Confined growth of Ultrathin, nanometer-sized FeOOH/CoP heterojunction nanosheet arrays as efficient self-supported electrode for oxygen evolution reaction.

Self-supported electrodes, featuring abundant active species and rapid mass transfer, are promising for practical applications in water electrolysis. However, constructing efficient self-supported electrodes with a strong affinity between the catalytic components and the substrate is of great challenge. In this study, by combining the ideas of in-situ construction and space-confined growth, we designed a novel self-supported FeOOH/cobalt phosphide (CoP) heterojunctions grown on a carefully modified commercial Ni foam (NF) with three-dimensional (3D) hierarchically porous Ni skeleton (FeOOH/CoP/3D NF). The specific porous structure of 3D NF directs the confined growth of FeOOH/CoP catalyst into ultra-thin and small-sized nanosheet arrays with abundant edge active sites. The active FeOOH/CoP component is stably anchored on the rough pore wall of 3D NF support, leading to superior stability and improved conductivity. These structural advantages contributed to a highly facilitated oxygen evolution reaction (OER) activity and enhanced durability of the FeOOH/CoP/3D NF electrode. Herein, the FeOOH/CoP/3D NF electrode afforded a low overpotential of 234 mV at 10 mA cm-2 (41 mV smaller than FeOOH/CoP grown on unmodified Ni foam) and high stability for over 90 h, which is among the top reported OER catalysts. Our study provides an effective idea and technique for the construction of active and robust self-supported electrodes for water electrolysis.

Amelioration of metabolic disorders in H9C2 cardiomyocytes induced by PM2.5 treated with vitamin C.

OBJECTIVE: Particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5) is a public health risk. We investigate PM2.5 on metabolites in cardiomyocytes and the influence of vitamin C on PM2.5 toxicity. MATERIALS AND METHODS: For 24 hours, H9C2 were exposed to various concentrations of PM2.5 (0, 100, 200, 400, 800 µg/ml), after which the levels of reactive oxygen species (ROS) and cell viability were measured using the cell counting kit-8 (CCK-8) and 2',7'-dichlorofluoresceindiacetate (DCFH2-DA), respectively. H9C2 were treated with PM2.5 (200 µg/ml) in the presence or absence of vitamin C (40 µmol/L). mRNA levels of interleukin 6(IL-6), caspase-3, fatty acid-binding protein 3 (FABP3), and hemeoxygenase-1 (HO-1) were investigated by quantitative reverse-transcription polymerase chain reaction. Non-targeted metabolomics by LC-MS/MS was applied to evaluate the metabolic profile in the cell. RESULTS: Results revealed a concentration-dependent reduction in cell viability, death, ROS, and increased expression of caspase-3, FABP3, and IL-6. In total, 15 metabolites exhibited significant differential expression (FC > 2, p < 0.05) between the control and PM2.5 group. In the PM2.5 group, lysophosphatidylcholines (LysoPC,3/3) were upregulated, whereas amino acids (5/5), amino acid analogues (3/3), and other acids and derivatives (4/4) were downregulated. PM2.5 toxicity was lessened by vitamin C. It reduced PM2.5-induced elevation of LysoPC (16:0), LysoPC (16:1), and LysoPC (18:1). DISCUSSION AND CONCLUSIONS: PM2.5 induces metabolic disorders in H9C2 cardiomyocytes that can be ameliorated by treatment with vitamin C.

Efficient Lithium/Sodium-Ion Storage by Core-Shell Carbon Nanospheres@TiO2 Decorate by Epitaxial WSe2 Nanosheets Derived from Bimetallic Polydopamine Composites.

Metal-polydopamine coordination chemistry attracts great attention owing to the synergistic effect of adjustable components and advantageous structures. However, few efforts have been devoted to exploring bimetal-polydopamine composites, especially for multistructural composites with high-capacity components and high stability. In this regard, the TiO2 @C-WSe2 core-shell nanospheres are designed and fabricated based on Ti-W-polydopamine composites after selenization, in which the TiO2 nanoparticles are encapsulated or embedded in the carbon nanospheres and the external WSe2 nanosheets are grown epitaxially on the carbon surfaces, featuring multiple channels for ion diffusion and abundant active edges for electrochemical reactions. The introduction of WSe2 not only greatly improves the capacity but also results in exponential growth of the active edge. As a result, the as-prepared TiO2 @C-WSe2 displayed long-term cycling performance in lithium-ion batteries. Furthermore, the anode is assembled into sodium-ion batteries, manifesting a stable capacity of 352 mA h g-1 at 1.0 A g-1 even after 2000 cycles, one of the best performances for polydopamine-based composites. Enhanced performance can be attributed to the synergies of high-capacity components and different dimensional materials. This work highlights that the rational design of functional structures provides a novel inspiration for electrodes with effective nanoarchitectures.

Unique Catalytic Mechanism for Ru-Loaded Ternary Intermetallic Electrides for Ammonia Synthesis.

Intermetallic electrides have recently shown their priority as catalyst components in ammonia synthesis and CO2 activation. However, their function mechanism has been elusive since its inception, which hinders the further development of such catalysts. In this work, ternary intermetallic electrides La-TM-Si (TM = Co, Fe, and Mn) were synthesized as hosts of ruthenium (Ru) particles for ammonia synthesis catalysis. Although they have the same crystal structure and possess low work functions commonly, the promotion effects on Ru particles rather differ from each other. The catalytic activity follows the sequence of Ru/LaCoSi > Ru/LaFeSi > Ru/LaMnSi. Furthermore, Ru/LaCoSi exhibits much better catalytic durability than the other two. A combination of experiments and first-principles calculations shows that apparent N2 activation energy on each catalyst is much lower than that over conventional Ru-based catalysts, which suggests that N2 dissociation can be conspicuously promoted by the concerted actions of the specific electronic structure and atomic configuration of intermetallic electride-supported catalysts. The NHx formations proceeded on La are energetically favored, which makes it possible to bypass the scaling relations based on only Ru as the active site. The rate-determining step of Ru/La-TM-Si was identified to be NH2 formation. The transition metal (TM) in La-TM-Si electrides has a significant influence on the metal-support interaction of Ru and La-TM-Si. These findings provide a guide for the development of new and effective catalyst hosts for ammonia synthesis and other hydrogenation reactions.

In-Situ growing tungsten Sulfide/Carbon nanosheets on sodium titanate nanorods to stabilize Surface-Structure for enhanced Sodium-ion storage.

Sodium-ions hybrid capacitors (SIHCs) have been recognized as one of the most potential energy storage devices, which can deliver high power and energy densities simultaneously. However, the sluggish kinetics of electrode materials severely restricts the performance of SIHCs. Herein, N, P-codoped carbon and WS2 nanosheets coating on sodium titanate nanorods (NTO@WS2/N, PC) were first designed by in-situ growing process and sulfuration treatment for boosting sodium-ion storage. Specifically, NTO@WS2/N, PC electrodes displayed a satisfactory specific capacity of 274.7 mAh g-1 at 3.0 A g-1 after 1200 cycles. Furthermore, as-assembled SIHCs delivered high-energy density of 112.1 Wh kg-1 and high-power density of 4334.4 W kg-1. Besides, long-term cycling test revealed that a remarkable capacity retention rate of 89.7% was obtained at 8.0 A g-1 after 2000 cycles. The excellent cycling stability and rate property could be ascribed to following aspects. On the one hand, N, P-codoped carbon could enhance the electrical conductivity and strengthen the structural integrality of the composites. On the other hand, ultrathin WS2 nanosheets and one-dimensional (1D) NTO nanorods structure were conducive to the rapid diffusion of Na+. This work provides a convenient technique to stabilize the structure of electrode materials, which can promote the practical application of SIHCs.

Boosting lithium-ion storage performance by ultrafine bimetal carbides nanoparticles coupled with Hollow-like carbon composites.

Metallic carbides demonstrated tremendous application potential in energy conversion field deriving from their distinctive electrochemical activity and chemical stability. Herein, a molybdenum-based hybrid self-template strategy was adopted to confine ultrafine molybdenum carbides and tungsten carbides nanoparticles in N, P-codoped carbon nanotubes (MoC/WC@N, P-CNTs) for enhanced lithium-ion storage. Specifically, hierarchical MoW-polydopamine nanotubes were prepared via a self-template strategy, which employed Mo3O10(C6H8N)2·2H2O nanowires as the template. Ultrafine MoC and WC nanoparticles embedded in ultrathin carbon nanosheets could be obtained rationally after carbonization treatment, which could not only prevent carbides nanoparticles from agglomeration and oxidation, but also endow the rapid electron transfer rate. Thus, MoC/WC@N, P-CNTs displayed outstanding lithium storage abilities with great rate property and long-term cycling durability. The stable specific capacity of 475.0 mAh g-1 could be preserved at high current intensity of 5.0 A g-1 after 1000 cycles, which was one of the best performances for metal carbides anodes. Furthermore, the successful fabrication of lithium-ion hybrid capacitors (LIHCs) delivered the maximum energy density of 117 Wh kg-1 and power density of 6571 W kg-1. Moreover, the superior capacity retention of 89.7 % after 2000 cycles also indicated the excellent cycling stability. The present work highlights a self-template strategy for designing nanostructures toward efficient energy storage and conversion fields.

Hierarchical core/shell titanium dioxide/molybdenum disulfide nanosheets coupled with carbon architecture for superior lithium/sodium ion storage.

The peculiar core/shell structure with abundant interfaces is favorable for Li+/Na+ storage, which can elevate the efficiency of energy storage and conversion. Herein, a unique core/shell structure composite with diverse interfaces was successfully designed and fabricated via a facile coordination reaction combined with thermal treatment. Specially, well-crystallized TiO2 nanoparticles were encapsulated and embedded in carbon nanospheres wrapped with MoS2 nanosheets, leading to abundant interfacial structure and boundaries. Benefitting from the synergistic effect between numerous interfaces and distinctive hierarchal core/shell structure, such a hybrid material possesses fascinating features including ultrafast ion diffusion, plentiful storage active sites and prominent electric conductivity. As a proof of concept, as-prepared samples demonstrated superior reversible lithium storage capacity and hybrid lithium-ion capacitor. What is more, when the material was acted as anode material for SIBs, the discharge capacity maintained at a high capacity of 267.2 mA h g-1 after 1000 cycles at 2.0 A g-1. This work highlights a convenient strategy to synthesize other hybrid materials for electrode materials of energy storage and conversion applications.

Interfacial Assembly of Nanowire Arrays toward Carbonaceous Mesoporous Nanorods and Superstructures.

Synthesis of anisotropic carbonaceous nano- and micro-materials with well-ordered mesoporous structures has attracted increasing attention for a broad scope of applications. Although hard-templating method has been widely employed, overcoming the viscous forces to prepare anisotropic mesoporous materials is particularly challenging via the universal soft-templating method, especially from sustainable biomass as a carbon resource. Herein, the synthesis of biomass-derived nanowire-arrays based mesoporous nanorods and teeth-like superstructures is reported, through a simple and straightforward polyelectrolyte assisted soft-templating hydrothermal carbonization (HTC) approach. A surface energy induced interfacial assembly mechanism with the synergetic interactions between micelles, nanowire, nanorods, and polyelectrolyte is proposed. The polyelectrolyte acts not only as a stabilizer to decrease the surface energy of cylindrical micelles, nanowires and nanorods, but also as a structure-directing agent to regulate the oriented attachment and anisotropic assembly of micelles, nanowires, and nanorods. After a calcination treatment, the carbon nanorod and teeth-like superstructure are successfully coupled with Ru to directly produce supported catalysts for the hydrogen evolution reaction, exhibiting much better performance than the isotropic nanospheres based catalyst. This HTC approach will open up new avenues for the synthesis of anisotropic materials with various morphologies and dimensions, expanding the palette of materials selection for many applications.

Facile Construction of Metal Phosphides (MP, M = Co, Ni, Fe, and Cu) Wrapped in Three-Dimensional N,P-Codoped Carbon Skeleton toward Highly Efficient Hydrogen Evolution Catalysis and Lithium-Ion Storage.

Transition metal phosphides (TMPs) have been demonstrated for prospective applications in electrocatalytic reaction and energy conversion owing to their specialties of catalytic activity and superhigh theoretical capacity. Herein, a facile and robust strategy for confining phosphides in a three-dimensional N,P-codoped carbon skeleton was achieved through a simple evaporation method. After calcination treatment, metal phosphide nanoparticles (MP, M = Co, Ni, Fe, and Cu) were successfully encapsulated in an interconnected N,P-codoped carbon network, which not only endowed high electrical conductivity and electrochemical stability but also provided more active sites and ion diffusion channels. As-prepared CoP@N,P-C exhibited satisfactory hydrogen evolution reaction activity, displaying lower overpotential of 140 and 197 mV at 10.0 mA cm-2 in 0.5 M H2SO4 and 1.0 M KOH, respectively. Moreover, CoP@N,P-C also delivered satisfactory lithium-ion storage properties. A higher specific capacity of 604.9 mAh g-1 was retained after 1000 cycles at 0.5 A g-1, one of the best reported performances of CoP-based anode materials. This work highlights a facile pathway to encapsulate metal phosphides in a conductive carbon skeleton, which is suitable for scaled-up production of bifunctional composites for efficient energy storage and conversion.

Epidemiological and genetic analysis concerning the non-enterovirus 71 and non-coxsackievirus A16 causative agents related to hand, foot and mouth disease in Anyang city, Henan Province, China, from 2011 to 2015.

Enterovirus 71 (EV-A71) and coxsackievirus A16 (CV-A16) are major pathogens of hand, foot, and mouth disease (HFMD) and have been associated with consecutive outbreaks of HFMD in China over the past years. Although several other human enteroviruses (HEVs) have also acted as causative agents of HFMD, published information on their roles in the prevalence of HFMD is limited. This study was conducted to reveal the characteristics of the pathogenic spectrum and molecular epidemiology of the non-EV-71 and -CV-A16 HEVs in Anyang City, which is located in north-central China and has a population of five million. From 2011 to 2015, 2270 samples were collected from HFMD patients (3.89 ± 1.06 years of age), and 1863 HEV-positive samples, including 524 samples with 23 non-EV-71 and non-CV-A16 serotypes, were identified. Based on the nucleotide sequence of the VP1 gene, 6 common non-EV-71 and non-CV-A16 HEVs, including coxsackievirus A2, A6, A10, A14, B2, and B5, were studied to determine their phylogenies and selective pressures. Phylogenetic analyses revealed a high level of genetic divergence and a pattern of lineage replacement over time in Mainland China. Selective pressure analyses showed that purifying selection was predominant in the evolution of the VP1 gene, whereas positive selection acted on individual codons. Overall, non-EV-71 and non-CV-A16 HEVs were important constituents of the pathogenic spectrum of HFMD in Anyang City during 2011-2015. Some of these HEVs with complex and active phylogenies represent a potential threat to public health, suggesting that long-term monitoring of these pathogens should be implemented to prevent HFMD outbreaks.

Molybdenum-Carbide-Modified Nitrogen-Doped Carbon Vesicle Encapsulating Nickel Nanoparticles: A Highly Efficient, Low-Cost Catalyst for Hydrogen Evolution Reaction.

Despite being promising substitutes for noble metal catalysts used in hydrogen evolution reaction (HER), the nonprecious metal catalysts (NPMCs) based on inexpensive and earth-abundant 3d transition metals (TMs) are still practically unfeasible due mainly to unsatisfactory activity and durability. Herein, a highly active and stable catalyst for HER has been developed on the basis of molybdenum-carbide-modified N-doped carbon vesicle encapsulating Ni nanoparticles (MoxC-Ni@NCV). This MoxC-Ni@NCV material was synthesized simply by the solid-state thermolysis of melamine-related composites of oxalate and molybdate with uniform Ni ions doping (Ni@MOM-com). Notably, the prepared MoxC-Ni@NCV was almost the most efficient NPMCs for HER in acidic electrolyte to date. Besides good long-term stability, MoxC-Ni@NCV exhibited a quiet low overpotential that was comparable to Pt/C. Thus, this work opens a new avenue toward the development of highly efficient, inexpensive HER catalysts.