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In aqueous aluminum‐ion batteries (AAIBs), the insertion/extraction chemistry of Al3+ often leads to poor kinetics, whereas the rapid diffusion kinetics of hydronium ions (H3O+) may offer the solution. However, the presence of considerable Al3+ in the electrolyte hinders the insertion reaction of H3O+. Herein, we report how oxygen‐deficient α‐MoO3 nanosheets unlock selective H3O+ insertion in a mild aluminum‐ion electrolyte. The abundant oxygen defects impede the insertion of Al3+ due to excessively strong adsorption, while allowing H3O+ to be inserted/diffused through the Grotthuss proton conduction mechanism. This research advances our understanding of the mechanism behind selective H3O+ insertion in mild electrolytes. [ABSTRACT FROM AUTHOR]

Decreasing perovskite nanocrystal size increases radiative recombination due to the quantum confinement effect, but also increases the Auger recombination rate which leads to carrier imbalance in the emitting layers of electroluminescent devices. Here, we overcome this trade‐off by increasing the exciton effective mass without affecting the size, which is realized through the trace Cd2+ doping of formamidinium lead bromide perovskite nanocrystals. We observe an ~2.7 times increase in the exciton binding energy benefiting from a slight distortion of the [BX6]4− octahedra caused by doping in the case of that the Auger recombination rate is almost unchanged. As a result, bright color‐saturated green emitting perovskite nanocrystals with a photoluminescence quantum yield of 96 % are obtained. Cd2+ doping also shifts up the energy levels of the nanocrystals, relative to the Fermi level so that heavily n‐doped emitters convert into only slightly n‐doped ones; this boosts the charge injection efficiency of the corresponding light‐emitting diodes. The light‐emitting devices based on those nanocrystals reached a high external quantum efficiency of 29.4 % corresponding to a current efficiency of 123 cd A−1, and showed dramatically improved device lifetime, with a narrow bandwidth of 22 nm and Commission Internationale de I'Eclairage coordinates of (0.20, 0.76) for color‐saturated green emission for the electroluminescence peak centered at 534 nm, thus being fully compliant with the latest standard for wide color gamut displays. [ABSTRACT FROM AUTHOR]

Developing effective strategy to passivate surface defects in quantum dots (QDs) is critical to achieving high‐efficiency and long‐life perovskite light‐emitting diodes (LEDs). Here, the supramolecular interaction underpinning of organic‐inorganic components is exploited and a facile method is proposed to generate multiple‐hydrogen‐bonded supramolecular‐perovskite crystal structures on QD surfaces by introducing O‐Tolylbiguanide (O‐Tg) during QD synthesis, enabling bright, conductive, and water‐resistant CsPbI3 QDs. Compared with commonly used oleic acid and oleylamine ligands, the biguanide functional group in O‐Tg not only forms multiple hydrogen bond interactions with lead halide octahedra passivating both bridging‐ and terminal‐halogen ion defects, but also compatibly occupies the A‐site position stabilizing the crystal structure simultaneously. With fewer nonradiative defects and introduced hydrophobic benzene rings preventing eroding of polar molecules, CsPbI3 QDs exhibit remarkable photoluminescence quantum yields of 96%, and their film can be submerged in water for 30 h without degrading. The corresponding LEDs display a high external quantum efficiency (21.2%) and offer superior operational stability with a lifetime (T90) of 25 h at a constant current density as high as 50 mA cm−2. [ABSTRACT FROM AUTHOR]

There is considerable interest in the potential of stereotactic body radiation therapy (SBRT) combined with systemic therapy such as tyrosine kinase inhibitors (TKIs) or immune checkpoint inhibitors (ICIs). However, its efficacy and safety remain unclear. The purpose of this study was to evaluate the efficacy and safety of conducting SBRT during ICI or TKI treatment in different disease settings for patients with metastatic renal cell carcinoma (mRCC). A total of 16 studies were ultimately included. Under the random effects model, the pooled 1‐year local control rate (1‐yr LCR) and objective response rate (ORR) were 90% (95% confidence interval [CI]: 80%–95%, I2 = 67%) and 52% (95% CI: 37%–67%, I2 = 90%), respectively. SBRT concomitant with different systemic therapy yield significant different 1‐yr LCR (p < 0.01) and ORR (p = 0.02). Regarding survival benefits, the pooled 1‐year progression‐free survival (1‐yr PFS) and 1‐year overall survival (1‐yr OS) rates were 45% (95% CI: 29%–62%, I2 = 91%) and 85% (95% CI: 76%–91%, I2 = 66%), respectively. 1‐yr PFS and 1‐yr OS in different disease settings demonstrated significant difference (p < 0.01). As for toxicity, the pooled incidence of grade 3–4 adverse events was 14% (95% CI: 5%–26%, I2 = 90%). This study highlights the feasibility of utilizing these strategies in mRCC patients, especially those with a low metastatic tumor burden. [ABSTRACT FROM AUTHOR]

Zero‐dimensional lead halide perovskite nanocrystals (NCs) exhibit size‐dependent bandgap and carrier confinement compared to bulk counterparts due to the quantum confinement effect, making them essential for achieving wide‐color‐gamut displays, studying excitonic spin relaxation, and constructing superlattices. Despite their promising potential, they face a variety of technical bottlenecks, such as insufficient color reproducibility, limited large‐scale production, low stability, and toxicity. An outline of a research roadmap is provided in the review, which highlights key challenges in developing perovskite NCs for commercial applications. [ABSTRACT FROM AUTHOR]

Metal single‐atom catalysts represent one of the most promising non‐noble metal catalysts for the oxygen reduction reaction (ORR). However, they still suffer from insufficient activity and, particularly, durability for practical applications. Leveraging density functional theory (DFT) and machine learning (ML), we unravel an unexpected collective effect between FeN4OH sites, CeN4OH motifs, Fe nanoparticles (NPs), and Fe−CeO2 NPs. The collective effect comprises differently‐weighted electronic and geometric interactions, whitch results in significantly enhanced ORR activity for FeN4OH active sites with a half‐wave potential (E1/2) of 0.948 V versus the reversible hydrogen electrode (VRHE) in alkaline, relative to a commercial Pt/C (E1/2, 0.851 VRHE). Meanwhile, this collective effect endows the shortened Fe−N bonds and the remarkable durability with negligible activity loss after 50,000 potential cycles. The ML was used to understand the intricate geometric and electronic interactions in collective effect and reveal the intrinsic descriptors to account for the enhanced ORR performance. The universality of collective effect was demonstrated effective for the Co, Ni, Cu, Cr, and Mn‐based multicomponent ensembles. These results confirm the importance of collective effect to simultaneously improve catalytic activity and durability. [ABSTRACT FROM AUTHOR]

Metal halide perovskite nanoplatelets (NPls) have recently joined a rich family of 2D semiconductor nanomaterials. Quantum and dielectric confinement in these nanostructures endow them with useful optical properties, which include, but are not limited to, high linear and nonlinear absorption coefficients, narrow and tunable emission bands, and high photoluminescence quantum yield. These characteristics render perovskite NPls promising for applications in lighting, photodetection, nonlinear optics, and photocatalysis. Doping is a universal approach for tuning optical and electronic properties of semiconductor materials, and the B‐site doping of perovskite NPls allows the further improvement and adjustment on demand of the above‐mentioned optical properties and may result in the appearance of fundamentally new behavior through embedding optically active dopants. In this mini‐review, the basic knowledge about perovskite NPls is shortly summarized in terms of their colloidal synthesis, and then the B‐site doping of perovskite NPls is considered in terms of the existing approaches (in situ and post‐synthetic doping) and its effect on the optical characteristics (doping with self‐emitting ions such as Mn2+ and rare‐earth elements; consequences for the nonlinear optical response). [ABSTRACT FROM AUTHOR]

Seeking new cathode chemistry with high onset potential and compatibility with electrolytes has become a challenge for aqueous Zn ion batteries. Anion intercalation in graphite (4.5 V vs Li+/Li) possesses the potentiality but usually shows a competitive relationship with oxygen evolution reaction (OER) in aqueous solutions. Herein, a decoupled design is proposed to optimize a full utilization of perchlorate ion intercalation in graphite cathode by pH adjustment. Benefiting from the decoupled design, high Coulombic efficiency is obtained by decelerating the kinetic of OER in acidic media. The decoupled Zn‐graphite battery exhibits a wide potential window of 2.01 V, as well as an attractive energy density of 231 Wh kg−1. In addition, a Zn‐graphite battery with SO42−${\mathrm{SO}}_4^{2 - }$ insertion is assembled, which demonstrates the capability of the proposed decoupled strategy to integrate novel electrode chemistries for high‐performance aqueous Zn‐based energy storage systems. [ABSTRACT FROM AUTHOR]

Addressing the limitations arising from the consistent catalytic behavior observed for various intermediates during the electrochemical carbon dioxide reduction reaction (CO2RR) poses a significant challenge in the optimization of catalytic activity. In this study, we aimed to address this challenge by constructing an asymmetric coordination Fe single atom catalyst (SCA) with a dynamically evolved structure. Our catalyst, consisting of a Fe atom coordinated with one S atom and three N atoms (Fe−S1N3), exhibited exceptional selectivity (CO Faradaic efficiency of 99.02 %) and demonstrated a high intrinsic activity (TOF of 7804.34 h−1), and remarkable stability. Using operando XAFS spectra and Density Functional Theory (DFT) calculations, we elucidated the self‐relaxation of geometric distortion and dynamic evolution of bond lengths within the catalyst. These structure changes enabled independent regulation of the *COOH and *CO intermediate adsorption energies, effectively breaking the linear scale relationship and enhancing the intrinsic activity of CO2RR. This study provides valuable insights into the dynamic evolution of SACs and paves the way for targeted catalyst designs aimed to disrupt the linear scaling relationships. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting holds great promise as a sustainable and cost‐effectiveness alternative for the production of hydrogen. Nevertheless, the practical implementation of this strategy is hindered by suboptimal visible light utilization and sluggish charge carrier dynamics, leading to low yield. MXene is a promising cocatalyst due to its high conductivity, abundance of active sites, tunable terminal functional groups, and great specific surface area. Homo‐interface has perfect lattice matching and uniform composition, which are more conducive to photogenerated carriers' separation and migration. In this study, a novel ternary heterogeneous photocatalyst, a‐TiO2/H‐TiO2/Ti3C2 MXene (MXTi), is presented using an electrostatic self‐assembly method. Compared to commercial P25, pristine anatase, and rutile TiO2, as‐prepared MXTi exhibit exceptional photocatalytic hydrogen evolution performance, achieving a rate of 0.387 mmol h−1. The significant improvement is attributable to the synergistic effect of homo‐interface engineering and Ti3C2 MXene, which leads to widened light absorption and efficient carrier transportation. The findings highlight the potential of interface engineering and MXene cocatalyst loading as a proactive approach to enhance the performance of photocatalytic water splitting, paving the way for more sustainable and efficient hydrogen production. [ABSTRACT FROM AUTHOR]

MXene quantum dots (MQDs) offer wide applications owing to the abundant surface chemistry, tunable energy‐level structure, and unique properties. However, the application of MQDs in electrochemical energy conversion, including hydrogen evolution reaction (HER), remains to be realized, as it remains a challenge to precisely control the types of surface groups and tune the structure of energy levels in MQDs, owing to the high surface energy–induced strong agglomeration in post‐processing. Consequently, the determination of the exact catalytically active sites and processes involved in such an electrocatalysis is challenging because of the complexity of the synthetic process and reaction conditions. Herein, we demonstrated the spontaneous evolution of the surface groups of the Ti2CTx MQDs (x: the content of O atom), i.e., replacement of the ‐Cl functional groups by O‐terminated ones during the cathode reaction. This process resulted in a low Gibbs free energy (0.26 eV) in HER. Our steady Ti2COx/Cu2O/Cu foam systems exhibited a low overpotential of 175 mV at 10 mA cm−2 in 1 M aq. KOH, and excellent operational stability over 165 h at a constant current density of −10 mA cm−2. [ABSTRACT FROM AUTHOR]

Perovskite‐based light‐emitting diodes (PeLEDs) with a mixed halide composition can be used to obtain the "pure red" emission, i.e., in the 620–650 nm range, required for high‐definition displays. However, fast halide ion migration induces phase separation in these materials under electric fields, resulting in poor spectral stability and low efficiency. Herein, a method for producing mixed halide CsPbI3‐xBrx quantum dots (QDs) is reported in which ion migration is suppressed. The mixed halide composition is first achieved by anion exchange between CsPbI3 QDs and hydrobromic acid (HBr), during that the bromine ions efficiently passivate the iodine vacancies of the QDs. The original oleic acid ligands are then exchanged for 1‐dodecanethiol (1‐DT), which suppresses halide ion migration via the strong binding of the sulfhydryl group with the QD surface. PeLEDs based on these QDs exhibit a pure‐red electroluminescence (EL) peak at 637 nm, a maximum external quantum efficiency (EQE) of 21.8% with an average value of 20.4%, a peak luminance of 2653 cd m−2, and low EQE decease with increasing luminance. The EL spectrum of these devices is stable even at 6.7 V and they have an EQE half‐life of 70 min at an initial luminance of 150 cd m−2. [ABSTRACT FROM AUTHOR]

Colloidal perovskite nanocrystals (NCs) have risen rapidly in luminescence efficiency and color purity. However, their high performance requires careful and complex pre‐treatment of precursors and precise regulation of the reaction atmosphere; otherwise, their emission will be weak and broad. To overcome these limitations, we develop a facile ligand exchange method using a new type of bidentate ligand, which is obtained by reacting cheap sulfur with tributylphosphine (S‐TBP). During ligand exchange, the double bond between P and S atoms breaks and a single bond is formed between them, after which S‐TBP switches into a bidentate ligand and binds to a perovskite NC at two points. With short‐chain S‐TBP ligands that have high spatial position resistance, both NC spacing and surface ligand density can be reduced, thereby improving carrier injection and transport. On the NC surface after ligand exchange, halogen vacancies were substantially filled, leading to a PbSP (Pb, S, and P elements) component‐dominated shell that greatly decreases trap density and enhances material stability. The resulting perovskite NCs are stable and bright with a photoluminescence quantum yield of ≈96 %, and an external quantum efficiency of 22 %. Note that our ligand‐exchange strategy remains effective even when scaling up, which should accelerate commercialization. [ABSTRACT FROM AUTHOR]

Lithium metal has been recognized as the most promising anode material due to its high capacity and low electrode potential. However, the high reactivity, infinite volume variation, and uncontrolled dendrites growth of Li during long‐term cycling severely limit its practical applications. To address these issues, herein, a novel 3D Al/Mg/Li alloy (denoted as AM‐Li) anode is designed and constructed by a facile smelting‐rolling strategy, which improves the surface stability, electrochemical cycling stability, and rate capability in lithium metal batteries. Specifically, the optimized AM‐Li|AM‐Li symmetric cell exhibits low polarization voltage (< 20 mV) and perfect cycling stability at 1 mA cm−2‐1 mAh cm−2 for more than 1600 h. Moreover, the AM‐Li|NCM811 full cell exhibits superior rate capability up to 5 C and excellent cyclability for 100 cycles at 0.5 C with a high capacity retention of 90.8%. The realization of lithium‐poor or lithium‐free anode materials will be a major development trend of anode materials in the future. Therefore, the research shows that the construction of 3D alloy framework is beneficial to improve the cycling stability of Li anodes by suppressing the volume expansion effect and Li dendrite growth, which will promote the further development of lithium‐poor metal anodes. [ABSTRACT FROM AUTHOR]

Retaining the ultrathin structure of two‐dimensional materials is very important for stabilizing their catalytic performances. However, aggregation and restacking are unavoidable, to some extent, due to the van der Waals interlayer interaction of two‐dimensional materials. Here, we address this challenge by preparing an origami accordion structure of ultrathin two‐dimensional graphitized carbon nitride (oa‐C3N4) with rich vacancies. This novel structured oa‐C3N4 shows exceptional photocatalytic activity for the CO2 reduction reaction, which is 8.1 times that of the pristine C3N4. The unique structure not only prevents restacking but also increases light harvesting and the density of vacancy defects, which leads to modification of the electronic structure, regulation of the CO2 adsorption energy, and a decrease in the energy barrier of the carbon dioxide to carboxylic acid intermediate reaction. This study provides a new avenue for the development of stable high‐performance two‐dimensional catalytic materials. [ABSTRACT FROM AUTHOR]

The interaction between electrode materials and charge carriers is one of the central issues dominating underlying energy storage mechanisms. To address the notoriously significant volume changes accompanying intercalation or formation of alloy/compounds, we aim to introduce and utilize a weak, reversible Fe–N interaction during the (de)intercalation of ammonium ions (NH4+) within iron(III) hexacyanoferrate (FeHCF), inspired by manipulating the electrostatic adsorption between N and Fe in the early stages of ammonia synthesis (Bosch‐Harber Process, Chemical Engineering) and steel nitriding processes (Metal Industry). Such strategy of switching well‐balanced Fe–N interaction is confirmed in between the nitrogen of ammonium ions and high‐spin Fe in FeHCF, as observed by using X‐ray absorption spectroscopy. The resulting material provided an extremely stable energy storage (58 mAh g−1 after 10 000 cycles at current density of 1 A g−1) as well as high‐rate performance (23.6 mAh g−1 at current density of 10 A g−1). [ABSTRACT FROM AUTHOR]

As a challenging problem in computer vision, salient object segmentation has attracted increasing attention in recent years. Though a lot of works based on encoder–decoder have been made, these methods can only recognize and segment one class of objects, but cannot segment the other classes of objects in the same image. To address this issue, this paper proposes a novel decoder based on Bayesian rules to perform task‐driven object segmentation, in which a control signal is added to the decoder to determine which class of objects need to be segmented. What's more, a Bayesian rule is established in the decoder, in which the control signal is set as the prior, and the latent features learned in encoder is transferred to the corresponding layer of decoder as observation, thus the posterior probability of each object with respect to the specific‐class can be calculated, and the objects belonging to this class can be segmented. This proposed method is evaluated for task‐driven salient object segmentation on several benchmark datasets, including MS COCO, DUT‐OMRON, ECSSD etc. Experimental results show that the approach tends to segment accurate, detailed, and complete objects, and improves the performance compared with the previous state‐of‐the‐art. [ABSTRACT FROM AUTHOR]

The working mechanism of a dual‐ion battery (DIB) differs from that of a lithium‐ion battery (LIB) in that the anions in the electrolyte of the former can be intercalated as well. Researchers have been paying close attention to this device because of its high voltage, low price, and environmental friendliness. However, DIBs are still in their early research stages, and numerous issues need to be addressed and investigated further. Initially, this Review explains how DIBs work in principle and discusses the progress of electrode materials for cathode and anode. Furthermore, since the electrolytes used as the active material, as well as anion, solvent, and additives, have a significant impact on the DIB's capacity and voltage, the current status is also presented in terms of electrolytes, followed by an outlook on confronting the challenges. A comprehensive summary from electrode to electrolyte will guide the development of next‐generation DIBs. [ABSTRACT FROM AUTHOR]

Efficient electrocatalytic reactions require a coordinated active center that may provide a properly reaction intermediates adsorption in water splitting. Herein, a Ni active center coordination reconstruction method achieved by multidimensional modulation of phase transition, iodine coordination, and vacancy defects is designed and implemented. This coordination reconstruction results in the successful synthesis of Ni5P4−xIx/Ni2P nanocorals that show outstanding bifunctional catalytic activity due to deep optimization of the adsorption energy. The overpotentials of hydrogen evolution reaction and oxygen evolution reaction at 10 mA cm−2 are 46 and 163 mV, respectively. Only 1.46 V is required to drive alkaline overall water splitting. Novel coordination environment is investigated by electron paramagnetic resonance spectroscopy and extended X‐ray absorption fine structure spectroscopy. A 4D integrated material design strategy of "thermodynamic stability‐electronic properties‐charge transfer‐adsorption energy" for water‐splitting catalysts is proposed. This coordination reconstruction concept and material design method provide new perspectives for the research of novel catalysts. [ABSTRACT FROM AUTHOR]

Energy density can be substantially raised and even maximized if the bulk of an electrode material is fully utilized. Transition metal oxides based on conversion reaction mechanism are the imperative choice due to either constructing nanostructure or intercalation pseudocapacitance with their intrinsic limitations. However, the fully bulk utilization of transition metal oxides is hindered by the poor understanding of atomic‐level conversion reaction mechanism, particularly it is largely missing at clarifying how the phase transformation (conversion reaction) determines the electrochemical performance such as power density and cyclic stability. Herein, α‐Fe2O3 is a case provided to claim how the diffusional and diffusionless transformation determine the electrochemical behaviors, as of its conversion reaction mechanism with fully bulk utilization in alkaline electrolyte. Specifically, the discharge product α‐FeOOH diffusional from Fe(OH)2 is structurally identified as the atomic‐level arch criminal for its cyclic stability deterioration, whereas the counterpart δ‐FeOOH is theoretically diffusionless‐like, unlocking the full potential of the pseudocapacitance with fully bulk utilization. Thus, such pseudocapacitance, in proof‐of‐concept and termed as conversion pseudocapacitance, is achieved via diffusionless‐like transformation. This work not only provides an atomic‐level perspective to reassess the potential electrochemical performance of the transition metal oxides electrode materials based on conversion reaction mechanism but also debuts a new paradigm for pseudocapacitance. [ABSTRACT FROM AUTHOR]

Accelerating slow water dissociation kinetics is key to boosting the hydrogen evolution reaction (HER) in alkaline media. We report the synthesis of atomically dispersed MoOx species anchored on Rh metallene using a one‐pot solvothermal method. The resulting structures expose the oxide‐metal interfaces to the maximum extent. This leads to a MoOx‐Rh catalyst with ultrahigh alkaline HER activity. We obtained a mass activity of 2.32 A mgRh−1 at an overpotential of 50 mV, which is 11.8 times higher than that of commercial Pt/C and surpasses the previously reported Rh‐based electrocatalysts. First‐principles calculations demonstrate that the interface between MoOx and Rh is the active center for alkaline HER. The MoOx sites preferentially adsorb and dissociate water molecules, and adjacent Rh sites adsorb the generated atomic hydrogen for efficient H2 evolution. Our findings illustrate the potential of atomic interface engineering strategies in electrocatalysis. [ABSTRACT FROM AUTHOR]

A selective shift in energy storage mechanisms is demonstrated by Wei Zhang, Weitao Zheng et al. in their Communication (e202405592). By meticulously engineering the oxygen vacancies within the α‐MoO3 structure, the selective insertion of H3O+ ions (blue droplets) in aqueous aluminum‐ion batteries is enabled...By Chengxiang Huang; Zhou Jiang; Fuxi Liu; Wenwen Li; Qing Liang; Zhenzhen Zhao; Xin Ge; Kexin Song; Lirong Zheng; Xinyan Zhou; Sifan Qiao; Wei Zhang and Weitao ZhengReported by Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

A selective shift in energy storage mechanisms is demonstrated by Wei Zhang, Weitao Zheng et al. in their Communication (e202405592). By meticulously engineering the oxygen vacancies within the α‐MoO3 structure, the selective insertion of H3O+ ions (blue droplets) in aqueous aluminum‐ion batteries is enabled...By Chengxiang Huang; Zhou Jiang; Fuxi Liu; Wenwen Li; Qing Liang; Zhenzhen Zhao; Xin Ge; Kexin Song; Lirong Zheng; Xinyan Zhou; Sifan Qiao; Wei Zhang and Weitao ZhengReported by Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Perovskite quantum dot (QD) charging is prone to occur during light‐emitting diode (LED) operation due to the electron accumulation inside the QD emitters, which is caused by the unbalanced charge injection and carrier transportation. Here in order to address this issue, an electron attractor of phenethylammonium (PEA+) is introduced to the surface of perovskite QDs. The PEA+ conjugated ligands can reversibly store and release electrons driven by the electron local density of states redistribution, which enhances the delocalization of electrons in QDs, and thus suppresses QD charging at high carrier concentrations, as evidenced by the excitation energy dependent photoluminescence. Besides, PEA+ down‐shifts the Fermi level of perovskite QDs, consequently increases the hole concentration, leading to greatly improved hole conduction. Halogen‐rich synthesis environment also reduces the number of halogen vacancies, consequently narrows the distribution of electronic states at the band edges, leading to slightly improved electron conduction. Taking advantage of the enhanced electron delocalization and improved charge transportation, the CsPbI3 QDs LEDs show the maximum external quantum efficiency (EQE) of 15.6% with a low efficiency roll‐off, and the maximum luminance of 1634 cd m−2. [ABSTRACT FROM AUTHOR]

Constructing earth‐abundant water splitting electrocatalysts performing platinum‐like activity is promising for the hydrogen economy but still a challenging task. Herein, the ultrafine CoMnP nanocrystals confined in amorphous carbon nanosheets are designed and implemented by a topological transformation strategy from layer double hydroxide/carbon interconnected structures in one single nanosheet. The unique interconnected structure favors the exposure of active sites and enables stronger electronic coupling effect between the two phases. Experimental results and density functional theory simulations reveal that the surrounding amorphous carbon and Mn dopants synergistically enable better electron delocalization capacity of Co sites, potentially providing enhanced conductivity and optimal reaction energetics during hydrogen evolution. The as‐prepared catalyst exhibits hydrogen evolution reaction performances superior to that of Pt/C under alkaline media with an overpotential of 114 mV at 100 mA cm–2. This work highlights the rational fabrication of transition metal‐based electrocatalysts via spatially confined growth for efficient water electrolysis. [ABSTRACT FROM AUTHOR]

Robust superlubricity (RSL), defined by concurrent superlow friction and wear, holds great promise for reducing material and energy loss in vast industrial and technological operations. Despite recent advances, challenges remain in finding materials that exhibit RSL on macrolength and time scales and possess vigorous electrical conduction ability. Here, the discovery of RSL is reported on hydrated NbB2 films that exhibit vanishingly small coefficient of friction (0.001–0.006) and superlow wear rate (≈10−17 m3 N−1 m−1) on large length scales reaching millimeter range and prolonged time scales lasting through extensive loading durations. Moreover, the measured low resistivity (≈10−6 Ω m) of the synthesized NbB2 film indicates ample capability for electrical conduction, extending macroscale RSL to hitherto largely untapped metallic materials. Pertinent microscopic mechanisms are elucidated by deciphering the intricate load‐driven chemical reactions that generate and sustain the observed superlubricating state and assessing the strong stress responses under diverse strains that produce the superior durability. [ABSTRACT FROM AUTHOR]

Developing the technology for high yielding photocatalytic hydrogen evolution reactions is an important challenge. Development and optimization of photocatalytic junctions is a likely route for achieving this if heterojunctions with suitable band alignments can be achieved in sufficiently high‐density form. Here, a novel anatase‐TiO2/H‐rutile‐TiO2 heterophase homojunction system with near optimum energy band alignment is reported. The resulting as‐prepared catalyst exhibits an excellent photocatalytic hydrogen evolution rate of 29.63 mmol g–1 h–1 under UV–vis light irradiation and an outstanding apparent quantum efficiency of 45.6% at 365 nm. The significant improvement is ascribed to near perfect lattice matching in combination with the rapid separation and transfer of photogenerated carriers in anatase‐TiO2/H‐rutile‐TiO2 heterophase homojunctions. In situ X‐ray photoelectron spectroscopy, electron spin resonance spin‐trapping tests, femtosecond transient absorption spectroscopy, steady‐state surface photovoltage spectroscopy, and transient‐state surface photovoltage with additional ex situ characterizations and theoretical calculations show that the mechanism is enhanced transfer of photogenerated carriers in the anatase‐TiO2/H‐rutile‐TiO2 catalyst. This work provides a pathway for enhancing photocatalytic performance through optimization of heterojunctions. [ABSTRACT FROM AUTHOR]

The next‐generation renewable energy machineries necessitate the electrodes with appropriate electrochemical performance. Here, the anodic properties of silicane for Li‐ and Na‐ion batteries were scrutinized employing first‐principle calculations. The projected single‐layer hydrogen‐functionalized Si (Si2H2) structure was energetically, mechanically, dynamically, and thermally stable based on theoretical simulations, confirming its experimental feasibility. The electronic properties revealed the semiconducting nature of silicane on the basis of PBE and HSE06 schemes with an indirect bandgap. As anode material for Li‐ and Na‐ion batteries, hydrogenated silicene showed promising electrochemical performance because of the proper adsorption strength between Si2H2 and the adsorbed Li and Na. The average open circuit voltages for Li2xSi2H2 and Na2xSi2H2 were as low as 0.42 and 0. 64 V, while its specific capacity was as high as 921 and 1842 mAh g−1 for Li and Na, respectively. It also showed ultra‐fast diffusion channels for Li and Na ions. The diffusion barriers for Li and Na migrations were as low as 0.18 and 0.14 eV, respectively, which revealed rapid charge/discharge processes using hydrogenated silicene as anode. These important features facilitate silicane as favorable anode material for Li/Na‐ion batteries. [ABSTRACT FROM AUTHOR]

The structural details of carbon materials directly affect their properties as an electrode material, such as specific capacitance and coulomb efficiency. Therefore, the structural analysis of carbon materials has always been an important step in the mechanistic insight into their roles in electrochemical energy storage. Raman spectroscopy, as molecular spectroscopy technique, has been widely used in understanding the lattice vibration mechanics of carbon materials and providing information on the chemical structure at molecular level, as well as microstructure analysis of carbon materials. In addition, the development of correlative‐Raman technology enables clarifying more comprehensive and accurate structural information for carbon‐based materials. With this information, it is of great significance to guide the construction of advanced carbon‐based electrode materials for energy storage. [ABSTRACT FROM AUTHOR]

The devise and fabrication of highly efficient electrocatalysts have momentous practical significance for the development of future hydrogen energy systems. However, their potential uses in support construction are not well studied. In this work, a highly efficient electrocatalyst is developed for the hydrogen evolution reaction by anchoring single Pt atoms and clusters into functional amorphous pentlandite Fe5Ni4S8 (or FNS) to yield Pt–FNS composites. Amorphous FNS still provides great conductivity to the composites, thereby promoting rapid charge transfer. The presence of abundant defects in Pt–FNS composite catalysts induces pleasant atomic dispersion and anchoring of Pt species. In addition, the formation of single Pt atoms combined with clusters and low‐Pt‐loading improves the utilization of Pt and reduces the cost. The turnover frequency analysis suggests Pt–FNS systems possess significant unit catalytic activity. The synergetic catalytic effect issued from high conductivity, abundant active sites and elevated intrinsic activity forms Pt–FNS systems with efficient pH‐universal catalytic activity. The systems exhibit low overpotentials of only 30, 65, and 98 mV at 10 mA cm−2 under acidic, alkaline, and neutral conditions, respectively. In sum, the proposed route looks promising for the fabrication of new electrocatalysts with improved properties. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are used to investigate the mechanical properties of finite‐width nanocrystalline gold nanoribbons with a thickness of one grain size under tensile strain. We find strong variations in the Young's modulus and flow stress especially for the sample with narrow width. With statistical analysis, Young's modulus has a trend of increase with the decrease of width. Flow stress does not follow this trend. Ductile fracture is observed at large strain in these nanocrystalline nanoribbons, but the fracture strain and mechanism are different from those of thick films as observed in existing experiments. For small widths below 80 nm, fracture is a necking effect, while for larger widths, shear bands and formation of nanovoids due to stress concentration are the main mechanism. Voids are mainly distributed in special GBs that are parallel to the direction of the maximum principal stress of the plastic deformation tensor. We find there is a width regime (about 80–130 nm) for the ultrathin nanoribbon gold, which have good ductility and large fracture strain. [ABSTRACT FROM AUTHOR]

Dual-ion battery, electrode materials, electrolyte, graphite, intercalation Keywords: dual-ion battery; electrode materials; electrolyte; graphite; intercalation EN dual-ion battery electrode materials electrolyte graphite intercalation 1 1 1 02/23/23 20230220 NES 230220 B The Front Cover b shows the working mechanism of dual-ion batteries (DIBs). [Extracted from the article]

In situ formation of gel polymer electrolytes (GPE) has been a promising candidate to address individual limitations of liquid/solid electrolytes and interfacial stability. However, the controllable conversion of liquid electrolyte (LE) precursor to GPE remains a great challenge with lower lithium‐ion transport, which is far from the demand for fast‐charging properties. Herein, a strategy of gradient polymerization of forming GPE is pioneered, stabilizing the electrolyte/electrode interface with an accelerated Li+ migration feature. As demonstrated by theoretical simulations and visualization experiment results, the formation mechanism of GPE via a partial inhibitory mechanism of Lithium nitrate (LiNO3) to control the solvent polymerization is comprehensively investigated, exhibiting the preferential interaction between nitrate anion (NO3−) and the Lewis acidic site in lithium bis(fluorosulfonyl)imide (LiFSI). Consequently, a stable amorphous GPE with high Li+ conductivity (5.10 mS cm−1) and an inorganic solid electrolyte interphase (SEI)‐dominate layer derived from spectroscopical measurements are achieved on the graphite electrode surface. The as‐prepared lithium iron phosphate (LFP)||graphite pouch cell stabilizes the capacity of 109.80 mAh g−1 (capacity retention: 80.02%) after 715 cycles at 5 C/1 C (charge/discharge), corresponding to the energy density of 277.64 Wh kg−1. This work provides a facile but practical approach to designing a highly stable GPE for fast‐charging lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

The electrooxidation of urea holds great potential for converting urea from wastewater into hydrogen, contributing to environmental protection and sustainable energy production. This necessitates the development of highly efficient and stable catalysts for the urea oxidation reaction (UOR). In this study, a NiCoCr‐LDH/NF (nickel‐cobalt‐chromium layered double hydroxide/nickel foam) electrode is successfully synthesized via a simple hydrothermal method, demonstrating excellent electrocatalytic performance with a low work potential of 1.38 V at a high current density of 100 mA cm−2. In situ, Raman spectra analysis revealed that the incorporation of chromium (Cr) facilitated the generation of active γ‐NiOOH species and catalyst reconstruction. Density functional theory (DFT) simulations confirmed that the lower formation energy of γ‐NiOOH is due to the weakened interaction of O─H bonds because of a narrow energy range of hybridization between O‐2pz orbitals and H‐1s orbitals. The introduction of Cr also improved the adsorption energy of urea molecules and its intermediates, thereby enhancing the overall activity of UOR. With its excellent electrocatalytic performance, unique electronic states, and coordination structures, the NiCoCr‐LDH/NF electrode showcases great potential for practical applications in the field of energy catalysis. [ABSTRACT FROM AUTHOR]

Robust superlubricity (RSL), defined by concurrent superlow friction and wear, holds great promise for reducing material and energy loss in vast industrial and technological operations. Despite recent advances, challenges remain in finding materials that exhibit RSL on macrolength and time scales and possess vigorous electrical conduction ability. Here, the discovery of RSL is reported on hydrated NbB2 films that exhibit vanishingly small coefficient of friction (0.001–0.006) and superlow wear rate (≈10−17 m3 N−1 m−1) on large length scales reaching millimeter range and prolonged time scales lasting through extensive loading durations. Moreover, the measured low resistivity (≈10−6 Ω m) of the synthesized NbB2 film indicates ample capability for electrical conduction, extending macroscale RSL to hitherto largely untapped metallic materials. Pertinent microscopic mechanisms are elucidated by deciphering the intricate load‐driven chemical reactions that generate and sustain the observed superlubricating state and assessing the strong stress responses under diverse strains that produce the superior durability. [ABSTRACT FROM AUTHOR]