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The aim of this study was to examine whether administration of valproic acid (VPA), a histone deacetylase inhibitor, inhibits proinflammatory mediators and ameliorate visceral vasopermeability both in a rat model of major burn, and also in rat cultured endothelial cells stimulated with permeability evoking mediators. SD rats were subjected to a 50% TBSA full-thickness scald injury, and treated with either saline or VPA (300 mg/kg) intraperitoneally. Pulmonary vascular endothelial growth factor (VEGF), myeloperoxidase (MPO), pulmonary microvascular permeability, water content, and acetylation of histone H3K9 of lungs were evaluated. In addition, pulmonary microvascular endothelial cells (PMECs) from male SD rats were cultured. With then, MPO, VEGF, histone acetylation, and the permeability of PMECs were investigated. Lethal scald injury resulted in a significant increase in microvascular permeability and water content of lung, accompanied by a significant elevation of the content of VEGF and activity of MPO, and a decrease of histone acetylation. VPA treatment significantly alleviated the microvascular permeability and water content of lung, lowered the levels of VEGF and MPO, and promoted acetylation of histone H3K9 following scald injury. Moreover, VPA reduced permeability of monolayer PMECs subjected to scald serum challenge, reduced the level of MPO and VEGF in supernatants, and promoted acetylation of histone H3K9 in PMECs. These results indicated that VPA can protect pulmonary microvascular endothelial barrier, alleviate proinflammatory mediators-evoked vascular hyperpermeability and tissue edema and improve the survival rate of rats subjected to lethal scald injury.

Increasing CO2 concentration in the atmosphere is believed to have a profound impact on the global climate. To reverse the impact would necessitate not only curbing the reliance on fossil fuels but also developing effective strategies capture and utilize CO2 from the atmosphere. Among several available strategies, CO2 reduction via the electrochemical or photochemical approach is particularly attractive since the required energy input can be potentially supplied from renewable sources such as solar energy. In this Review, an overview on these two different but inherently connected approaches is provided and recent progress on the development, engineering, and understanding of CO2 reduction electrocatalysts and photocatalysts is summarized. First, the basic principles that govern electrocatalytic or photocatalytic CO2 reduction and their important performance metrics are discussed. Then, a detailed discussion on different CO2 reduction electrocatalysts and photocatalysts as well as their generally designing strategies is provided. At the end of this Review, perspectives on the opportunities and possible directions for future development of this field are presented.

Reversible electrochemical storage of alkali metal ions is the basis of many secondary batteries. Over years, various electrode materials are developed and optimized for a specific type of alkali metal ions (Li

A facile colloidal route to synthesize MoSe2 porous microspheres with diameters of 400–600 nm made up of MoSe2 monolayer flakes (∼0.7 nm in thickness) is reported. The solvents trioctylamine (TOA) and oleylamine (OAM) are found to play important roles in the formation of MoSe2 microspheres, whereby TOA determines the three-dimensional (3D) microspherical morphology and OAM directs the formation of MoSe2 monolayer flakes. The robust 3D MoSe2 microspheres exhibit remarkable activity and durability for the electrocatalytic hydrogen evolution reaction (HER) in acid, maintaining a small onset overpotential of ∼77 mV and keeping a small overpotential of 100 mV for a current density of 5 mA/cm2 after 1,000 cycles. In addition, similar 3D WSe2 microspheres can also be prepared by using this method. We expect this facile colloidal route could further be expanded to synthesize other porous structures which will find applications in fields such as in energy storage, catalysis, and sensing.

The rising global energy demand has stressed the need to develop and implement novel materials and methods for sustainably harvesting, conserving, and using energy [1]?[6]. The ability to control the interconversion of energy from one form to another with a high rate and efficiency at low cost is essential. Electrochemistry is a fundamental science to study the conversion between electrical and chemical energies. Its principle has been applied to a range of energy technologies, including batteries, fuel cells, and electrolytic or solar water splitting devices [1]?[6]. In contrast to fossil fuel combustion, electrochemical reactions are direct and clean processes with minimal environmental impact. They are not limited by Carnot efficiency and therefore can attain substantially higher efficiency than, for example, a conventional heat engine at low temperatures [7].

Zn vacancy (VZn) effects on the microstructure and ferromagnetism (FM) of Zn0.94Cr0.06O nanorod arrays have been investigated using a combination of experimental measurements and first-principles calculations. The well-aligned Zn0.94Cr0.06O nanorod arrays were synthesized by radio frequency magnetron sputtering deposition at different substrate temperatures. The Cr K-edge X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy results revealed that the Cr3+ ions were located at the substitutional Zn sites. Moreover, the O K-edge XANES analysis and resonance Raman scattering indicated the existence of numerous VZn. The stable FM observed at room temperature was an intrinsic property of Zn0.94Cr0.06O nanorod arrays. With increasing substrate temperature, improved crystallinity along with the increase in VZn was observed in Zn0.94Cr0.06O nanorod arrays, and an enhancement of magnetic moment in the samples came forth. First-principles calculations revealed that the enhanced magnetism mainly comes from the unsaturated 2p orbitals of the surrounding O atoms, which is caused by the presence of the Zn vacancy. This research represents a novel promising route for tuning the magnetic behavior of nano-dilute magnetic semiconductor systems via VZn changes.

Zinc-air is a century-old battery technology but has attracted revived interest recently. With larger storage capacity at a fraction of the cost compared to lithium-ion, zinc-air batteries clearly represent one of the most viable future options to powering electric vehicles. However, some technical problems associated with them have yet to be resolved. In this review, we present the fundamentals, challenges and latest exciting advances related to zinc-air research. Detailed discussion will be organized around the individual components of the system - from zinc electrodes, electrolytes, and separators to air electrodes and oxygen electrocatalysts in sequential order for both primary and electrically/mechanically rechargeable types. The detrimental effect of CO2 on battery performance is also emphasized, and possible solutions summarized. Finally, other metal-air batteries are briefly overviewed and compared in favor of zinc-air.

The development of nonprecious metal based electrocatalysts for hydrogen evolution reaction (HER) has received increasing attention over recent years. Previous studies have established Mo

Electrochemical CO2 reduction to fuels and commodity chemicals offers an attractive solution for energy and environmental sustainability. Formic acid (or formate) is suggested to be one of the most economically viable products. However, in order to realize its commercial viability, a drastic improvement of the electrocatalyst materials on both activity and selectivity is required. Here we report that structural defects have a profound positive impact on the electrocatalytic performance of Bi for selective CO2 reduction to formate. Bi2O3 double-walled nanotubes with fragmented outer surface are prepared as the template. They are cathodically converted to highly defective Bi nanotubes as evidenced by operando X-ray absorption spectroscopy measurements. This converted electrocatalyst enables CO2 reduction to formate with excellent activity, selectivity and stability. Importantly, its current density reaches ~288 mA cm-2 at -0.61 V versus reversible hydrogen electrode within a flow cell reactor under ambient conditions, which substantially exceeds the commercialization requirement. Using density functional theory calculations, the excellent activity and selectivity are rationalized as the outcome of abundant defective Bi sites that stabilize the *OCHO intermediate. Furthermore, this electrocatalyst is coupled with Si photocathodes and achieves high-performance photoelectrochemical CO2 reduction.

Many problems of Li-S batteries essentially root in their polysulfide intermediates. While conventional wisdom mainly focuses on trapping polysulfides at the cathode using various functional materials, few strategies are available at present to fully resolve or circumvent this long-standing issue. In this study, we propose the concept of sulfur-equivalent cathode materials, and demonstrate the great potential of amorphous MoS3 as such a material for room-temperature Li-S and Na-S batteries. When evaluated in Li-S batteries, MoS3 exhibits sulfur-like behavior with large reversible specific capacity when normalized to the sulfur weight (~1400 mAh/gS at 50 mA/gS), excellent cycle life (~850 mAh/gS after 1000 cycles at 1 A/gS), exceptional high rate capability (420 mAh/gS at 20 A/gS) and possibility to achieve high areal capacity (~2.8 mAh/cm2). Most remarkably, it is also fully cycleable in the carbonate electrolyte under a relatively high temperature of 55oC. MoS3 can also be used as the cathode material of even more challenging Na-S batteries to enable an unprecedented performance. In-situ XAS experiments evidence that MoS3 preserves its chain-like structure free of polysulfide intermediates during repetitive battery cycling.

Correction for ‘Weakening hydrogen adsorption on nickel via interstitial nitrogen doping promotes bifunctional hydrogen electrocatalysis in alkaline solution’ by Tingting Wang et al., Energy Environ. Sci., 2019, DOI: 10.1039/c9ee01743g.

Next-generation catalysts for water splitting are crucial towards a renewable hydrogen economy. MoS2 and WS2 represent earth-abundant, noble metal cathode alternatives with high catalytic activity at edge sites. One challenge in their development is to nanostructure these materials in order to achieve increased performance through the creation of additional edge sites. In this work, we demonstrate a simple route to form nanostructured-WS2 using sonochemical exfoliation to break interlayer and intralayer bonds in WS2 nanotubes. The resulting few-layer nanoflakes are ∼100 nm wide with a high density of edge sites. WS2 nanoflakes are utilized as cathodes for the hydrogen evolution reaction (HER) and exhibit superior performance to WS2 nanotubes and bulk particles, with a lower onset potential, shallower Tafel slope and increased current density. Future work may employ ultra-small nanoflakes, dopant atoms, or graphene hybrids to further improve electrocatalytic activity. Open image in new window

Highly active, durable, and cost-effective electrocatalysts for water oxidation to evolve oxygen gas hold a key to a range of renewable energy solutions, including water-splitting and rechargeable metal-air batteries. Here, we report the synthesis of ultrathin nickel-iron layered double hydroxide (NiFe-LDH) nanoplates on mildly oxidized multiwalled carbon nanotubes (CNTs). Incorporation of Fe into the nickel hydroxide induced the formation of NiFe-LDH. The crystalline NiFe-LDH phase in nanoplate form is found to be highly active for oxygen evolution reaction in alkaline solutions. For NiFe-LDH grown on a network of CNTs, the resulting NiFe-LDH/CNT complex exhibits higher electrocatalytic activity and stability for oxygen evolution than commercial precious metal Ir catalysts.

Electrochemical systems, such as fuel cell and water splitting devices, represent some of the most efficient and environmentally friendly technologies for energy conversion and storage. Electrocatalysts play key roles in the chemical processes but often limit the performance of the entire systems due to insufficient activity, lifetime, or high cost. It has been a long-standing challenge to develop efficient and durable electrocatalysts at low cost. In this Perspective, we present our recent efforts in developing strongly coupled inorganic/nanocarbon hybrid materials to improve the electrocatalytic activities and stability of inorganic metal oxides, hydroxides, sulfides, and metal-nitrogen complexes. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of inorganic nanomaterials on the functional groups of oxidized nanocarbon substrates including graphene and carbon nanotubes. This approach affords strong chemical attachment and electrical coupling between the electrocatalytic nanoparticles and nanocarbon, leading to nonprecious metal-based electrocatalysts with improved activity and durability for the oxygen reduction reaction for fuel cells and chlor-alkali catalysis, oxygen evolution reaction, and hydrogen evolution reaction. X-ray absorption near-edge structure and scanning transmission electron microscopy are employed to characterize the hybrids materials and reveal the coupling effects between inorganic nanomaterials and nanocarbon substrates. Z-contrast imaging and electron energy loss spectroscopy at single atom level are performed to investigate the nature of catalytic sites on ultrathin graphene sheets. Nanocarbon-based hybrid materials may present new opportunities for the development of electrocatalysts meeting the requirements of activity, durability, and cost for large-scale electrochemical applications.

Increasing attention has now been focused on the photoelectrochemical (PEC) hydrogen evolution as a promising route to transforming solar energy into chemical fuels. Silicon is one of the most studied PEC electrode materials, but its performance is still limited by its inherent PEC instability and electrochemical inertness toward water splitting. To achieve significant PEC activities, silicon-based photoelectrodes usually have to be coupled with proper cocatalysts, and thus, the formed semiconductor-cocatalyst interface presents a critical structural parameter in the rational design of efficient PEC devices. In this study, we directly grow nanostructured pyrite-phase nickel phosphide (NiP

The search for high-capacity, low-cost electrode materials for sodium-ion batteries is a significant challenge in energy research. Among the many potential candidates, layered compounds such as MoS2 have attracted increasing attention. However, such materials have not yet fulfilled their true potential. Here, we show that networks of liquid phase exfoliated MoS2 nanosheets, reinforced with 20 wt % single-wall carbon nanotubes (SWNTs), can be formed into sodium-ion battery electrodes with large gravimetric, volumetric, and areal capacity. The MoS2/SWNT composite films are highly porous, electrically conductive, and mechanically robust due to its percolating carbon nanotube network. When directly employed as the working electrode, they exhibit a specific capacity of400 mAh/g and volumetric capacity of ∼650 mAh/cm(3). Their mechanical stability allows them to be processed into free-standing films with tunable thickness up to ∼100 μm, corresponding to an areal loading of 15 mg/cm(2). Their high electrical conductivity allows the high volumetric capacity to be retained, even at high thickness, resulting in state-of-the-art areal capacities of4.0 mAh/cm(2). Such values are competitive with their lithium-ion counterparts.

Accumulating studies have demonstrated that long noncoding RNAs (lncRNAs) act a crucial role in the development of tumors. However, the role of lncRNAs in lung cancer remains largely unknown. In this study, we demonstrated that theexpression of RMRP was upregulated in lung adenocarcinoma tissues compared to the matched adjacent normal tissues. Moreover, of 35 lung adenocarcinoma samples, RMRP expression was upregulated in 25 cases (25/35; 71.4%) compared to the adjacent normal tissues. We also showed that RMRP expression was upregulated in lung adenocarcinoma cell lines (A549, SPC-A1, H1299 and H23) compared to the bronchial epithelial cell line (16HBE). Ectopic expression of RMRP promoted lung adenocarcinoma cell proliferation, colony formation and invasion. In addition, overexpression of RMRP inhibited the miR-206 expression in the H1299 cell and increased the KRAS, FMNL2 and SOX9 expression, which were the target genes of miR-206. Re-expression of miR-206 reversed the RMRP-induced the H1299 cell proliferation and migration. Our data proved that RMRP acted as an oncogene LncRNA to promote the expression of KRAS, FMNL2 and SOX9 by inhibiting miR-206 expression in lung cancer. These data suggested that RMRP might serve as a therapeutic target in lung adenocarcinoma.

Electrocatalyst for oxygen reduction reaction (ORR) is crucial for a variety of renewable energy applications and energy-intensive industries. The design and synthesis of highly active ORR catalysts with strong durability at low cost is extremely desirable but remains challenging. Here, we used a simple two-step method to synthesize cobalt oxide/carbon nanotube (CNT) strongly coupled hybrid as efficient ORR catalyst by directly growing nanocrystals on oxidized multiwalled CNTs. The mildly oxidized CNTs provided functional groups on the outer walls to nucleate and anchor nanocrystals, while retaining intact inner walls for highly conducting network. Cobalt oxide was in the form of CoO due to a gas-phase annealing step in NH(3). The resulting CoO/nitrogen-doped CNT (NCNT) hybrid showed high ORR current density that outperformed Co(3)O(4)/graphene hybrid and commercial Pt/C catalyst at medium overpotential, mainly through a 4e reduction pathway. The metal oxide/carbon nanotube hybrid was found to be advantageous over the graphene counterpart in terms of active sites and charge transport. Last, the CoO/NCNT hybrid showed high ORR activity and stability under a highly corrosive condition of 10 M NaOH at 80 °C, demonstrating the potential of strongly coupled inorganic/nanocarbon hybrid as a novel catalyst system in oxygen depolarized cathode for chlor-alkali electrolysis.

Manganese oxides are cost-effective and green materials with rich electrochemical properties. Continuous research efforts have been undertaken to obtain MnO x materials with improved activity and stability for catalyzing the oxygen reduction reaction (ORR). Here, we have developed a novel ORR catalyst by nucleation and growth of Mn3O4 nanoparticles on graphene oxide (GO) sheets interconnected by electrically conducting multi-walled carbon nanotubes (MWCNTs). X-ray near edge absorption structure (XANES) spectroscopy revealed the partially reduced nature of GO and strong chemical coupling between the nanoparticles and the GO sheets. Incorporation of MWCNTs was found to improve the activity and stability of the hybrid by imparting higher conductivity to the hybrid material. Furthermore, surface oxidation of the manganese oxide nanoparticles through a calcination step was found to increase the density of ORR active sites. The strongly coupled and electrically interconnected Mn3O4/nanocarbon (Mn3O4/Nano-C) hybrid is one of the most active and stable manganese oxide-based ORR catalysts and shows promise for electrochemical energy conversion applications.

We investigated the chlorine plasma reaction with graphene and graphene nanoribbons and compared it with the hydrogen and fluorine plasma reactions. Unlike the rapid destruction of graphene by hydrogen and fluorine plasmas, much slower reaction kinetics between the chlorine plasma and graphene were observed, allowing for controlled chlorination. Electrical measurements on graphene sheets, graphene nanoribbons, and large graphene films grown by chemical vapor deposition showed p-type doping accompanied by a conductance increase, suggesting nondestructive doping via chlorination. Ab initio simulations were performed to rationalize the differences in fluorine, hydrogen, and chlorine functionalization of graphene.

Advanced materials for electrocatalytic and photoelectrochemical water splitting are central to the area of renewable energy. In this work, we developed a selective solvothermal synthesis of MoS(2) nanoparticles on reduced graphene oxide (RGO) sheets suspended in solution. The resulting MoS(2)/RGO hybrid material possessed nanoscopic few-layer MoS(2) structures with an abundance of exposed edges stacked onto graphene, in strong contrast to large aggregated MoS(2) particles grown freely in solution without GO. The MoS(2)/RGO hybrid exhibited superior electrocatalytic activity in the hydrogen evolution reaction (HER) relative to other MoS(2) catalysts. A Tafel slope of ∼41 mV/decade was measured for MoS(2) catalysts in the HER for the first time; this exceeds by far the activity of previous MoS(2) catalysts and results from the abundance of catalytic edge sites on the MoS(2) nanoparticles and the excellent electrical coupling to the underlying graphene network. The ∼41 mV/decade Tafel slope suggested the Volmer-Heyrovsky mechanism for the MoS(2)-catalyzed HER, with electrochemical desorption of hydrogen as the rate-limiting step.

We report a general method to graft aromatic molecules onto graphene thin film electrodes through a simple immersion process. Large-area electroactive graphene thin films grafted with methylene blue (MB) have been developed as electrocatalytic electrodes for the oxidation of β-nicotinamide adenine dinucleotide (NADH). The oxidation of NADH starts from −0.08 V (vs. Ag/AgCl) at the graphene-MB thin film electrodes, showing a decrease of 530 mV in overpotential compared to a Ti metal electrode. The graphene-MB thin films have promising applications in biosensors and biofuel cells due to their ability to promote NADH electron transfer reaction.

In our prior studies, we reported the growth of Co3O4 nanowire arrays via the ammonia-evaporation-induced growth in solution and their promising applications in a Li-ion battery and oxygen evolution. Although we had identified that the growth of Co3O4 nanowire went through the β-Co(OH)2 intermediate, the growth mechanism of Co(OH)2 nanowire was still elusive. The problem seemed to be rooted in its layered brucite crystal structure, which was not previously known to grow one-dimensionally (1D) perpendicular to the layers. In this paper, we present our recent discovery that axial screw dislocation is responsible for such longitudinal growth. Through bright-field transmission electron microscope (TEM) characterizations, the screw dislocation was directly observed as a dark-contrasted line along Co(OH)2 nanowires. Emergent spiral growth steps provide active sites for immediate adsorption of incoming molecules, resulting in a fast spiral advance rate along the c-axis of the brucite crystal. This study shows a ...

The development of highly active and stable electrocatalysts for ethanol electroxidation is of decisive importance to the successful commercialization of direct ethanol fuel cells. Despite great efforts invested over the past decade, their progress has been notably slower than expected. In this work, the facile solution synthesis of 2D PdAg alloy nanodendrites as a high-performance electrocatalyst is reported for ethanol electroxidation. The reaction is carried out via the coreduction of Pd and Ag precursors in aqueous solution with the presence of octadecyltrimethylammonium chloride as the structural directing agent. Final products feature small thickness (5-7 nm) and random in-plane branching with enlarged surface areas and abundant undercoordinated sites. They exhibit enhanced electrocatalytic activity (large specific current ≈2600 mA mgPd-1) and excellent operation stability (as revealed from both the cycling and chronoamperometric tests) for ethanol electroxidation. Control experiments show that the improvement comes from the combined electronic and structural effects.

We study the coassembly behavior of graphene oxide (GO) nanosheets and Na(0.44)MnO(2) nanowires. With the addition of GO nanosheets to the nanowire aqueous suspension, we observed the concentration enrichment and orientation alignment of nanowires at the air-water interface. The aligned nanowires can be transferred to hydrophilic substrates with their orientation parallel to the liquid-substrate contact line upon evaporation of the solvent. The underlying mechanism was studied carefully. GO nanosheets can be thought as "soft" two-dimensional macromolecules. Through hydrogen bonding and ion-dipole interactions, GO nanosheets can adsorb onto the nanowire surface and alter the surface properties. As a result, the GO-adsorbed nanowires become surface active and are enriched at the air-water interface. The adsorption of GO also increases the negative surface charge density of the nanowires and thus further stabilizes the colloidal solution. When a critical concentration is reached, the alignment of nanowires occurs according to Onsager's theory. This study brings about a new application of GO in colloidal chemistry and a novel method to achieve large-area, unidirectional alignment of nanowires.

Mesoporous Nb-doped TiO2 film was prepared by the sol−gel method on a transparent conducting FTO glass. Pt nanoparticles were impregnated in the mesoporous TiO2 support substrate and tested for the counter electrode in dye-sensitized solar cells (DSSCs). The mesoporous Pt/Nb-doped TiO2 was characterized by scanning electron microscopy and high-resolution transmission electron microscopy. The electrocatalytic activity of the Pt nanoparticles on different supports was studied by electrochemical impedance spectroscopy for the tri-iodide (I3−)/iodide (I−) redox reaction in acetonitrile, a common electrolyte solution for DSSCs. By fabricating a Pt/Nb-doped TiO2 electrode, the charge transfer resistance was reduced and the exchange current density was increased as the result of a larger active surface area of Pt in the mesoporous Nb-doped TiO2. This electrode could be used in other systems where there is a need to control the amount of Pt surface area and hamper Pt particle aggregation when operating at high te...

High aspect ratio Na0.44MnO2 nanowires with a complex one-dimensional (1-D) tunnel structure have been synthesized. We found that the reaction went through layered birnessite nanosheet intermediates, and that their conversion to the final product involved splitting of the nanosheets into nanowires. Based on our observations, a stress-induced splitting mechanism for conversion of birnessite nanosheets to Na0.44MnO2 nanowires is proposed. The final and intermediate phases show topotaxy with 〈001〉f // 〈020〉b or 〈110〉b where f represents the final Na0.44MnO2 phase and b the intermediate birnessite phase. As a result of their high surface areas, the nanowires are efficient catalysts for the oxidation of pinacyanol chloride dye.

We report an ammonia-evaporation-induced synthetic method for metal (Ni, Cu, Zn, and Cd) hydroxide/oxide nanostructures including hierarchical CuO spheres with radiating nanoplates, densely branched ZnO nanowires, Cd(OH)2 nanofibers, and Ni(OH)2 nanoplates. One important feature of this mild and surfactant-free methodology is that these nanostructures grow in a dynamic environment with the continuous decrease of pH and ammonia concentration in the solution, which is responsible for the formation of the complex architectures. The obtained Cd(OH)2 nanofibers and Ni(OH)2 nanoplates can also be converted into oxides by a subsequent thermal treatment. In addition to the synthesis and mechanism studies, we have investigated the electrochemical reactivity of the CuO spheres, CdO nanofibers, and NiO nanoplates toward lithium and demonstrated their potential application as anode materials for lithium ion batteries.

We report the high capacity and rate capability of mesoporous Co3O4 nanowire (NW) arrays as anodes in Li ion batteries. At a current of 1C, the NW arrays maintain a capacity of 700 mAh/g after 20 discharge/charge cycles. When the current is increased to 50C, 50% of the capacity can be retained. With their ease of large area synthesis and superior electrochemical properties, these Co3O4 NW arrays will be interesting for practical Li ion batteries.

Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell technology. Unfortunately, current methanol oxidation electrocatalysts fall far short of expectations and suffer from rapid activity degradation. Here we report platinum–nickel hydroxide–graphene ternary hybrids as a possible solution to this long-standing issue. The incorporation of highly defective nickel hydroxide nanostructures is believed to play the decisive role in promoting the dissociative adsorption of water molecules and subsequent oxidative removal of carbonaceous poison on neighbouring platinum sites. As a result, the ternary hybrids exhibit exceptional activity and durability towards efficient methanol oxidation reaction. Under periodic reactivations, the hybrids can endure at least 500,000 s with negligible activity loss, which is, to the best of our knowledge, two to three orders of magnitude longer than all available electrocatalysts., Efficient electrocatalysts are critical for the development of methanol fuel cell technology but most catalysts reported to date suffer from low durability. Here, the authors report platinum-nickel hydroxide-graphene ternary hybrid catalysts with durability extended by two to three orders of magnitude.

For solving the large-scale job shop scheduling problems considering flexible routings with the characteristics of process planning and scheduling optimization, a hierarchical coordination optimization model based on analytical target cascading is proposed in this paper, which is divided into three sub-layers. The process planning layer is for optimal processing routes of all jobs, and multiple manufacturing units is formed by clustering all machines based on factor analysis method in the unit planning layer, and then the optimal scheduling solutions of jobs in each unit is obtained by adopting the improved genetic algorithm respectively in the job scheduling layer, which then gives feedback to the upper layer and repeatedly coordinates to obtain the global optimal solution. Finally, a typical computational experiment comparatively demonstrates the validity of the proposed model and algorithm, showing its efficient advantage in solving the large-scale job shop scheduling problems with flexible routings.