaction strategy. The two-phase protection layers (Sb/ZHS) induce a reinforcement effect on the Zn anode (Zn@Sb/ZHS). Specifically, Sb nanoparticles play the part of nucleation sites to facilitate uniform Zn plating and homogenize the electric field around the Zn surface. ZHS micrometer-size sheets possess sufficient electrolyte wettability, fast ion transfer kinetics, and anti-corrosion, thus guaranteeing uniform ion flux and inhibiting H 2 O decomposition. As expected, the symmetric Zn@Sb/ZHS//Zn@Sb/ZHS cells achieve a minimal voltage hysteresis and a reversible cycle of over 2000 h at 1 mA cm−2. By pairing with the MnO 2 cathode, the full cell exhibits a significantly improved stability (∼94.17 % initial capacity after 1500 cycles). This study provides a new strategy to design artificial protection layers. [ABSTRACT FROM AUTHOR]

The recent classification of lithium as a critical raw material surged the research and development (R&D) of post‐lithium batteries (PLBs). The larger cation charge carriers of these PLBs consequently entailed extensive materials R&D for battery components, especially cathode. Prussian Blue (PB) and its analogues (PBAs) have emerged as promising cathode materials for PLBs due to their desirable characteristics, including a three‐dimensional open framework structure that facilitates fast ion diffusion for both monovalent (Li+, Na+, K+) and multivalent (Mg2+, Ca2+, Zn2+, Al3+) ions, stable framework structures, electrochemical tunability, availability of widely used precursors, and ease of synthesis. Our comprehensive review reveals that several challenges are yet to be addressed in employing PBAs as cathode materials for PLBs, viz., vacancies, crystal water, side reactions, and conductivity issues. This review paper provides an exhaustive survey of material development, including the mitigation strategies of the challenges in employing PBAs as cathode materials for advancing PLBs (i. e., sodium‐ion batteries (SIBs), potassium‐ion batteries (KIBs), magnesium‐ion batteries (MIBs), calcium‐ion batteries (CIBs), zinc‐ion batteries (ZIBs), aluminum‐ion batteries (AIBs)) towards commercialization. [ABSTRACT FROM AUTHOR]

The operation of graphite‐based potassium ion batteries (Gr‐PIBs) remains challenging at low temperatures, limited by slow dynamic behavior. Herein, the solvation structure dual‐regulator strategy of electrolyte is proposed for multidimensional improvement of K+ transfer process including ion transfer at both bulk and interface. The designed electrolyte (an amide solvent, 2,2,2‐Trifluoro‐N, N‐dimethylacetamide) with low freezing point and low viscosity as the primary regulator, and a fluorinated solvent (1,1,2,2‐Tetrafluoroethyl‐2,2,3,3‐tetrafluoropropylether) as the secondary regulator provides a flowing environment and low resistive interface for fast ion transfer. As a result, the regulated electrolyte has a low freezing point of −51.9 °C and exhibits a high ionic conductivity of 3.2 mS cm−1 at −20 °C. Based on the solvation structure dual‐regulator, the graphite anode delivered a high capacity of 252 mAh g−1 which is over 85% of room‐temperature capacity, and the capacity retention rate of a full cell at −20 °C is over 80%. These results demonstrate that the solvation structure dual‐regulator can improve the performances of Gr‐PIBs, promoting the development of low‐temperature PIBs and beyond. [ABSTRACT FROM AUTHOR]

Solid-state electrolytes have garnered attention as potential replacements for liquid organic electrolytes in lithium-ion batteries due to their inherent nonflammability and mechanical stability. In this study, the effect of O doping on the transport properties of Li3PS4 solid electrolytes was investigated using ab initio molecular dynamics (AIMD) simulations. The P–O bond is shorter than the P–S bond after O doping, providing more space for Li-ion migration, and making it easier for Li ions to migrate between tetrahedral Li, which was originally somewhat restricted. The diffusion coefficients of Li ions increase in all XYZ directions after doping, with the most significant improvement observed in the Y direction. Radial distribution function and bond length tracking revealed fast Li ion migration, while the PS4 skeleton remained stable. Our results provide insights for the design of solid-state electrolytes through rational doping strategies. [ABSTRACT FROM AUTHOR]

Aqueous Zn metal batteries show promise for large‐scale energy storage but face challenges including dendrite formation, volume changes, and side reactions. This study introduces a novel anti‐swelling supramolecule‐crosslinked hydrogel (SCH) interphase to stabilize Zn metal anodes. The SCH, composed of cyclodextrin molecules crosslinked with polyvinyl alcohol, offers a multifaceted approach to enhance anode stability. It homogenizes ion flux and suppresses Zn dendrite growth by creating well‐defined pathways for Zn2+ movement. The supramolecular structure selectively traps SO42− ions, effectively desolvating Zn2+ and enabling fast ion transportation. Additionally, by disrupting water cluster hydrogen bonds, SCH reduces free water activity, mitigating corrosion at the Zn surface. Electrochemical tests demonstrate the excellent performance of SCH‐Zn, with symmetric cells achieve lifespans of 1800 h at 4 mA cm−2/2 mAh cm−2 and 1100 h at 10 mA cm−2/5 mAh cm−2. Zn||Cu half‐cells maintain 99.7% Coulombic efficiency over 500 cycles, while full cells with polyaniline cathodes exhibit stable cycling for 1500 cycles at 5 A g−1 with no apparent capacity decay. These results highlight the effectiveness of the SCH in stabilizing Zn anodes. This study provides a new interfacial engineering strategy for high‐performance aqueous Zn batteries, potentially accelerating their practical implementation in large‐scale energy storage. [ABSTRACT FROM AUTHOR]

Prussian blue analogues (PBAs) have been widely applied in many fields, especially as cathode materials of sodium‐ion batteries on account of their low cost and open framework for fast ions transport. However, the capacity of reported PBAs has a great distance from its theoretical value. Herein, we proposed that [Fe(CN)6] vacancies are crucial point for the high specific capacity for the first time. The [Fe(CN)6] vacancies may create net electrons and reduce obstacles to ionic transport, which is conducive to rate performance of PBAs by increasing electronic and ionic conductivity to some extent. As a proof of concept, a series of PBAs have been prepared by co‐precipitation method. And then, a novel precipitation conversion method has been designed, by which unique PBAs with a specific quantity of [Fe(CN)6] vacancies was successfully synthesized. Remarkably, the as‐prepared PBAs possessing hierarchical hollow morphology have reached a unprecedent level of high capacity (168 mAh g−1 at 25 mA g−1, close to PBAs' theoretical capacity 170 mAh g−1), high rate performance (90 mAh g−1 at 5 A g−1), and high energy density (over 500 Wh kg−1). [ABSTRACT FROM AUTHOR]

Potassium ion batteries gradually have aroused worldwide interest due to the limited lithium resource. However, the research on the solid‐state potassium‐ion batteries is at its very early stage. The lack of electrolytes with high ionic conductivity and interfacial stability is the major obstacle. In this work, a new phase of potassium carbazolide (KC12H8N, β‐KCZ) is synthesized and expected to be less rigid in the stacking layers than the reported α‐KCZ, indicating weaker cation−π interactions. Upon complexing KCZ with THF, a new type of potassium solid‐state electrolyte is successfully developed (KxCZ‐yTHF), particularly, an optimal composition K0.9CZ‐0.7THF reveals an ionic conductivity as high as 4.2 × 10−4 S cm−1 at 100 °C, which is among the top K+ conductors at this temperature. Furthermore, KxCZ‐yTHF also demonstrates a remarkable electrochemical stability window of 3.1 V, as well as outstanding interfacial stability and compatibility against K2S electrode during a 400‐h electrochemical cycling test. Other advantages of this electrolyte include cold pressing for molding, ease for scaling up, and high safety upon exposure to air. To the best of the knowledge, this is the first report that a potassium organic compound is employed as potassium solid‐state electrolyte. [ABSTRACT FROM AUTHOR]

Energy storage devices operating at low temperatures are plagued by sluggish kinetics, reduced capacity, and notorious dendritic growth. Herein, novel potassium dual‐ion batteries (PDIBs) capable of superior performance at −60 °C, and fabricated by combining MXenes and polytriphenylamine (PTPAn) as the anode and cathode, respectively, are presented. Additionally, the reason for the anomalous kinetics of K+ (faster at low temperature than at room temperature) on the Ti3C2 anode is investigated. Theoretical calculations, crossover experiments, and in situ XRD at room and low temperatures revealed that K+ tends to bind with solvent molecules rather than anions at subzero temperatures, which not only inhibits the participation of PF6− in the formation of the solid electrolyte interphase (SEI), but also guarantees co‐intercalation behavior and suppresses undesirable K+ storage. The advantageous properties at low temperatures endow the Ti3C2 anode with fast K+ kinetics to unlock the outstanding performance of PDIB at ultralow temperatures. The PDIBs exhibit superior rate capability and high capacity retention at −40 °C and −60 °C. Impressively, after charging‐discharging for 20,000 cycles at −60 °C, the PDIB retained 86.7 % of its initial capacity. This study reveals the influence of temperatures on MXenes and offers a unique design for dual‐ion batteries operating at ultralow temperatures. [ABSTRACT FROM AUTHOR]

The vibrational‐translational (VT) excitation of nitrogen molecules led by collisions with fast ions in subauroral ion drifts (SAID) has been conceived as a potential underlying mechanism contributing to the formation of the Strong Thermal Emission Velocity Enhancement (STEVE) phenomenon (Harding et al., 2020, https://doi.org/10.1029/2020gl087102). In this study, we perform quantum calculations of the VT excitation rates of N2 led by fast‐drifting ions, and evaluate the resulting vibrational distribution of N2 with ionospheric/thermospheric parameters expected under intense SAID condition. We conclude that, while the VT energy transfer led by SAID plays a distinguishable role in the vibrational excitation of N2, it is incapable of populating the high vibrational levels to the required concentration (Harding et al., 2020, https://doi.org/10.1029/2020gl087102) to produce adequate nitric oxide density, and in turn the nitrogen‐dioxide continuum intensity, to account for the STEVE brightness. Plain Language Summary: A night sky phenomenon known as STEVE has captured the attention of scientists and citizen scientists in recent years. It is known that STEVE is inherently related to a special process termed "subauroral ion drifts (SAID)", namely a rapid westward drift of plasma in the Earth's ionosphere. It was thus hypothesized that a collision between fast ions and the nitrogen molecules (N2) may cause the kinetic energy of ions being transferred to the internal energy of N2, which can facilitate the chemical reactions leading to STEVE emissions. In this study, we perform quantum calculations of the energy transfer between fast ions and N2 and conclude that, such energy transfer is inefficient under realistic SAID conditions and incapable of accounting for the STEVE emission. Key Points: We perform quantum calculations of the vibrational‐translational (VT) excitation rates of nitrogen molecules (N2) led by fast‐drifting ionsWe calculate the N2 vibrational distribution including VT excitation with ionospheric/thermospheric parameters expected under SAID conditionWe assess that VT excitation led by SAID is unable to provide adequate high‐level excited N2 population to account for the STEVE brightness [ABSTRACT FROM AUTHOR]

Overall urea–water electrolysis has the potential to be employed in the purification of urea-containing wastewater and the production of hydrogen. However, the lack of cost-effective catalysts currently presents a significant obstacle to the further development of this technology. Through a simple template-directed selenium reaction in a novel type of highly active solution, an interface engineering strategy was designed to synthesize hollow CuSe nanocubes as an efficient bifunctional catalyst. The unique hollow CuSe nanocubes exhibit significant catalytic efficiency because of their larger electrolyte contact area and faster ion transport. In 1 M KOH with a 0.5 M urea electrolyte, CuSe/NF required an overpotential of 199 mV for HER and a potential of 1.38 V for UOR to achieve a current density of 10 mA cm−2. It can work stably for 24 h without significant degradation of activity at 10 mA cm−2, showing excellent durability and excellent stability. For overall urea–water electrolysis, it exhibits a remarkable activity with a low cell voltage of 1.61 V at 10 mA cm−2. Consequently, the design strategy of this unique hollow-structured CuSe provides a new insight to improve electrocatalytic performance and stability. [ABSTRACT FROM AUTHOR]

The current driven by neutral beam injection in tokamak is calculated, and the slowing-down distribution function of the fast ion is obtained by the backward Euler iteration method, including the pitch angle scattering collision. This study reveals that when the pitch-angle cosine is small, the trapped fast-ion current significantly contributes to the total driven current, particularly when the neutral beam is injected perpendicularly. In such cases, the current densities of passing and trapped ions are of the same order of magnitude, with the trapped fast-ion current contributing over 10% to the total neutral beam-driven current. This results in a parabolic profile of the total current in the radial direction, promoting the formation of a negative shear equilibrium structure in the core of the tokamak plasma. The numerical approach was validated against the NUBEAM code while considering electron shielding effects and applied to calculate the neutral beam-driven current in multiple tokamaks. The influence of pitch-angle cosine and neutral beam injection power on the driven current was studied at different radial positions. [ABSTRACT FROM AUTHOR]

Here, we present the design and first calibration results of a new single-channel Fast-Ion D-Alpha (FIDA) spectrometer to be employed at the National Spherical Torus Experiment Upgrade (NSTX-U). The Czerny–Turner-type spectrometer uses a custom-designed aspherical lens setup instead of mirrors and achieves excellent spectral resolution, with high photon throughput through a round-to-linear fiber bundle, and camera frame rates around 8.4 kHz. The spectrometer uses a blocking bar to avoid saturation effects of the cold D-alpha emission line and will allow for detailed studies of the fast-ion confinement in NSTX-U. Expected synthetic spectra predicted with the TRANSP and FIDASIM codes show that the spectral range from 648.5 to 658 nm will sufficiently cover halo, the red-shifted beam emission, and the blue-shifted portion of FIDA emission in NSTX-U, which is sufficient for fast-ion transport studies of co-rotating fast ions. [ABSTRACT FROM AUTHOR]

A set of nonlinear simulations has been performed in order to study the nonlinear evolution of unstable global Alfvén eigenmodes in the National Spherical Torus Experiment-Upgrade (NSTX-U). Results of the single toroidal mode number, n, simulations are compared with a full nonlinear simulation (all toroidal harmonics included). In single-n simulations, the conservation of two integrals of motion of a particle in a cyclotron resonance with a monochromatic wave is demonstrated, resulting in a one-dimensional evolution of the particle distribution in (E , μ , p ϕ ) phase-space. Nonlinear simulations (both single-n and full nonlinear) show a significant redistribution of the resonant fast ions, especially in the pitch parameter. Thus, the changes in the resonant particle's parallel and perpendicular energies can be several times larger than the total particle energy change, with only a small fraction transferring into the excitation of the mode itself. This implies that even a relatively small amplitude mode can significantly modify the beam distribution in the resonant region. For the NSTX-U case considered, the single-n simulation results are close to full nonlinear simulation only for the most unstable mode, in which case the saturation amplitudes and changes in the fast ion distribution are comparable. In contrast, peak amplitudes of subdominant modes in all-n simulations are smaller by a factor of 3–10 compared to single-n runs due to the flattening of the beam ion distribution by the fastest growing mode. [ABSTRACT FROM AUTHOR]

All‐solid‐state potassium batteries emerge as promising alternatives to lithium batteries, leveraging their high natural abundance and cost‐effectiveness. Developing potassium solid electrolytes (SEs) with high room‐temperature ionic conductivity is critical for realizing efficient potassium batteries. In this study, we present the synthesis of K2.98Sb0.91S3.53Cl0.47, showcasing a room‐temperature ionic conductivity of 0.32 mS/cm and a low activation energy of 0.26 eV. This represents an increase of over two orders of magnitude compared to the parent compound K3SbS4, marking the highest reported ionic conductivity for non‐oxide potassium SEs. Solid‐state 39K magic‐angle‐spinning nuclear magnetic resonance on K2.98Sb0.91S3.53Cl0.47 reveals an increased population of mobile K+ ions with fast dynamics. Ab initio molecular dynamics (AIMD) simulations further confirm a delocalized K+ density and significantly enhanced K+ diffusion. This work demonstrates diversification of the anion sublattice as an effective approach to enhance ion transport and highlights K2.98Sb0.91S3.53Cl0.47 as a promising SE for all‐solid‐state potassium batteries. [ABSTRACT FROM AUTHOR]

Designing a nanofluidic membrane with high selectivity and fast ion transport property is the key towards high‐performance osmotic energy conversion. However, most of reported membranes can produce power density less than commercial benchmark (5 W/m2), due to the imbalance between ion selectivity and permeability. Here, we report a novel nanoarchitectured design of a heterogeneous membrane with an ultrathin and dense zirconium‐based UiO‐66‐NH2 metal–organic framework (MOF) layer and a highly aligned and interconnected branched alumina nanochannel membrane. The design leads to a continuous trilayered pore structure of large geometry gradient in the sequence from angstrom‐scale to nano‐scale to sub‐microscale, which enables the enhanced directional ion transport, and the angstrom‐sized (~6.6–7 Å) UiO‐66‐NH2 windows render the membrane with high ion selectivity. Consequently, the novel heterogeneous membrane can achieve a high‐performance power of ~8 W/m2 by mixing synthetic seawater and river water. The power density can be largely upgraded to an ultrahigh ~17.1 W/m2 along with ~48.5 % conversion efficiency at a 50‐fold KCl gradient. This work not only presents a new membrane design approach but also showcases the great potential of employing the zirconium‐based MOF channels as ion‐channel‐mimetic membranes for highly efficient blue energy harvesting. [ABSTRACT FROM AUTHOR]

Nanofluidic energy harvesting from salinity gradients is studied in 2D nanomaterials‐based membranes with promising performance as high ion selectivity and fast ion transport. In addition, moving forward to scalable, feasible systems requires environmentally friendly materials to make the application sustainable. Clay‐based membranes are attractive for being environmentally friendly, non‐hazardous, and easy to manipulate materials. However, achieving underwater stability for clay‐based membranes remains challenging. In this work, the synthetic clay Laponite is used to prepare clay‐based membranes with high stability and excellent performance for osmotic energy harvesting. The Laponite membranes (Lap‐membranes) are stabilized by low‐temperature annealing treatment to effectively reduce the interlayer space, achieving a continuous operation under salinity gradients. Furthermore, the Lap‐membranes conserve integrity while soaking in water for more than one month. The output power density improves from ≈4.97 W m−2 on the pristine membrane to ≈9.89 W m−2 in the membrane treated 12 h at 300 °C from a 30‐fold concentration gradient. Especially, It is found that the presence of interlayer water to be favorable for ion transport. Different mechanisms are proposed in the Lap‐membranes involved for efficient ion selectivity and the states found with varying annealing temperatures. This work demonstrates the potential application of Laponite based nanomaterials for nanofluidic energy harvesting. [ABSTRACT FROM AUTHOR]

The scalable fabrication of cost-efficient bifunctional catalysts with enhanced hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance plays a significant role in overall water splitting in hydrogen production fields. MoSe2 is considered to be one of the most promising candidates because of its low cost and high catalytic activity. Herein, hierarchical nitrogen-doped carbon networks were constructed to enhance the catalytic activity of the MoSe2-based materials by scalable free-drying combined with an in situ selenization strategy. The rationally designed carbonaceous network-encapsulated MoSe2 composite (MoSe2/NC) endows a continuous honeycomb-like structure. When utilized as a bifunctional electrocatalyst for both HER and OER, the MoSe2/NC electrode exhibits excellent electrochemical performance. Significantly, the MoSe2/NC‖MoSe2/NC cells require a mere 1.5 V to reach a current density of 10 mA cm−2 for overall water splitting in 1 M KOH. Ex situ characterizations and electrochemical kinetic analysis reveal that the superior catalytic performance of the MoSe2/NC composite is mainly attributed to fast electron and ion transportation and good structural stability, which is derived from the abundant active sites and excellent structural flexibility of the honeycomb-like carbon network. This work offers a promising pathway to the scalable fabrication of advanced non-noble bifunctional electrodes for highly efficient hydrogen evolution. [ABSTRACT FROM AUTHOR]

Biomass‐based hard carbon has the advantages of a balanced cost and electrochemical performance, making it the most promising anode material for sodium‐ion batteries. However, due to the structural limitations of biomass (such as macropores and impurities), it still faces the problems of low specific capacity and initial Coulombic efficiency (ICE). Herein, an integrated strategy of biomass liquefaction and oxidation treatment is proposed to fabricate hard carbon with low ash content and sp2‐rich closed pores. Specifically, liquefaction treatment can break through the inherent constraints of biomass, while oxidation treatment with O‐targeted effect can directionally convert C─C/C─O bonds into C═O/O═C─O bonds, which would promote the formation of closed pores and the rearrangement into sp2‐carbon within the graphene layer. Moreover, it is well demonstrated that the hard carbon interface rich in sp2 hybridization can induce the generation of an inorganic‐rich solid electrolyte interface, contributing to fast ion migration and excellent interfacial stability. As a result, the optimized hard carbon with maximum closed pore volume and sp2/sp3 ratio can exhibit a high capacity of 347.3 mAh g−1 at 20 mA g−1 with the ICE of 90.5%, and a capacity of 110.4 mAh g−1 at 5.0 A g−1 after 10 000 cycles. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) has been recognized as an ideal anode material for fast‐charging lithium (Li)‐ion capacitors (LICs) due to its high theoretical capacity (2596 mAh g−1), appropriate lithiation potential (0.7 V vs Li+/Li) and fast ion diffusion capability. However, large volume change and soluble polyphosphides (LixPs)‐based intermediates during charging‐discharging process seriously deteriorate cycling performance. To address the aforementioned issues, an elaborated design is reported on the binder for BP electrode. The ‐NH2 polar functional group in grafted chitosan (GCS) binder presents strong chemical anchoring effect for both BP and soluble LixPs, achieving superior adhesion force and LixPs constraining capability for enhanced structure integrity of BP electrode. In addition, GCS exhibits strong Li‐ion binding energy that promotes the Li‐ion adsorption at electrode level, leading to a boosted cycle life for BP. As a result, the graphene (G) incorporated BP electrode using GCS binder shows specific capacity of 997.6 mAh g−1 after 400 cycles at 1 A g−1. This study unravels the crucial role of functional groups for binder in high‐performance BP electrode. [ABSTRACT FROM AUTHOR]

Porous hard carbon with good cycling durability attracts much attention in the application of sodium ions batteries as anode material, but the commonly used alkali metal ion-activation strategy with complex processes still renders its development. Herein, a simple and scalable method is proposed to synthesize hierarchical porous hard carbon. Benefitting from the efficient self-activation strategy, the hierarchical micro–mesoporous hard carbon (MMHC) with large interlayer distance possesses high specific surface area of 704.1 m2 g−1, which can provide shorter ionic diffusion path and much more accessible electrochemical active sites in the carbonaceous structure and then lead to fast sodium ion diffusivity kinetics (3.5 × 10–9 cm2 s−1). In consequence, MMHC electrode delivers high specific capacity of 214.3 mAh g−1 at 50 mA g−1, 118.3 mAh g−1 at 500 mA g−1 after 1000 cycles and 47.4 mAh g−1 even at 4000 mA g−1. Notably, the capacity contribution ratio from low-voltage range is enhanced with engineering micro–mesoporous structure (from 28.5% for HC to 37.7% for MMHC). Promisingly, the hierarchical micro–mesoporous hard carbon holds great potential in commercial sodium ions batteries. [ABSTRACT FROM AUTHOR]

A novel Imaging Neutral Particle Analyzer (INPA) was newly installed in early 2024 to enhance the understanding of fast ion confinement on Large Helical Devices (LHDs). This diagnostic system, based on a magnetic spectrometer using a scintillator, provides energy-resolved radial profiles of confined fast ions by measuring charge-exchanged fast neutrals escaping from the plasma. The system utilizes a 100 nm thick carbon foil to ionize the fast neutrals, subsequently deflecting the ions toward a scintillator via the existing local magnetic field. The fast ion energy and sightline determine the position of the scintillation, while the light intensity depends on the flux of the fast ions. The INPA features two apertures, facilitating effective measurements in both clockwise and counterclockwise magnetic field directions in the LHD. This INPA was designed as a passive measurement system that measures fast ions charge exchange with background neutrals, focusing on perpendicular beam ions from 5 to 100 keV with an energy resolution of about 5.75 keV. This paper describes the details of the design, installation, and the initial results of the INPA on the LHD. This work will contribute significantly to a deeper understanding of fast ion transport due to magnetohydrodynamic instabilities. [ABSTRACT FROM AUTHOR]

A set of new millimeter-wave diagnostics will deliver unique measurement capabilities for National Spherical Torus Experiment-Upgrade to address a variety of plasma instabilities believed to be important in determining thermal and particle transport, such as micro-tearing, global Alfvén eigenmodes, kinetic ballooning, trapped electron, and electron temperature gradient modes. These diagnostics include a new integrated intermediate-k Doppler backscattering (DBS) and cross-polarization scattering (CPS) system (four channels, 82.5–87 GHz) to measure density and magnetic fluctuations, respectively. The system can access reasonably large normalized wavenumbers kθρs ranging from ≤0.5 to 15 (where ion sound gyroradius ρs = 1 cm and kθ is the binormal density turbulence wavenumber). The system addresses the challenges for making useful DBS/CPS measurements with a remote control of launch polarization (X- or O-mode), probed wavenumber, polarization match of the launch beam with the edge magnetic field pitch angle, and beam steering of the launched beam for wave-vector alignment. In addition, a low-k DBS system consisting of eight fixed frequencies (34–52 GHz) and four tunable frequencies (55–75 GHz) for low-k density turbulence and fast ion physics will be located at a nearby port location. The combined systems cover the near LCFS and pedestal regions (34–52 GHz), the pedestal or mid-radius (50–75 GHz), and core plasmas (82.5–87 GHz). [ABSTRACT FROM AUTHOR]

[Display omitted] • The electrochemical properties of BG are significantly enhanced by the morphology of the constructed wool-like clusters. • The optimized BG-2 exhibits excellent rate performance and cycling stability. • The appropriate iron content in 3D skeletons opens a new possibility for enhancing ammonium ion storage. Prussian blue analogues (PBAs) are regarded as promising cathode materials for ammonium-ion batteries (AIBs) because of their low cost and superb theoretical capacity. However, its inherently poor conductivity and structural collapse can significantly limit the enhancement of rate property and cycling stability. In this work, Berlin Green (BG) electrode materials with similar wool-like clusters were constructed by direct precipitation method to accelerate the kinetic, which realizes outstanding cycling stability. Berlin Green with the appropriate amount of iron (BG-2) has a fast ion transport channel, enhanced structure stability, highly reversible insertion/extraction of NH 4 +, and fine electrochemical reaction activity. Benefiting from the unique architecture and component, the BG-2 electrode shows an excellent rate performance with a discharge/charge specific capacity of 60.1/59.3 mAh g−1 at 5 A g−1. Even at 5 A g−1, BG-2 exhibits remarkable cycling stability with an initial discharge capacity of 59.5 mAh g−1 and a capacity retention rate of approximately 76% after 30,000 cycles. The BG-2 reveals exceedingly good electrochemical reversibility during the process of NH 4 + (de)insertion. BG materials indicate huge potential as a cathode material for the next generation of high-performance aqueous batteries. [ABSTRACT FROM AUTHOR]

Iron-based hexacyanoferrate (Fe-HCF) are promising cathode materials for sodium-ion batteries (SIBs) due to their unique open-channel structure that facilitates fast ion transport and framework stability. However, practical implementation of SIBs has been hindered by low initial Coulombic efficiency (ICE), poor rate performance, and short lifespan. Herein, we report a coordination engineering to synthesize sodium-rich Fe-HCF as cathodes for SIBs through a uniquely designed 10-kg-scale chemical reactor. Our study systematically investigated the relationship between coordination surroundings and the electrochemical behavior. Building on this understanding, the cathode delivered a reversible capacity of 99.3 mAh g-1 at 5 C (1 C = 100 mA g-1), exceptional rate capability (51 mAh g-1 even at 100 C), long lifespan (over 15,000 times at 50 C), and a high ICE of 92.7%. A full cell comprising the Fe-HCF cathode and hard carbon (HC) anode exhibited an impressive cyclic stability with a high-capacity retention rate of 98.3% over 1,000 cycles. Meanwhile, this material can be readily scaled to the practical levels of yield. The findings underscore the potential of Fe-HCF as cathodes for SIBs and highlight the significance of controlling nucleation and morphology through coordination engineering for a sustainable energy storage system. [ABSTRACT FROM AUTHOR]

Pt2Ca nanoparticles with a mean size diameter of 6 nm can be prepared by heating K2PtCl6, CaH2, carbon black and KCl at 400–500 °C. A mechanism study suggests that the formation of the Pt2Ca phase at moderate temperature is enabled by the fast ion transport via the vacancies in the KCl–CaH2 solid solution. The Pt2Ca nanoparticles exhibit high performance for the oxygen reduction reaction in acid due to optimal adsorption energy of the oxygen intermediate. [ABSTRACT FROM AUTHOR]

Rechargeable multivalent‐ion batteries are attractive alternatives to Li‐ion batteries to mitigate their issues with metal resources and metal anodes. However, many challenges remain before they can be practically used due to the low solid‐state mobility of multivalent ions. In this study, a promising material identified by high‐throughput computational screening is investigated, ε‐VOPO4, as a Mg cathode. The experimental and computational evaluation of ε‐VOPO4 suggests that it may provide an energy density of >200 Wh kg−1 based on the average voltage of a complete cycle, significantly more than that of well‐known Chevrel compounds. Furthermore, this study finds that Mg‐ion diffusion can be enhanced by co‐intercalation of Li or Na, pointing at interesting correlation dynamics of slow and fast ions. [ABSTRACT FROM AUTHOR]

Li‐rich antiperovskite (LiRAP) hydroxyhalides are emerging as attractive solid electrolyte (SEs) for all‐solid‐state Li metal batteries (ASSLMBs) due to their low melting point, low cost, and ease of scaling‐up. The incorporation of rotational polyanions can reduce the activation energy and thus improve the Li ion conductivity of SEs. Herein, we propose a ternary rotational polyanion coupling strategy to fasten the Li ion conduction in tetrafluoroborate (BF4−) ion doped LiRAP Li2OHCl. Assisted by first‐principles calculation, powder X‐ray diffraction, solid‐state magnetic resonance and electrochemical impedance spectra, it is confirmed that Li ion transport in BF4− ion doped Li2OHCl is strongly associated with the rotational coupling among OH−, BF4− and Li2−O−H octahedrons, which enhances the Li ion conductivity for more than 1.8 times with the activation energy lowering 0.03 eV. This work provides a new perspective to design high‐performance superionic conductors with multi‐polyanions. [ABSTRACT FROM AUTHOR]

MoS2 nanosheets consist of multiple S-Mo-S trilayers with large interlayer spacing, which could allow facile Li-ion insertion/extraction. However, MoS2 nanosheets are easily curled and randomly stacked due to high surface energy of 2D nanosheets, which hinders fast ion transportation. In addition, intrinsic electronic conductivity of MoS2 is limited. Therefore, enhancements of both ionic and electronic conductivity of MoS2 are greatly demanded for its application in Li-ion batteries. Here, we report a cost-effective and facile hydrothermal synthesis of 3D nanoflower-like MoS2/C anode materials, which avoids random stacking of nanosheets and improves the electronic conductivity of MoS2. The nanoflower-like MoS2/C exhibits large reversible specific capacity (724 mAh g−1) and high initial coulombic efficiency (79.82%). Moreover, excellent capacity retention (97.98%) after 500-cycle charge/discharge has been achieved at 1 A g−1. [ABSTRACT FROM AUTHOR]

The loss of ion cyclotron resonance frequencies (ICRF)-heated neutral beam injection ions in experimental advanced superconducting tokamak was numerically investigated by ORBIT code simulations. The effects of collisions and ripples on particle losses were taken into account, and the distributions of fast ions generated by different beams in combination with ICRF heating were calculated using the TRANSP code. Results showed that ICRF waves altered the orbital distributions of beam ions, causing an increase in trapped ions and fast ion losses. Additionally, for co-current injected beams, perpendicular injection resulted in higher fast ion losses in synergistic heating than tangential injection. The study also found that the synergistic effect of collisions and ripples enhanced fast ion losses, which were highly localized and generated a maximum heat load of 0.165 MW m−2 on the first wall. However, conducting synergy heating experiments at high plasma currents and low effective ion charge numbers can significantly reduce the loss of fast ions. [ABSTRACT FROM AUTHOR]

Zinc-ion capacitors (ZICs), combining the merits of both high-energy zinc-ion batteries and high-power supercapacitors, are known as high-potential electrochemical energy storage (EES) devices. However, the research on ZICs still faces many challenges because of the lack of appropriate cathode materials with robust crystal structures and rich channels for stable and fast Zn2+ ion transport. In this study, we synthesized a robust, conductive, two-dimensional metal–organic framework (MOF) material, zinc-benzenehexathiolate (Zn-BHT), and investigated its electrochemical performance for zinc storage. Zn2+ ions could insert into/extricate from the host structure with a high diffusion rate, enabling the Zn-BHT cathode to exhibit a surface-controlled charge storage mechanism. Due to its unique structure, Zn-BHT exhibited a good reversible discharge capacity approaching 90.4 mAh g−1 at 0.1 A g−1, as well as a desirable rate capability and good cycling performance. In addition, a ZIC device was fabricated using the Zn-BHT cathode and a polyaniline-derived porous carbon (PC) anode, which depicted a high working voltage of up to 1.8 V and a high energy density of ~37.2 Wh kg−1. This work shows that conductive MOFs are high-potential electrode materials for ZICs and provide new enlightenment for the development of electrode materials for EES devices. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive crystalline materials have received much attention for being potential candidates of smart materials. However, the occurrence of polymorphism‐driven stimuli responses in crystalline materials remains interesting but rare. Herein, three polymorphs of an acylhydrazone derivative, N′‐[(E)‐(1‐benzofuran‐2‐yl) methylidene] pyridine −4‐carbohydrazide (BFMP) were prepared. Form‐1 undergoes a photomechanical response via E→Z photoisomerization under UV irradiation, accompanied by a decrease in fluorescence intensity and a change from colorless to yellow. Two types of Z→E thermal isomerization mechanisms with significant differences in conversion rate were observed at different temperatures in form‐1. The solid‐melt‐solid transition has a faster conversion rate compared to the solid‐solid transition due to freedom from lattice confinement. The transition from form‐2 to form‐3 can be achieved under grinding, coupled with a significant decrease in fluorescence intensity. The similar molecular stacking pattern of form‐2 and form‐3 provides a structural basis for the grinding‐induced crystalline transition behavior. In addition, the presence of the pyridine moiety imparts an acidochromic property. The combination of photochromism and acidochromism explores the possible applications of acylhydrazone derivatives in information encryption. [ABSTRACT FROM AUTHOR]

The low‐voltage charging capacity and rate performance are two crucial but mutually restricted properties of K‐ion batteries. Herein, a sulfonamide and amide linkages‐triggered N doping high‐temperature removal strategy is proposed to obtain porous carbon with rich carbon vacancies, high sp2 hybridized C content (65.3%), and large interlayer spacing using coal tar pitch as carbon precursor. Carbon vacancies and sp2 hybridized C are proved to be not only active sites for low‐voltage potassium storage but also conducive to the fast transfer of ions and electrons, endowing reversible and fast potassium storage at low voltage. Moreover, abundant carbon vacancies and large carbon interlayer spacing alleviate volume variation, improving the cycling stability for 8500 cycles (about 3700 h). This work sheds new light on the design of low‐voltage, durable, and fast potassium storage carbon anodes, and promotes the development of practical carbon anodes for high energy density K‐ion batteries in the future. [ABSTRACT FROM AUTHOR]

This work reviews the progression of chemical analysis via Cherenkov emissions, i.e., Cherenkov Photometry and Cherenkov Emission Spectroscopy, from its introduction in the literature up to modern developments. In presenting the history of this field, we aim to consolidate the literature, both for reference and contextualization. We present an argument aiming to untangle why this corner of research has seen little progress while so many other directly related aspects of Cherenkov research have flourished, as well as speak to the progress of the field in recent years and prospective direction in years to come. [ABSTRACT FROM AUTHOR]

Iron sulfide (FeS) has been extensively studied as sodium‐ion battery anodes due to its high theoretical capacity (609 mAh g−1), but its large volume expansion and low electrical conductivity result in unsatisfactory cycling life and poor rate performance. Moreover, the sodium ion storage mechanism of FeS at a voltage range of 0.01–1 V involving conversion reactions and subsequent ion storage process is unclear yet. Here, the study proposes a vapor‐pressure induced synthesis route to fabricate FeS/C yolk‐shell structure that ultrathin carbon layers coat on the surface of FeS nanosheets, which can accommodate volume expansion of FeS during sodiation observed via in situ transmission electron microscope and improve its electrical conductivity. Remarkably, an in situ magnetometry reveals that vast spin‐polarized electrons can be injected into superparamagnetic Fe nanoparticles (≈3 nm) formed during conversion reaction to induce evolution of electrode magnetization between 0.01 and 1 V, during which spin‐polarized surface capacitance effect occurs at Fe/Na2S interfaces to increase extra ion storage and boost ion transport stably. Consequently, the FeS/C yolk‐shell nanosheets deliver a high reversible capacity of 664.9 mAh g−1 at 0.1 A g−1, and 300.4 mAh g−1 after 10 000 cycles at 10 A g−1 with a capacity retention of 81.1%. [ABSTRACT FROM AUTHOR]

Anion‐derived solid‐electrolyte interphase (SEI) has received growing attention owing to its appealing properties like fast ion transport and excellent passivation effect. However, a sophisticated understanding of anion‐derived SEI is lacking. To common wisdom, anion‐derived SEI features an inorganic‐rich composition. Herein, it is reveal that the freshly formed anion‐derived SEI consists of a polymer‐rich outer layer and an inorganic inner layer. Then, the organic components dissolve during the discharge process, while the inorganic species with low solubility are retained in the empty SEI husk. The accumulation of empty SEI husks during cycling forms a reacted lithium (Li) layer, which features a much higher content of anion‐derived inorganic species than the newly formed SEI. Therefore, the acknowledged "anion‐derived inorganic‐rich SEI" actually refers to the reacted Li layer instead of the freshly formed SEI. This work provides fruitful insights on the compositional features of anion‐derived SEI. [ABSTRACT FROM AUTHOR]

Calcium‐ion batteries (CIBs) are considered as potential next‐generation energy storage systems due to their abundant reserves and relatively low cost. However, irreversible structural changes and weak conductivity still hinder in current CIBs cathode materials. Herein, an organic molecular intercalation strategy is proposed, in which V2O5 regulated with quinoline, pyridine, and water molecules are studied as cathode material to provide fast ion diffusion channels, large storage host, and high conductivity for Ca ions. Among them, V2O5‐quinoline (QVO) owns the largest interplanar spacing of 1.25 nm and the V‐O chains are connected with organic molecular by hydrogen bond, which stabilizes the crystal structure. As a result, QVO exhibits a specific capacity of 168 mAh g−1 at 1 A g−1 and capacity retention of 80% after 500 cycles at 5 A g−1 than the other materials. Furthermore, X‐Ray diffraction and X‐ray absorption spectroscopy results reveal a reversible order‐disorder transformation mechanism of Ca2+ for QVO, which can make full use of the abundant active sites for high capacity and simultaneously achieve fast reaction kinetics for excellent rate performance. These results demonstrate that QVO is a promising cathode material for CIBs, providing more choices for the development of high‐performance CIBs. [ABSTRACT FROM AUTHOR]

To measure the high-energy part of the energy distribution function of ions in a hot plasma using the pellet charge exchange (PCX) diagnostic, it is necessary to know the energy dependence of the fraction F0(E) of fast ions neutralized when intersecting a pellet cloud. Using experimental and calculated data on the ablation of polystyrene macroparticles (pellets) in the LHD stellarator, the function F0(E) for protons in the hydrocarbon cloud has been calculated in the energy range of 50–1000 keV at pitch angles . At energies of 50‒200 keV, it is necessary to take into account the decrease in the flux of neutralized protons multiply intersecting the cloud. Energy losses of protons along the trajectory provide a lower bound E > 100 keV for the possible PCX measurements. The necessity of the control of the charge state composition and structure of the cloud limits the view area of the detector of atoms within ±30 mm from the position of a pellet along the magnetic field. For this reason, the injection axis should be aligned with the observation axis of the neutral particle analyzer for the optimal geometry of PCX measurements with polystyrene pellets. [ABSTRACT FROM AUTHOR]

The precise controllability of the Fermi level is a critical aspect of quantum materials. For topological Weyl semimetals, there is a pressing need to fine-tune the Fermi level to the Weyl nodes and unlock exotic electronic and optoelectronic effects associated with the divergent Berry curvature. However, in contrast to two-dimensional materials, where the Fermi level can be controlled through various techniques, the situation for bulk crystals beyond laborious chemical doping poses significant challenges. Here, we report the milli-electron-volt (meV) level ultra-fine-tuning of the Fermi level of bulk topological Weyl semimetal tantalum phosphide using accelerator-based high-energy hydrogen implantation and theory-driven planning. By calculating the desired carrier density and controlling the accelerator profiles, the Fermi level can be experimentally fine-tuned from 5 meV below, to 3.8 meV below, to 3.2 meV above the Weyl nodes. High-resolution transmission electron microscopy reveals the crystalline structure is largely maintained under irradiation, while electrical transport indicates that Weyl nodes are preserved and carrier mobility is also largely retained. Our work demonstrates the viability of this generic approach to tune the Fermi level in semimetal systems and could serve to achieve property fine-tuning for other bulk quantum materials with ultrahigh precision. [ABSTRACT FROM AUTHOR]