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Sustaining the steady state for highly active non‐stoichiometric iridium (Ir)‐based oxide (IrOx) at low Ir loading remains challenging primarily due to the continuous oxidation and sequent dissolution of Ir active sites during the oxygen evolution reaction (OER). In this context, a new iridium–cerium (Ce) substitution solid solution oxide (SSO) has been developed, featuring uniformly dispersed Ir atoms within Ce dioxide (CeO2) matrix as electron buffer, which delivers remarkable acidic OER catalytic activity and enhanced stability. The electron‐buffering capacity of CeO2 facilitates the charge transfer toward Ir atoms, leading to abundant active low‐valence Ir sites and effectively prevent their oxidation and dissolution. As a result, Ir─Ce SSO demonstrates an overpotential of merely 238 mV@10 mA cm−2. Proton exchange membrane water electrolyzer employing Ir─Ce SSO at a low Ir loading of 396 µgIr cm−2 operates consistently for over 100 h@500 mA cm−2. Density functional theory (DFT) calculations corroborate that the electron‐buffering effect of CeO2 enriches the density of IrIII and substantially increases the dissolution energy barrier of Ir atoms. This study presents a viable approach to addressing the issues of instability and low efficiency in Ir‐based OER electrocatalysts for acidic water electrolysis. [ABSTRACT FROM AUTHOR]

Precisely modulating the Ru-O covalency in RuOx for enhanced stability in proton exchange membrane water electrolysis is highly desired. However, transition metals with d-valence electrons, which were doped into or alloyed with RuOx, are inherently susceptible to the influence of coordination environment, making it challenging to modulate the Ru-O covalency in a precise and continuous manner. Here, we first deduce that the introduction of lanthanide with gradually changing electronic configurations can continuously modulate the Ru-O covalency owing to the shielding effect of 5s/5p orbitals. Theoretical calculations confirm that the durability of Ln-RuOx following a volcanic trend as a function of Ru-O covalency. Among various Ln-RuOx, Er-RuOx is identified as the optimal catalyst and possesses a stability 35.5 times higher than that of RuO2. Particularly, the Er-RuOx-based device requires only 1.837 V to reach 3 A cm−2 and shows a long-term stability at 500 mA cm−2 for 100 h with a degradation rate of mere 37 μV h−1. Lack of stability in RuO2-based catalysts at industrial currents impedes their use in green hydrogen production. Here, the authors show that incorporating lanthanide elements into RuOx shields against external factors, enabling fine-tuned Ru-O covalency for durable oxygen evolution reaction electrocatalysis. [ABSTRACT FROM AUTHOR]

Covariance function estimation is a fundamental task in multivariate functional data analysis and arises in many applications. In this article, we consider estimating sparse covariance functions for high-dimensional functional data, where the number of random functions p is comparable to, or even larger than the sample size n. Aided by the Hilbert–Schmidt norm of functions, we introduce a new class of functional thresholding operators that combine functional versions of thresholding and shrinkage, and propose the adaptive functional thresholding estimator by incorporating the variance effects of individual entries of the sample covariance function into functional thresholding. To handle the practical scenario where curves are partially observed with errors, we also develop a nonparametric smoothing approach to obtain the smoothed adaptive functional thresholding estimator and its binned implementation to accelerate the computation. We investigate the theoretical properties of our proposals when p grows exponentially with n under both fully and partially observed functional scenarios. Finally, we demonstrate that the proposed adaptive functional thresholding estimators significantly outperform the competitors through extensive simulations and the functional connectivity analysis of two neuroimaging datasets. for this article are available online. [ABSTRACT FROM AUTHOR]

Sea level rise due to glacier melting caused by climate warming is a major global challenge, but the mechanism of the effect of salinity on soil carbon (C) mineralization in different land types is not clear. The pathways by which salinity indirectly affects soil carbon mineralization rates need to be investigated. Whether or not the response mode is consistent among different land-use types, as well as the intrinsic links and interactions between soil microbial resource limitation, environmental stress, microbial extracellular enzyme activity, and soil carbon mineralization, remain to be demonstrated. In this paper, three typical land-use types (wetland, forest, and agroforestry) were selected, and different salinity levels (0‰, 3‰, 6‰, and 32‰) were designed to conduct a 125-day laboratory incubation experiment to determine the soil CO2 release rate, soil physicochemical properties, and soil enzyme activities, and to correlate C mineralization with biotic and abiotic factors. A correlation analysis of soil physical and chemical properties, extracellular enzyme activities, and carbon mineralization rates was conducted to investigate their intrinsic linkages, and a multiple linear regression of C mineralization at different sites was performed to explore the variability of mineralization among different site types. Structural equation models were established in the pre- and post-incubation stages to study the pathways of soil C mineralization at different incubation times, and the mechanism of mineralization was further verified by enzyme stoichiometry. The results showed that, at the end of 125 days of incubation, the 32‰ salinity addition reduced the cumulative mineralization of forest and agroforestry types by 28.41% and 34.35%, respectively, compared to the 0‰ salinity addition. Soil C mineralization in the three different land-use types was highly correlated with the active C fractions of readily oxidizable C (ROC), dissolved organic C, and microbial biomass C (MBC) in the soil, with the standardized coefficients of multivariate linear regression reaching 0.67 for MBC in the wetland and −0.843 for ROC in the forest. Under long-term salinity additions, increased salinity would reduce the microbial respiratory quotient value by inhibiting β-glucosidase activity, thus indirectly affecting the rate of CO2 release. With added salinity, the mineralization of non-saline soil was more susceptible to the inhibitory effect of salinity, whereas the mineralization of salinized soil was more controlled by soil C pools. [ABSTRACT FROM AUTHOR]

Direct saline (seawater) electrolysis is a well‐recognized system to generate active chlorine species for the chloride‐mediated electrosynthesis, environmental remediation and sterilization over the past few decades. However, the large energy consumption originated from the high cell voltage of traditional direct saline electrolysis system, greatly restricts its practical application. Here, we report an acid‐saline hybrid electrolysis system for energy‐saving co‐electrosynthesis of active chlorine and H2. We demonstrate that this system just requires a low cell voltage of 1.59 V to attain 10 mA cm−2 with a large energy consumption decrease of 27.7 % compared to direct saline electrolysis system (2.20 V). We further demonstrate that such acid‐saline hybrid electrolysis system could be extended to realize energy‐saving and sustainable seawater electrolysis. The acidified seawater in this system can absolutely avoid the formation of Ca/Mg‐based sediments that always form in the seawater electrolysis system. We also prove that this system in the half‐flow mode can realize real‐time preparation of active chlorine used for sterilization and pea sprout production. [ABSTRACT FROM AUTHOR]

Direct saline (seawater) electrolysis is a well‐recognized system to generate active chlorine species for the chloride‐mediated electrosynthesis, environmental remediation and sterilization over the past few decades. However, the large energy consumption originated from the high cell voltage of traditional direct saline electrolysis system, greatly restricts its practical application. Here, we report an acid‐saline hybrid electrolysis system for energy‐saving co‐electrosynthesis of active chlorine and H2. We demonstrate that this system just requires a low cell voltage of 1.59 V to attain 10 mA cm−2 with a large energy consumption decrease of 27.7 % compared to direct saline electrolysis system (2.20 V). We further demonstrate that such acid‐saline hybrid electrolysis system could be extended to realize energy‐saving and sustainable seawater electrolysis. The acidified seawater in this system can absolutely avoid the formation of Ca/Mg‐based sediments that always form in the seawater electrolysis system. We also prove that this system in the half‐flow mode can realize real‐time preparation of active chlorine used for sterilization and pea sprout production. [ABSTRACT FROM AUTHOR]

The carbonate electrolyte chemistry is a primary determinant for the development of high‐voltage lithium metal batteries (LMBs). Unfortunately, their implementation is greatly plagued by sluggish electrode interfacial dynamics and insufficient electrolyte thermodynamic stability. Herein, lithium trifluoroacetate‐lithium nitrate (LiTFA−LiNO3) dual‐salt additive‐reinforced carbonate electrolyte (LTFAN) is proposed for stabilizing high‐voltage LMBs. We reveal that 1) the in situ generated inorganic‐rich electrode‐electrolyte interphase (EEI) enables rapid interfacial dynamics, 2) TFA− preferentially interacts with moisture over PF6− to strengthen the moisture tolerance of designed electrolyte, and 3) NO3− is found to be noticeably enriched at the cathode interface on charging, thus constructing Li+‐enriched, solvent‐coordinated, thermodynamically favorable electric double layer (EDL). The superior moisture tolerance of LTFAN and the thermodynamically stable EDL constructed at cathode interface play a decisive role in upgrading the compatibility of carbonate electrolyte with high‐voltage cathode. The LMBs with LTFAN realize 4.3 V‐NCM523/4.4 V‐NCM622 superior cycling reversibility and excellent rate capability, which is the leading level of documented records for carbonate electrode. [ABSTRACT FROM AUTHOR]

The carbonate electrolyte chemistry is a primary determinant for the development of high‐voltage lithium metal batteries (LMBs). Unfortunately, their implementation is greatly plagued by sluggish electrode interfacial dynamics and insufficient electrolyte thermodynamic stability. Herein, lithium trifluoroacetate‐lithium nitrate (LiTFA−LiNO3) dual‐salt additive‐reinforced carbonate electrolyte (LTFAN) is proposed for stabilizing high‐voltage LMBs. We reveal that 1) the in situ generated inorganic‐rich electrode‐electrolyte interphase (EEI) enables rapid interfacial dynamics, 2) TFA− preferentially interacts with moisture over PF6− to strengthen the moisture tolerance of designed electrolyte, and 3) NO3− is found to be noticeably enriched at the cathode interface on charging, thus constructing Li+‐enriched, solvent‐coordinated, thermodynamically favorable electric double layer (EDL). The superior moisture tolerance of LTFAN and the thermodynamically stable EDL constructed at cathode interface play a decisive role in upgrading the compatibility of carbonate electrolyte with high‐voltage cathode. The LMBs with LTFAN realize 4.3 V‐NCM523/4.4 V‐NCM622 superior cycling reversibility and excellent rate capability, which is the leading level of documented records for carbonate electrode. [ABSTRACT FROM AUTHOR]

The precise structural integration of single-atom and high-entropy-alloy features for energy electrocatalysis is highly appealing for energy conversion, yet remains a grand challenge. Herein, we report a class of single-atom Mo-tailored PdPtNiCuZn high-entropy-alloy nanosheets with dilute Pt-Pt ensembles and intrinsic tensile strain (Mo1-PdPtNiCuZn) as efficient electrocatalysts for enhancing the methanol oxidation reaction catalysis. The as-made Mo1-PdPtNiCuZn delivers an extraordinary mass activity of 24.55 A mgPt−1 and 11.62 A mgPd+Pt−1, along with impressive long-term durability. The planted oxophilic Mo single atoms as promoters modify the electronic structure of isolated Pt sites in the high-entropy-alloy host, suppressing the formation of CO adsorbates and steering the reaction towards the formate pathway. Meanwhile, Mo promoters and tensile strain synergistically optimize the adsorption behaviour of intermediates to achieve a more energetically favourable pathway and minimize the methanol oxidation reaction barrier. This work advances the design of atomically precise catalytic sites by creating a new paradigm of single atom-tailored high-entropy alloys, opening an encouraging pathway to the design of CO-tolerance electrocatalysts. Atomically precise modification of high-entropy alloys is highly appealing for electrocatalysis. Here, the authors design single-atom Mo-tailored high-entropy alloy nanosheets with dilute Pt-Pt ensembles and intrinsic tensile strain for promoting methanol electro-oxidation towards formate. [ABSTRACT FROM AUTHOR]

Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal–organic framework UiO‐67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme‐like nanocofactors that synergistically drive the ET process for enhanced peroxidase‐like catalysis. Among them, the linker‐coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29‐fold enhancement compared with the single effort of isolated metal site‐based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high‐performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale. [ABSTRACT FROM AUTHOR]

Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal–organic framework UiO‐67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme‐like nanocofactors that synergistically drive the ET process for enhanced peroxidase‐like catalysis. Among them, the linker‐coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29‐fold enhancement compared with the single effort of isolated metal site‐based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high‐performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale. [ABSTRACT FROM AUTHOR]

This document is a correction to an article titled "3D Vertically Aligned and Interconnected Porous Carbon Nanosheets as Sulfur Immobilizers for High Performance Lithium-Sulfur Batteries" published in Advanced Energy Materials. The correction addresses errors in several figures and text sections of the original article. The corrected figures and text provide accurate information about the reduction process, discharge capacities, long-term stability, and high-rate capability of the battery. The authors apologize for any inconvenience caused. [Extracted from the article]

Aqueous zinc‐ion batteries (AZIBs) are gaining popularity for their cost‐effectiveness, safety, and utilization of abundant resources. MXenes, which possess outstanding conductivity, controllable surface chemistry, and structural adaptability, are widely recognized as a highly versatile platform for AZIBs. MXenes offer a unique set of functions for AZIBs, yet their significance has not been systematically recognized and summarized. This review article provides an up‐to‐date overview of MXenes‐based electrode materials for AZIBs, with a focus on the unique functions of MXenes in these materials. The discussion starts with MXenes and their derivatives on the cathode side, where they serve as a 2D conductive substrate, 3D framework, flexible support, and coating layer. MXenes can act as both the active material and a precursor to the active material in the cathode. On the anode side, the functions of MXenes include active material host, zinc metal surface protection, electrolyte additive, and separator modification. The review also highlights technical challenges and key hurdles that MXenes currently face in AZIBs. [ABSTRACT FROM AUTHOR]

The repair of bone defects in diabetes remains a major challenge in the field of biomedicine because of the disturbance of bone immune homeostasis and the susceptibility of exposed wounds to bacterial infection. Clinically, immunoregulation by removing excessive reactive oxygen species (ROS) effectively promotes diabetic bone defect repair. However, aggressive ROS clearance can disrupt ROS homeostasis, making ROS‐mediated polarization of M2 macrophages in the process of tissue healing of diabetes be difficult. Herein, an ultrathin defective tungsten oxide (WOx) nanoribbon with high oxygen vacancies to simultaneously achieve moderate scavenging of ROS and high broad‐spectrum photothermal antibacterial activity to promote diabetic bone defect repair is reported. It is demonstrated that the moderate ROS clearance ability of WOx nanoribbons can remodel metabolic patterns for achieving 86.3% M2 macrophage induction in a high glucose microenvironment. This high induction efficiency combined with excellent photothermal antibacterial ability of WOx nanoribbons markedly alleviated the inflammatory reaction and efficiently facilitated the repair of bone defects infected with methicillin‐resistant Staphylococcus aureus (S. aureus) in C57BLKS/J (BKS)‐diabetic (BKS‐db) mice. [ABSTRACT FROM AUTHOR]

With the increase in haze pollution in Chinese cities, answering the question of whether using a high-speed rail (HSR) as a green and efficient transportation system can alleviate haze pollution in China has become a research hotspot. This study empirically tests the impact of HSR network construction on haze pollution and its spatial spillover effects. (1) The construction of a HSR would have a mitigation effect on haze pollution in node cities and surrounding cities, and the more developed the HSR is, the more significant that this effect would be. (2) Haze pollution persists for a long time, the haze pollution from the previous year may have a positive promoting effect on the haze pollution in the following year. (3) The use of a HSR reduces haze pollution by replacing traditional road transportation and promoting industrial structure upgrading and technological innovation. (4) The inhibitory effect of HSR use on haze pollution varies due to regional differences and variation in city size. [ABSTRACT FROM AUTHOR]

Platinum metal (PtM, M=Ni, Fe, Co) alloys catalysts show high oxygen reduction reaction (ORR) activity due to their well‐known strain and ligand effects. However, these PtM alloys usually suffer from a deficient ORR durability in acidic environment as the alloyed metal is prone to be dissolved due to its high electronegativity. Herein, we report a new class of PtMn alloy nanodendrite catalyst with low‐electronegativity Mn‐contraction for boosting the oxygen reduction durability of fuel cells. The moderate strain in PtMn, induced by Mn contraction, yields optimal oxygen reduction activity at 0.53 A mg−1 at 0.9 V versus reversible hydrogen electrode (RHE). Most importantly, we show that relative to well‐known high‐electronegativity Ni‐based Pt alloy counterpart, the PtMn nanodendrite catalyst experiences less transition metals' dissolution in acidic solution and achieves an outstanding mass activity retention of 96 % after 10,000 degradation cycles. Density functional theory calculation reveals that PtMn alloys are thermodynamically more stable than PtNi alloys in terms of formation enthalpy and cohesive energy. The PtMn nanodendrite‐based membrane electrode assembly delivers an outstanding peak power density of 1.36 W cm−2 at a low Pt loading and high‐performance retention over 50 h operations at 0.6 V in H2‐O2 hydrogen fuel cells. [ABSTRACT FROM AUTHOR]

Platinum metal (PtM, M=Ni, Fe, Co) alloys catalysts show high oxygen reduction reaction (ORR) activity due to their well‐known strain and ligand effects. However, these PtM alloys usually suffer from a deficient ORR durability in acidic environment as the alloyed metal is prone to be dissolved due to its high electronegativity. Herein, we report a new class of PtMn alloy nanodendrite catalyst with low‐electronegativity Mn‐contraction for boosting the oxygen reduction durability of fuel cells. The moderate strain in PtMn, induced by Mn contraction, yields optimal oxygen reduction activity at 0.53 A mg−1 at 0.9 V versus reversible hydrogen electrode (RHE). Most importantly, we show that relative to well‐known high‐electronegativity Ni‐based Pt alloy counterpart, the PtMn nanodendrite catalyst experiences less transition metals' dissolution in acidic solution and achieves an outstanding mass activity retention of 96 % after 10,000 degradation cycles. Density functional theory calculation reveals that PtMn alloys are thermodynamically more stable than PtNi alloys in terms of formation enthalpy and cohesive energy. The PtMn nanodendrite‐based membrane electrode assembly delivers an outstanding peak power density of 1.36 W cm−2 at a low Pt loading and high‐performance retention over 50 h operations at 0.6 V in H2‐O2 hydrogen fuel cells. [ABSTRACT FROM AUTHOR]

Photocatalytic aerobic oxidation desulfurization (PAODS) is a promising and sustainable alternative to conventional, energy-intensive desulfurization techniques for petroleum products. However, its development is greatly plagued by the low capability in generating highly reactive oxygen species and sluggish kinetics of sulfide oxidation of reported photocatalysts. Here we report a class of MoOx nanocluster decorated on ultrathin Mo-doped TiO2 nanosheet (MoOx/MoTiO) catalyst for efficiently facilitating the photocatalytic aerobic oxidation of sulfides. We demonstrate that MoOx/MoTiO can not only promote the generation of highly reactive singlet oxygen (1O2) but also enhance the aerobic conversion of sulfides, which leads to a record dibenzothiophene oxidation activity of 3.90 mmol g−1 h−1. The multiple experimental characterizations and density functional theory calculations collectively reveal that the doped-Mo sites can interact with the photogenerated excitons, enabling directly energy transfer generation of 1O2 through a new exciton modulation mechanism, and the coordination unsaturated MoOx clusters play the role of co-catalyst to enhance the separation of charge carriers, and effectively catalyze the reaction between sulfides and 1O2 to form sulfones. [ABSTRACT FROM AUTHOR]

To realize the reduction in cutting force and guarantee pruning section quality in the pruning and stubble work of Caragana korshinskii (C.K.), a concentric curvilineal edge sliding cutter was proposed and the related cutting characteristics were studied. The impacts of branch diameter (D), cutting speed ( V c ), blade wedge angle ( β ), cutting clearance ( c ) and moisture content (W) on peak torque (T) and cutting energy (E) with this cutter were explored in single-factor tests. On the basis of the Box—Behnken principle, a multi-factor test was further conducted based on the single-factor tests with V c , β and c as influencing factors and with T and E as targets, and a regression model was established. Test results indicate that the peak torque (T) increases with the increase in D and β and reduces with the growth of V c and W; with the increase in c , it reduces first and then rises; the cutting energy (E) increases with the growth of D and β , declines with the increase in W and diminishes first and then rises with the increase in V c and c . The optimal parameter combination of the regression model was obtained with V c of 2.16 rad/s, β of 20 ° and c of 1.0 mm, which resulted in a T of 17.25 N·m and P of 7.03 J. The discrepancies between the observed and forecasted values for T and E are 0.87% and 5.004%. New cutting tool and data support for the development of subsequent C.K. branch stubble equipment can be obtained with this new sliding cutter. [ABSTRACT FROM AUTHOR]

Ligand effect, induced by charge transfer between catalytic surface and substrate in core/shell structure, was widely proved to benefit Pt-catalyzed oxygen reduction reaction by tuning the position of d-band center of Pt theoretically. However, ligand effect is always convoluted by strain effect in real core/shell nanostructure; therefore, it remains experimentally unknown whether and how much the ligand effect solely contributes electrocatalytic activity improvements. Herein, we report precise synthesis of a kind of Pd3Ru1/Pt core/shell nanoplates with exclusive ligand effect for oxygen reduction reaction. Layer-by-layer growth of Pt overlayers onto Pd3Ru1 nanoplates can guarantee no lattice mismatch between core and shell because the well-designed Pd3Ru1 has the same lattice parameters as Pt. Electron transfer, due to the exclusive ligand effect, from Pd3Ru1 to Pt leads to a downshift of d-band center of Pt. The optimal Pd3Ru1/Pt1-2L nanoplates achieve excellent activity and stability for oxygen reduction reaction in alkaline/acid electrolyte. Deconvoluting and quantitating ligand effect from the typical strain-ligand effects in a real catalytic structure remains challenging. Here, the authors report a core/shell catalyst model to quantitate how much ligand effect solely contributes to electrocatalytic performance through experimental design. [ABSTRACT FROM AUTHOR]

Neurotoxicity of organophosphate compounds (OPs) can catastrophically cause nervous system injury by inhibiting acetylcholinesterase (AChE) expression. Although artificial systems have been developed for indirect neuroprotection, they are limited to dissociating P-O bonds for eliminating OPs. However, these systems have failed to overcome the deactivation of AChE. Herein, we report our finding that Al3+ is engineered onto the nodes of metal–organic framework to synthesize MOF-808-Al with enhanced Lewis acidity. The resultant MOF-808-Al efficiently mimics the catalytic behavior of AChE and has a self-defense ability to break the activity inhibition by OPs. Mechanism investigations elucidate that Al3+ Lewis acid sites with a strong polarization effect unite the highly electronegative –OH groups to form the enzyme-like catalytic center, resulting in superior substrate activation and nucleophilic attack ability with a 2.7-fold activity improvement. The multifunctional MOF-808-Al, which has satisfactory biosafety, is efficient in reducing neurotoxic effects and preventing neuronal tissue damage. The neurotoxicity of organophosphate compounds damages nerve system by inhibiting acetylcholinesterase (AChE) expression, but it is difficult to overcome the deactivation of AChE. Here, the authors report the design of Lewis acid sites in metal-organic frameworks as AChE mimics for effective neuroprotection. [ABSTRACT FROM AUTHOR]

Large‐area continuous covalent organic frameworks (COFs) film is highly desirable for the large‐scale continuous selective photocatalytic coupling of benzylamine (BA); however, traditional synthetic methods for preparing COFs films still suffer from the issues of harsh reaction condition, film breakage, and high energy‐consumption. Herein, a room‐temperature strategy is reported for making large‐area continuous imine‐based COFs film through the "infiltration‐reaction‐assembly" mechanism, demonstrating that such strategy is quite universal for making four types of large‐area COFs films. The as‐made PyTTA‐TPA (PyTTA: 1，3，6，8‐tetrakis(4‐aminophenyl)pyrene, TPA: p‐benzaldehyde) COFs film exhibits excellent catalytic performance for selective photocatalytic coupling of benzylamine (BA) with a high conversion rate of 98.2% and high selectivity of 97% in 3 h, which is the best photocatalytic performance in all reported photocatalysts. In addition, the as‐made COFs film is quite general for achieving photocatalytic coupling of other amine derivatives with outstanding photocatalytic performance of ≈100% conversion rate. Overall, this work brings a significant development for the room‐temperature synthesis of large‐area continuous COFs film to photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Spreading the formic acid (HCOOH) fuel cells demands a better anode electrocatalyst for the oxidation of formic acid. The catalytic efficiency of platinum (Pt)– the only choice of practicability, is mainly limited by its intrinsic affinity to CO, thus desiring a proper release. Herein, theoretical calculations are first leveraged to find that the introduction of iridium (Ir) can facilitate HCOOH oxidation with robust CO tolerance through a dehydrogenation pathway. Then, this strategy experimentally by designing a new trimetallic catalyst of 2D porous PtIrBi nanoplates (p‐PtIrBi NPs) is implemented. The optimized p‐PtIrBi NPs/C exhibits a very high mass activity of 8.2 A mg−1pt and a high retention rate of 55.9% after the durability test, which is among the best formic acid oxidation catalysts reported to date, much higher than those of PtIrBi NPs/C, PtBi NPs/C, and Pt/C. The CO‐stripping and in situ Fourier transform infrared (FTIR) experiments collectively evidence that two types of due site, i.e., "Pt‐Bi" and "Ir‐Bi", endow the catalyst with suppressed CO‐poisoning property to achieve super‐high activity and stability for formic acid oxidation reaction. [ABSTRACT FROM AUTHOR]

Metamaterials are usually designed using biomimetic technology based on natural biological characteristics or topology optimization based on prior knowledge. Although satisfactory results can be achieved to a certain extent, there are still many performance limitations. For overcoming the above limitations, this paper proposes a rapid metamaterials design method based on the generation of random topological patterns. This method realizes the combined big data simulation and structure optimization of structure-electromagnetic properties, which makes up for the shortcomings of traditional design methods. The electromagnetic properties of the proposed metamaterials are verified by experiments. The reflection coefficient of the designed absorbing metamaterial unit is all lower than −15 dB over 12–16 GHz. Compared with the metal floor, the radar cross section (RCS) of the designed metamaterial is reduced by a minimum of 14.5 dB and a maximum of 27.6 dB over the operating band. The performance parameters of metamaterial obtained based on the random topology design method are consistent with the simulation design results, which further verifies the reliability of the algorithm in this paper. [ABSTRACT FROM AUTHOR]

Solar-driven photosynthesis is a sustainable process for the production of hydrogen peroxide, the efficiency of which is plagued by side reactions. Metal-free covalent organic frameworks (COFs) that can form suitable intermediates and inhibit side reactions show great promise to photo-synthesize H2O2. However, the insufficient formation and separation/transfer of photogenerated charges in such materials restricts the efficiency of H2O2 production. Herein, we provide a strategy for the design of donor-acceptor COFs to greatly boost H2O2 photosynthesis. We demonstrate that the optimal intramolecular polarity of COFs, achieved by using suitable amounts of phenyl groups as electron donors, can maximize the free charge generation, which leads to high H2O2 yield rates (605 μmol g−1 h−1) from water, oxygen and visible light without sacrificial agents. Combining in-situ characterization with computational calculations, we describe how the triazine N-sites with optimal N 2p states play a crucial role in H2O activation and selective oxidation into H2O2. We further experimentally demonstrate that H2O2 can be efficiently produced in tap, river or sea water with natural sunlight and air for water decontamination. Solar-driven photosynthesis is a green and sustainable process for hydrogen peroxide production. Here the authors report that optimizing the intramolecular polarity of COFs can greatly boost H2O2 photosynthesis from water, air, and sunlight. [ABSTRACT FROM AUTHOR]

Carrier migration path and driving forces are two crucial factors for charge separation of heterojunction with efficient photoelectric response from the thermodynamic and kinetic perspectives, respectively. Constructing the S-scheme heterojunction and achieving an efficient migration path for space charge separation have aroused great interest, while a thorough insight into tuning interfacial band bending for S-scheme heterojunction is absent. Herein, we report a class of Zn atom-doped CeO2/g-C3N4 heterostructure for achieving a new carrier migration path conversion from inferior type-II to advanced S-scheme. Zn-dependent volcano-type plot for Zn-CeO2 is established to tune the Fermi level of CeO2. The built-in electric field for carrier flow dynamics strengthens when coupling with g-C3N4, which significantly boosts the photoelectric response. Based on the intrinsic enzymelike activity of Zn-CeO2, we further demonstrate that the Zn-CeO2/g-C3N4 S-scheme heterojunction can be explored for constructing a sensitive nanozymatic photoelectrochemical biosensor for the detection of acetylcholinesterase. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Oxygen reduction reaction (ORR) is the pivotal portion in many electrochemical energy conversion and storage technologies. However, the complex mechanisms and sluggish kinetics of ORR have also become one of the key issues hindering the development and application of these technologies. Recently, single‐atom catalysts (SACs) with well‐defined atomic active centers and theoretical 100% atomic utilization have attracted broad interests in the area of electrocatalytic ORR. The electrocatalytic ORR performance of SACs is fundamentally determined by the intrinsic activity of the single‐atom active site and increasing the number of active sites involved in the ORR can further enhance the ORR activity of SACs. In this review, advances in atomically dispersed metal electrocatalysts for ORR in the last three years are summarized. Three main regulation strategies for achieving SACs with excellent intrinsic activity in the context of the ORR mechanism are involved including modulation of coordination environments, the construction of intrinsic defects, and the introduction of dual active sites. Moreover, discussions on improving the loading and utilization of active sites are given. Finally, the current challenges and opportunities for the development of SACs for ORR are presented. [ABSTRACT FROM AUTHOR]

We consider the two‐sample mean testing problem for infinite‐dimensional functional data and present a new testing procedure. The proposed hard‐thresholding test statistic is based on the normalized functional principal component scores and allows the number of components diverging with the sample size. The hard‐thresholding part is introduced for the power improvement. The asymptotic normality of the statistic is derived under both the null hypothesis and some local alternatives. We also design a power enhancement component based on L2‐norm to further alleviate the power loss under certain alternatives. We conduct extensive numerical simulations and analyze a real example to demonstrate the superiority of the proposed test to several competitors. [ABSTRACT FROM AUTHOR]

Transition‐metal atomic site catalysts (ASCs) are a new class of catalytic system for CO2 electroreduction, however, their practical application is greatly hindered by the challenge that it's still difficult for them to simultaneously achieve industrial‐level current density and high selectivity. Herein a new strategy is reported for hundreds of gram‐scale and low‐cost production of Ni‐ASCs on 3D porous nanocarbon with high‐loading NiN3 sites for greatly boosting the electroreduction of CO2 to CO with both industrial‐level current density and high selectivity. It is discovered that although Ni‐ASCs with high‐loading (Ni‐ASCs/4.3 wt.%) and low‐loading (Ni‐ASCs/0.8 wt.%) both show above 95% Faradic efficiency for CO (FECO) under a wide potential range in H‐cell, in flow cell, Ni‐ASCs/0.8 wt.% can only achieve FECO of 43.6% at a current density of 343.9 mA cm−2, significantly lower than those (95.1%, 533.3 mA cm−2) of Ni‐ASCs/4.3 wt.% under same potential, first revealing the important role of high‐loadings of single atom sites in promoting the high‐selectivity electrolysis at industrial‐level current density. Most importantly, it is demonstrated that Ni‐ASCs/4.3 wt.%‐based membrane electrode assembly (MEA) exhibits outstanding durability at industrial‐level current density of 360.0 mA cm−2, which is one of the best performances for the realistic electroreduction of CO2 to CO in the reported ASCs‐based MEA systems. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) show great potential as anodes for potassium‐ion batteries (PIBs) due to their high theoretical capacity and relatively low working potential. However, usually the conversion mechanism seriously hinders the long‐term cycle stability for PIBs due to the huge structural change. Herein, the synthesis of a class of ultrathin metallic 2H‐phase NbS2 nanosheets with large expanded interlayer spacing of 0.65 nm and high conductivity for boosting the potassium ion storage is reported. It is demonstrated that the as‐prepared NbS2 nanosheets show an unexpected intercalation mechanism for potassium ion storage, which is conceptually different from the well‐known intercalation‐conversion mechanism of typical TMDs. As a consequence, the ultrathin NbS2 nanosheets deliver superior rate capability (205.5 mAh g−1 at ultrahigh current density of 10 A g−1) and outstanding long‐term cycling performance (169.5 mAh g−1 at 5 A g−1 after 4000 cycles with a very low decay rate of 0.005% per cycle), representing the most stable TMD‐based anode materials for PIBs. Ex situ measurements and first‐principles calculations disclose and interpret that NbS2 nanosheets store potassium ions through only the intercalation mechanism without any conversion reaction taking place in the potassiation/depotassiation process, which highly improves the structural stability of electrode materials, hence promoting the long‐term cycle performance. [ABSTRACT FROM AUTHOR]

As emerging eutectic mixtures, deep eutectic electrolytes (DEEs) show unique properties for Li‐metal batteries (LMBs). However, the limited choice and inferior electrode compatibility hinder their further development in LMBs. Herein, we report a new 1,2‐dimethylimidazole (DMIm)‐based deep eutectic gel polymer electrolyte induced by Li−N interaction. We demonstrate that incorporating electron‐withdrawing polyvinylidene difluoride (PVDF) polymer into the DMIm‐based DEE changes the coordination environment of Li+ ions, leading to a high transference number of Li+ ions (0.65) and superior interface stability between the electrolyte and Li anode. The deep eutectic gel polymer electrolyte exhibits excellent non‐flammability, high ionic conductivity (1.67 mS cm−1 at 30 °C), and high oxidation voltage (up to 4.35 V vs. Li/Li+). The Li||LFP cell based on the newly developed deep eutectic gel polymer electrolyte can achieve superior long‐term cycling stability at a wide range of rates. [ABSTRACT FROM AUTHOR]

As emerging eutectic mixtures, deep eutectic electrolytes (DEEs) show unique properties for Li‐metal batteries (LMBs). However, the limited choice and inferior electrode compatibility hinder their further development in LMBs. Herein, we report a new 1,2‐dimethylimidazole (DMIm)‐based deep eutectic gel polymer electrolyte induced by Li−N interaction. We demonstrate that incorporating electron‐withdrawing polyvinylidene difluoride (PVDF) polymer into the DMIm‐based DEE changes the coordination environment of Li+ ions, leading to a high transference number of Li+ ions (0.65) and superior interface stability between the electrolyte and Li anode. The deep eutectic gel polymer electrolyte exhibits excellent non‐flammability, high ionic conductivity (1.67 mS cm−1 at 30 °C), and high oxidation voltage (up to 4.35 V vs. Li/Li+). The Li||LFP cell based on the newly developed deep eutectic gel polymer electrolyte can achieve superior long‐term cycling stability at a wide range of rates. [ABSTRACT FROM AUTHOR]