Lithium Borohydride Nanorods: Self-Assembling Growth and Remarkable Hydrogen Cycling Properties.

Nanostructured metal hydrides with unique morphology and improved hydrogen storage properties have attracted intense interests. However, the study of the growth process of highly active borohydrides remains challenging. Herein, for the first time the synthesis of LiBH4 nanorods through a hydrogen-assisted one-pot solvothermal reaction is reported. Reaction of n-butyl lithium with triethylamine borane in n-hexane under 50 bar of H2 at 40-100 °C gives rise to the formation of the [100]-oriented LiBH4 nanorods with 500-800 nm in diameter, whose growth is driven by orientated attachment and ligand adsorption. The unique morphology enables the LiBH4 nanorods to release hydrogen from ≈184 °C, 94 °C lower than the commercial sample (≈278 °C). Hydrogen release amounts to 13 wt% within 40 min at 450 °C with a stable cyclability, remarkably superior to the commercial LiBH4 (≈9.1 wt%). More importantly, up to 180 °C reduction in the onset temperature of hydrogenation is successfully attained by the nanorod sample with respect to the commercial counterpart. The LiBH4 nanorods show no foaming during dehydrogenation, which improves the hydrogen cycling performance. The new approach will shed light on the preparation of nanostructured metal borohydrides as advanced functional materials.

Cu-N Synergism Regulation to Enhance Anionic Redox Reversibility and Activity of Li- and Mn-Rich Layered Oxides Cathode.

Anionic redox chemistry enables extraordinary capacity for Li- and Mn-rich layered oxides (LMROs) cathodes. Unfortunately, irreversible surface oxygen evolution evokes the pernicious phase transition, structural deterioration, and severe electrode-electrolyte interface side reaction with element dissolution, resulting in fast capacity and voltage fading of LMROs during cycling and hindering its commercialization. Herein, a redox couple strategy is proposed by utilizing copper phthalocyanine (CuPc) to address the irreversibility of anionic redox. The Cu-N synergistic effect of CuPc could not only inhibit surface oxygen evolution by reducing the peroxide ion O2 2- back to lattice oxygen O2-, but also enhance the reaction activity and reversibility of anionic redox in bulk to achieve a higher capacity and cycling stability. Moreover, the CuPc strategy suppresses the interface side reaction and induces the forming of a uniform and robust LiF-rich cathode electrolyte, interphase (CEI) to significantly eliminate transition metal dissolution. As a result, the CuPc-enhanced LMRO cathode shows superb cycling performance with a capacity retention of 95.0% after 500 long-term cycles. This study sheds light on the great effect of N-based redox couple to regulate anionic redox behavior and promote the development of high energy density and high stability LMROs cathode.

Unraveling the Unique Strong Metal-Support Interaction in Titanium Dioxide Supported Platinum Clusters for the Hydrogen Evolution Reaction.

Strong metal-support interaction (SMSI) is crucial to modulating the nature of metal species, yet the SMSI behaviors of sub-nanometer metal clusters remain unknown due to the difficulties in constructing SMSI at cluster scale. Herein, we achieve the successful construction of the SMSI between Pt clusters and amorphous TiO2 nanosheets by vacuum annealing, which requires a relatively low temperature that avoids the aggregation of small clusters. In situ scanning transmission electron microscopy observation is employed to explore the SMSI behaviors, and the results reveal the dynamic rearrangement of Pt atoms upon annealing for the first time. The originally disordered Pt atoms become ordered as the crystallizing of the amorphous TiO2 support, forming an epitaxial interface between Pt and TiO2. Such a SMSI state can remain stable in oxidation environment even at 400 °C. Further investigations prove that the electron transfer from TiO2 to Pt occupies the Pt 5d orbitals, which is responsible for the disappeared CO adsorption ability of Pt/TiO2 after forming SMSI. This work not only opens a new avenue for constructing SMSI at cluster scale but also provides in-depth understanding on the unique SMSI behavior, which would stimulate the development of supported metal clusters for catalysis applications.

Construction of Inorganic/Organic Hybrid Layer for Stable Na Metal Anode Operated under Wide Temperatures.

Sodium metal battery is supposed to be a propitious technology for high-energy storage application owing to the advantages of natural abundance and low cost. Unfortunately, the uncontrollable dendrite growth critically hampers its practical implementation. Herein, an inorganic/organic hybrid layer of NaF/CF/CC on the surface of Na foil (IOHL-Na) is designed and synthesized through the in situ reaction of polyvinylidene fluoride (PVDF) and metallic sodium. This protective layer possesses satisfactory Young's modulus, good kinetic property, and sodiophilicity, which can distinctly stabilize Na metal anode. As a result, the symmetric IOHL-Na cell achieves a lifespan of 770 h at 1 mAh cm-2 /1 mA cm-2 in carbonate electrolyte. The assembled full battery of IOHL-Na||Na3 V2 (PO4 )3 delivers a high discharge capacity of 85 mAh g-1 at 10 C after 600 cycles under ambient temperature. Furthermore, the IOHL-Na||Na3 V2 (PO4 )3 cell still can steadily operate at 10 C for 600 cycles at 55 °C. And when testing at an ultralow temperature of -40 °C, the full cell achieves 40 mAh g-1 at 0.5 C with a prolonged lifespan of 450 cycles. This work offers a new approach to protect the metal sodium anode without dendrite growth under wide temperatures.

A rare presentation of central pontine myelinolysis secondary to hyperglycaemia.

BACKGROUND: Central pontine myelinolysis (CPM) is a rare demyelinating disorder caused by the loss of myelin in the center of the basis pontis. CPM typically occurs with rapid correction of severe chronic hyponatremia and subsequent disturbances in serum osmolality. Although hyperglycaemia is recognized as a pathogenetic factor in serum osmolality fluctuations, CPM is rarely seen in the context of diabetes. CASE PRESENTATION: A 66-year-old Chinese male presented with a history of gait imbalance, mild slurred speech and dysphagia for two weeks. MRI showed the mass lesions in the brainstem, and laboratory examinations showed high blood glucose and HbA1c, as well as increased serum osmolality. The patient was diagnosed with CPM secondary to hyperosmolar hyperglyceamia and received insulin treatment as well as supportive therapy. After six weeks of followup, the patient had fully recovered to a normal state. CONCLUSION: CPM is a potentially fatal neurological condition and can occur in uncontrolled diabetes mellitus. Early diagnosis and timely treatment are crucial for improving the prognosis.

Rubus chingii Hu relieved the polycystic ovary syndrome with enhanced insulin sensitivity through inhibiting TXNIP/NLRP3 inflammasome signaling.

BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrine disorders in gynecology with severe metabolic abnormalities. Therefore, identifying effective treatments and drugs for PCOS is important. We aimed to investigate effect of the traditional Chinese medicine (TCM) Rubus chingii Hu (R. chingii) on ovarian function and insulin resistance (IR) of PCOS rat models, and to explore the underlying mechanisms. METHODS: A PCOS rat model was established by subcutaneous injection of dehydroepiandrosterone (DHEA) solution for 20 days. PCOS rats were randomly divided into a control group (CON), model group (MOD), metformin group (MET), TCM R. chingii group (RCG), and RCG + Ad-TXNIP groups. After 28 days of treatment, the samples were collected for subsequent experiments. RESULTS: R. chingii treatment alleviated hormone imbalance and IR while improving ovarian pathology in the PCOS model. R. chingi inhibited the activation of the thioredoxin-interacting protein (TXNIP)/NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome in the ovarian tissue of PCOS rats. Furthermore, TXNIP overexpression hindered the protective effect of R. chingii intervention in PCOS rats, as evidenced by the increase of homeostasis model assessment of insulin resistance (HOMA-IR), luteinizing hormone (LH), testosterone (T), C-reactive protein (CRP) levels, and atretic follicles. CONCLUSION: R. chingii intervention improved ovarian polycystic development by suppressing the TXNIP/NLRP3 inflammasome, which may be an effective treatment for PCOS.

Anion-exchange membrane water electrolyzers and fuel cells.

Anion-exchange membrane (AEM) water electrolyzers (AEMWEs) and fuel cells (AEMFCs) are technologies that, respectively, achieve transformation and utilization of renewable resources in the form of green hydrogen (H2) energy. The significantly reduced cost of their key components (membranes, electrocatalysts, bipolar plates, etc.), quick reaction kinetics, and fewer corrosion problems endow AEM water electrolyzers and fuel cells with overwhelming superiority over their conventional counterparts (e.g., proton-exchange membrane water electrolyzer/fuel cells and alkaline water electrolyzer/fuel cells). Limitations in our fundamental understanding of AEM devices, however, specifically in key components, working management, and operation monitoring, restrict the improvement of cell performance, and they further impede the deployment of AEM water electrolyzers and fuel cells. Therefore, a panoramic view to outline the fundamentals, technological progress, and future perspectives on AEMWEs and AEMFCs is presented. The objective of this review is to (1) present a timely overview of the market development status of green hydrogen technology that is closely associated with AEMWEs (hydrogen production) and AEMFCs (hydrogen utilization); (2) provide an in-depth and comprehensive analysis of AEMWEs and AEMFCs from the viewpoint of all key components (e.g., membranes, ionomers, catalysts, gas diffusion layers, bipolar plates, and membrane electrode assembly (MEA)); (3) summarize the state-of-the-art technologies for working management of AEMWEs and AEMFCs, including electrolyte engineering (electrolyte selection and feeding), water management, gas and heat management, etc.; (4) outline the advances in monitoring the operations of AEMWEs and AEMFCs, which include microscopic and spectroscopic techniques and beyond; and (5) present key aspects that need to be further studied from the perspective of science and engineering to accelerate the deployment of AEMWEs and AEMFCs.

Dual-Atom Support Boosts Nickel-Catalyzed Urea Electrooxidation.

Nickel-based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self-oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru-Co dual-atom support (Ru-Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru-Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm-2 and remarkable long-term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR.

Molecular Engineering on Solvation Structure of Carbonate Electrolyte toward Durable Sodium Metal Battery at -40 °C.

Carbonate electrolytes have excellent chemical stability and high salt solubility, which are ideally practical choice for achieving high-energy-density sodium (Na) metal battery at room temperature. However, their application at ultra-low temperature (-40 °C) is adversely affected by the instability of solid electrolyte interphase (SEI) formed by electrolyte decomposition and the difficulty of desolvation. Here, we designed a novel low-temperature carbonate electrolyte by molecular engineering on solvation structure. The calculations and experimental results demonstrate that ethylene sulfate (ES) reduces the sodium ion desolvation energy and promotes the forming of more inorganic substances on the Na surface, which promote ion migration and inhibit dendrite growth. At -40 °C, the Na||Na symmetric battery exhibits a stable cycle of 1500 hours, and the Na||Na3 V2 (PO4 )3 (NVP) battery achieves 88.2 % capacity retention after 200 cycles.

Ion Hopping: Design Principles for Strategies to Improve Ionic Conductivity for Inorganic Solid Electrolytes.

Solid electrolytes are considered as an ideal substitution of liquid electrolytes, avoiding the potential hazards of volatilization, flammability, and explosion for liquid electrolyte-based rechargeable batteries. However, there are significant performance gaps to be bridged between solid electrolytes and liquid electrolytes; one with a particular importance is the ionic conductivity which is highly dependent on the material types and structures. In this review, the general physical image of ion hopping in the crystalline structure is revisited, by highlighting two main kernels that impact ion migration: ion hopping pathways and skeletons interaction. The universal strategies to effectively improve ionic conductivity of inorganic solid electrolytes are then systematically summarized: constructing rapid diffusion pathways for mobile ions; and reducing resistance of the surrounding potential field. The scoped strategies offer an exclusive view on the working principle of ion movement regardless of the ion species, thus providing a comprehensive guidance for the future exploitation of solid electrolytes.

A Unique Nanoflake-Shape Bimetallic Ti-Nb Oxide of Superior Catalytic Effect for Hydrogen Storage of MgH2.

MgH2 is one of the most promising solid hydrogen storage materials due to its high capacity, excellent reversibility, and low cost. However, its operation temperature needs to be greatly reduced to realize its practical applications, especially in the highly desired fuel cell fields. This work synthesizes a 2D nanoflake-shape bimetallic Ti-Nb oxide of TiNb2 O7 , which has high surface area and shows superior catalytic effect for the hydrogen storage of MgH2 . Incorporated with the TiNb2 O7 nanoflakes as low as 3 wt%, MgH2 shows a low onset dehydrogenation temperature of 178 °C, which is lowered by 100 °C compared with the pristine one. A dehydrogenation capacity as high as 7.0 wt% H2 is achieved upon heating to 300 °C. The capacity retention is as high as 96% after 30 cycles. The mechanism of the improved hydrogen storage properties is analyzed by density functional theory (DFT) calculation and the microstructural evolution during dehydrogenation and hydrogenation. This work provides an MgH2 system with high available capacity and low operation temperature by a unique structural design of the catalyst. The high surface area feature of the TiNb2 O7 nanoflakes and the synthesis method hopefully can develop the application of TiNb2 O7 .

Multifunctional Surface Construction for Long-Term Cycling Stability of Li-Rich Mn-Based Layered Oxide Cathode for Li-Ion Batteries.

Li-rich Mn-based layered oxides (LMLOs) are promising cathode material candidate for the next-generation Li-ion batteries (LIBs) of high energy density. However, the fast capacity fading and voltage decay as well as low Coulombic efficiency caused by irreversible oxygen release and phase transition during the electrochemical process hinder their practical application. To solve these problems, in the present study, a multifunctional surface construction involving a coating layer, spinel-layered heterostructure, and rich-in oxygen vacancies is successfully conducted by a facile thermal reduction of the LMLO particles with potassium borohydride (KBH4 ) as the reducing agent. The multifunctional surface structure plays synergistic effects on suppressing the interface side reaction, reducing the dissolution of transition metal, increasing electron conductivity and lithium diffusion rate. As a result, electrochemical performances of the LMLO cathode are effectively enhanced. With optimization of the addition of KBH4 , the electrode delivers a reversible capacity of 280 mAh g-1 at 0.1 C, which maintains after 100 cycles. The capacity retention with respect to the initial capacity is as high as 98% at 1 C after 400 cycles. The present work provides insights into designing a highly effective functional surface structure of LMLO cathode materials for high-performance LIBs.

Cobalt Single Atoms Enabling Efficient Methanol Oxidation Reaction on Platinum Anchored on Nitrogen-Doped Carbon.

Developing efficient platinum (Pt)-based electrocatalysts with high tolerance to CO poisoning for the methanol oxidation reaction is critical for the development of direct methanol fuel cells. In this work, cobalt single atoms are introduced to enhance the electrocatalytic performance of N-doped carbon supported Pt (N-C/Pt) for the methanol oxidation reaction. The cobalt single atoms are believed to play a critical role in accelerating the prompt oxidation of CO to CO2 and minimizing the CO blocking of the adjacent Pt active sites. Benefitting from the synergistic effects among the Co single atoms, the Pt nanoparticles, and the N-doped carbon support, the Co-modified N-C/Pt (Co-N-C/Pt) electrocatalyst simultaneously delivers impressive electrocatalytic activity and durability with lower onset potential and superb CO poisoning resistance as compared to the N-C/Pt and the commercial Pt/C electrocatalysts.

Structure Engineering of Vanadium Tetrasulfides for High-Capacity and High-Rate Sodium Storage.

Structure engineering of electrode materials can significantly improve the life cycle and rate capability of the sodium-ion battery (SIB), yet remains a challenging task due to the lack of an effective synthetic strategy. Herein, the microstructure of VS4 hollow spheres is successfully engineered through a facile hydrothermal method. The hollow VS4 microspheres possess rich porosity and are covered with 2D ultrathin nanosheets on the surface. The finite element simulation (FES) reveals that such heterostructures can effectively relieve the stress induced by the sodiation and thereby enhance the structural integrity. The SIB with the hollow VS4 microspheres as anode displays impressively high specific capacity, excellent stability upon ultra-long cycling, and extraordinary rate capacity, e.g., a reversible capacity of ≈378 mA h g-1 at ultra-high 10 A g-1 , while retaining 73.2% capacity after 1000 cycles. The Na storage mechanism is also elucidated through in situ/ex situ characterizations. Moreover, the hollow VS4 microspheres demonstrate reliable rate performance at a low temperature of -40 °C (e.g., the capacity is ≈163 mA h g-1 at 2 A g-1 ). This work provides novel insights toward high-performance SIBs.

Electrocatalytic Water Splitting: From Harsh and Mild Conditions to Natural Seawater.

Electrocatalytic water splitting is regarded as the most effective pathway to generate green energy-hydrogen-which is considered as one of the most promising clean energy solutions to the world's energy crisis and climate change mitigation. Although electrocatalytic water splitting has been proposed for decades, large-scale industrial hydrogen production is hindered by high electricity cost, capital investment, and electrolysis media. Harsh conditions (strong acid/alkaline) are widely used in electrocatalytic mechanism studies, and excellent catalytic activities and efficiencies have been achieved. However, the practical application of electrocatalytic water splitting in harsh conditions encounters several obstacles, such as corrosion issues, catalyst stability, and membrane technical difficulties. Thus, the research on water splitting in mild conditions (neutral/near neutral), even in natural seawater, has aroused increasing attention. However, the mechanism in mild conditions or natural seawater is not clear. Herein, different conditions in electrocatalytic water splitting are reviewed and the effects and proposed mechanisms in the three conditions are summarized. Then, a comparison of the reaction process and the effects of the ions in different electrolytes are presented. Finally, the challenges and opportunities associated with direct electrocatalytic natural seawater splitting and the perspective are presented to promote the progress of hydrogen production by water splitting.

Latticed-Confined Conversion Chemistry of Battery Electrode.

The electrochemical conversion reaction, usually featured by multiple redox processes and high specific capacity, holds great promise in developing high-energy rechargeable battery technologies. However, the complete structural change accompanied by spontaneous atomic migration and volume variation during the charge/discharge cycle leads to electrode disintegration and performance degradation, therefore severely restricting the application of conventional conversion-type electrodes. Herein, latticed-confined conversion chemistry is proposed, where the "intercalation-like" redox behavior is realized on the electrode with a "conversion-like" high capacity. By delicately formulating the high-entropy compounds, the pristine crystal structure can be preserved by the inert lattice framework, thus enabling an ultra-high initial Coulombic efficiency of 92.5% and a long cycling lifespan over a thousand cycles after the quasistatic charge-discharge cycle. This lattice-confined conversion chemistry unfolds a ubiquitous insight into the localized redox reaction and sheds light on developing high-performance electrodes toward next-generation high-energy rechargeable batteries.

Smart Solar-Metal-Air Batteries Based on BiOCl Photocorrosion for Monolithic Solar Energy Conversion and Storage.

Herein, a BiOCl hydrogel film electrode featuring excellent photocorrosion and regeneration properties acts as the anode to construct a novel type of smart solar-metal-air batteries (SMABs), which combines the characteristics of solar cells (direct photovoltaic conversion) and metal-air batteries (electric energy storage and release interacting with atmosphere). The cyclic photocorrosion processes between BiOCl (Bi3+ ) and Bi can simply be achieved by solar light illumination and standing in the dark. Upon illumination, the device takes open-circuit configuration to charge itself from the sunlight. Notably, in this system, the converted solar energy can be stored in the SMABs without the need of external assistance. In the discharging process in the dark, Bi0 spontaneously turns back to Bi3+ producing electrons to induce the oxygen reduction reaction. With an illumination of 15 min, the battery with an electrode area of 1 cm2 can be continuously discharged for ≈3000 s. Taking elemental Bi as the calculation object, the theoretical capacity of the SMABs is 384.75 mAh g-1 , showing its potential application in energy storage. This novel type of SMABs is developed based on the unique photocorrosive and self-oxidation reaction of BiOCl to achieve photochemical energy generation and storage.

Plasmatic circRNAs Panel to Predict the Risk of Macrosomia in Women with Gestational Diabetes Mellitus.

OBJECTIVES: Fetal macrosomia and its associated complications are the most frequent and serious morbidities for infants associated with gestational diabetes mellitus (GDM). In this study, we aimed to determine the expression of circulating circRNAs in humans, which may be promising biomarkers for the diagnosis of GDM or predicting the macrosomia in GDM patients. DESIGN: A multi-stage validation and risk score formula analysis was applied for validation. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 26 circRNAs previously reported highly expressed in placenta tissues or umbilical cord blood of GDM patients during the pregnancy were enrolled. We recruited a total of 200 patients with GDM with or without macrosomia, 200 healthy pregnant woman, and 200 healthy volunteers. RESULTS: We discovered that four circRNAs including circRNA_1030, circRNA_23658, circRNA_0009049, and circRNA_32231 were upregulated in plasmatic samples of patients with GDM with or without macrosomia in training set and validation set compared with the healthy pregnant woman and healthy volunteers. Further receiver operating characteristic (ROC) curve analysis in risk score formula indicated a high diagnostic ability and area under ROC curve value (AUC) of 0.950 and 0.815 in training set and validation set for predicting GDM from controls group, for predicting macrosomia from GDM, the AUC was 0.975 and 0.820, respectively. The four circRNAs were further investigated with stable expression in human plasma samples. LIMITATIONS: The study was limited by larger scale of sample validation and the detailed mechanism investigation. CONCLUSION: The circRNA_1030, circRNA_23658, circRNA_0009049, and circRNA_32231 might be the potential biomarkers for predicting the GDM and macrosomia during the perinatal period.

Oxidative stress activates Ryr2-Ca2+ and apoptosis to promote PM2.5-induced heart injury of hyperlipidemia mice.

The increased cases of hyperlipemia in China and the crucial role of PM2.5 in inducing and promoting cardiovascular diseases have attracting more and more researchers' attention. However, the effects and mechanisms of PM2.5 on cardiovascular system of hyperlipidemia people are still unclear. In this study, hyperlipidemia mice model was established by high-fat diet. Then we exposed these mice to PM2.5 or saline to explore the underling mechanism of cardiac injury in hyperlipidemia mice. The hyperlipemia mice are more susceptible to heart damage caused by PM2.5 exposure. The participation of oxidative stress, cell apoptosis and Ca2+ related mechanism could be observed in this model. After NAC (N-acetyl-L-cysteine) treatment, the oxidative stress level induced by PM2.5 exposure significantly decreased in hyperlipemia mice. NAC effectively alleviated cardiac injury, improved the imbalance of calcium and attenuated apoptosis induced by PM2.5 exposure in hyperlipemia mice. The strong oxidative stress in hyperlipemia mice could lead to calcium homeostasis imbalance and activation of apoptosis-related pathways. This mechanism of PM2.5-induced myocardial injury was also verified in vitro. In our present study, we demonstrated the contribution of the PM2.5-ROS-Ryr2-Ca2+ axis in PM2.5-induced heart injury of hyperlipidemia mice, offering a potential therapeutical target for related pathology.

Atomic-Level Modulation of the Interface Chemistry of Platinum-Nickel Oxide toward Enhanced Hydrogen Electrocatalysis Kinetics.

Precise manipulation of the interactions between different components represents the frontier of heterostructured electrocatalysts and is crucial to understanding the structure-function relationship. Current studies, however, are quite limited. Here, we report targeted modulation of the atomic-level interface chemistry of Pt/NiO heterostructure via an annealing treatment, which results in substantially enhanced hydrogen electrocatalysis kinetics in alkaline media. Specifically, the optimized Pt/NiO heterostructure delivers by far the highest specific exchange current density of 8.1 mA cmPt-2 for hydrogen oxidation reaction. X-ray spectroscopy results suggest Pt-Ni interfacial bonds are formed after annealing, inducing more significant electron transfer from NiO to Pt. Also, the regulated interface chemistry, as proven by theoretical calculations, optimizes the binding behaviors of hydrogen and hydroxyl species. These findings emphasize the importance of interface engineering at the atomic level and inspire further explorations of heterostructured electrocatalysts.