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We demonstrate the design of graphene-supported dual atom catalysts (DACs) for the four-electron oxygen reduction reaction (ORR), by utilizing the non-bonding interaction of counterpart metals (M) that synergistically tune the electronic properties and catalytic activity of the Fe active site in FeMN₆-DAC and FeMN₈-DAC systems, where M stands for Fe, Co, Ni, Cu, and Zn. More specifically, for Fe-M distances below 15 Å, the non-bonding interaction is significant, making the system act as the DAC. We predicted that FeNiN₆-DAC and FeNiN₈-DAC exhibit a low ORR overpotential (η^(ORR)) of 0.28 V and 0.47 V, respectively, which are at the summits of volcano plots. This low η^(ORR) originates from the high Bader charge transfer coupled with high spin density at the Fe site in both the FeNiN₆-DAC and FeNiN₈-DAC systems, which weakens the adsorption of OH* intermediate while enhancing its desorption to H₂O. Guided by these density functional theory (DFT) computational results, we synthesized FeCoN₈-DAC and FeNiN₈-DAC along with N-doped graphene and confirmed their structures with scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge structure (XANES), extended X-ray absorption fine structure (EXAFS), and electron spin resonance (ESR). We verify experimentally the catalytic activities and find that FeNiN₈-DAC has the low experimental overpotential of 0.39 V with a Tafel slope of 47 mVdec⁻¹. Based on these results, we propose a DFT-guided strategy to tune the charge transfer and spin population of the active site toward designing DACs for electrochemical ORR.

Single-photon emitters (SPEs) in hexagonal boron nitride (hBN) are promising candidates for quantum light generation. Despite this, techniques to control the formation of hBN SPEs down to the monolayer limit are yet to be demonstrated. Recent experimental and theoretical investigations have suggested that the visible wavelength single-photon emitters in hBN originate from carbon-related defects. Here, we demonstrate a simple strategy for controlling SPE creation during the chemical vapor deposition growth of monolayer hBN via regulating surface carbon concentration. By increasing the surface carbon concentration during hBN growth, we observe increases in carbon doping levels by 2.4-fold for B-C bonds and 1.6-fold for N-C bonds. For the same samples, we observe an increase in the SPE density from 0.13 to 0.30 emitters/μm2. Our simple method enables the reliable creation of hBN SPEs in monolayer samples for the first time, opening the door to advanced two-dimensional (2D) quantum state engineering.

Machine learning (ML) integrated density functional theory (DFT) calculations have recently been used to accelerate the design and discovery of heterogeneous catalysts such as single atom catalysts (SACs) through the establishment of deep structure–activity relationships.

Na metal is a promising candidate as anode material owing to its high theoretical energy density and abundance on earth, but suffers from dendrite growth, extremely large volume change, and poor Coulombic efficiency. Herein, a low-cost and effective strategy is developed to discourage the dendrite growth by in situ formation of an artificial NaF-rich protective layer on Na metal. The protective layer facilitates the formation of highly stable, NaF-rich solid electrolyte interphase (SEI) capable of preventing continuous electrolyte depletion during charge/discharge cycles. The depth profiling experiment confirms functional gradient of SEI through its thickness with wealthier NaF species towards the Na metal. The symmetric cells assembled using the Na anode with a protective layer exhibit excellent cyclic stability with low overpotentials of 8, 50, and 70 mV, at areal currents of 1, 5 and 10 mA cm−2, respectively, thanks to its high dendrite suppression ability as proven by theoretical calculations. The full battery prepared with a Na3V2(PO4)3 cathode delivers 99% retention of Coulombic efficiency after 400 and 600 cycles at 1C in ether- and carbonate-based electrolytes, respectively. The SEI layer design strategy presented here can shed some important insights into the development of high-performance dendrite-free Na metal batteries and interface engineering for solid electrolytes.

Two-dimensional (2D) hexagonal boron nitride (hBN), due to its extraordinary thermal, chemical, and optical properties, has arisen as an enticing material for the research community to explore for various applications, including the use of site defects in hBN as single photon emitters (SPEs). In this review, we systematically summarize recent advanced strategies towards the controllable synthesis of 2D hBN using chemical vapor deposition, towards a full control of the domain size, orientation, morphology, layer number, and stacking order, etc. Moreover, we review the underlying mechanisms for single photon emission (SPE) in hBN and methods to selectively generate and tune the SPEs. Defects (e.g., carbon substituted defects) are discussed for the potential use as emission sites. We finally give an outlook of future challenges and opportunities on desirable hBN synthesis and further investigation of SPEs in hBN, targeting to utilize hBN as single photon emitters in an industrial scale.

We demonstrate the use of the machine learning (ML) tools to rapidly and accurately predict the electric field as a guide for designing core-shell Au-silica nanoparticles to enhance

Low-temperature synthesis of large-area graphene films by chemical vapor deposition (CVD) method has attracted extensive research interests owing to their extraordinary potential applications. Current reports on the low-temperature graphene growth usually involve catalytic metal substrates, which exceedingly impedes the direct use of graphene in nanoelectronic fabrications. In this project, we design a space-confined growth chamber utilizing two SiO2/Si chips. The bottom chip loading pre-transferred graphene flakes accommodates the growth of second monolayer graphene, with a tellurium (Te) vapor assisted growth process. Polymethylmethacrylate (PMMA) residues introduced from the transferred graphene substrate is employed as the solid carbon source. Further, the numerical simulation results prove that the high concentration of active carbons in the confined space plays a vital role in this growth process. Density functional theory (DFT) calculations reveal that, Te atoms prefer to bond with the edge carbons of small graphene flakes and serve as an effective catalyst, which helps to grow small graphene flakes by reducing their energy of formation. The successful growth can provide the high-quality monolayer graphene grains at the low temperature (∼350 °C). This facile strategy promises the mass production of graphene at mild conditions and low costs, which contributes to the green chemistry in future.

Diabetic patients suffer from peripheral nerve injury with slow and incomplete regeneration owing to hyperglycemia and microvascular complications. This study develops a graphene-based nerve guidance conduit by incorporating natural double network hydrogel and a neurotrophic concentration gradient with non-invasive treatment for diabetics. GelMA/silk fibroin double network hydrogel plays quadruple roles for rapid setting/curing, suitable mechanical supporting, good biocompatibility, and sustainable growth factor delivery. Meanwhile, graphene mesh can improve the toughness of conduit and enhance conductivity of conduit for regeneration. Here, novel silk tapes show quick and tough adhesion of wet tissue by dual mechanism to replace suture step. The in vivo results demonstrate that gradient concentration of netrin-1 in conduit have better performance than uniform concentration caused by chemotaxis phenomenon for axon extension, remyelination, and angiogenesis. Altogether, GelMA/silk graphene conduit with gradient netrin-1 and dry double-sided adhesive tape can significantly promote repairing of peripheral nerve injury and inhibit the atrophy of muscles for diabetics.

The gold standard treatment for peripheral nerve injuries (PNIs) is the autologous graft, while it is associated with the shortage of donors and results in major complications. In the present study, we engineer a graphene mesh-supported double-network (DN) hydrogel scaffold, loaded with netrin-1. Natural alginate and gelatin-methacryloyl entangled hydrogel that is synthesized via fast exchange of ions and ultraviolet irradiation provide proper mechanical strength and excellent biocompatibility and can also serve as a reservoir for netrin-1. Meanwhile, the graphene mesh can promote the proliferation of Schwann cells and guide their alignments. This approach allows scaffolds to have an acceptable Young's modulus of 725.8 ± 46.52 kPa, matching with peripheral nerves, as well as a satisfactory electrical conductivity of 6.8 ± 0.85 S/m. In addition, netrin-1 plays a dual role in directing axon pathfinding and neuronal migration that optimizes the tube formation ability at a concentration of 100 ng/mL. This netrin-1-loaded graphene mesh tube/DN hydrogel nerve scaffold can significantly promote the regeneration of peripheral nerves and the restoration of denervated muscle, which is even superior to autologous grafts. Our findings may provide an effective therapeutic strategy for PNI patients that can replace the scarce autologous graft.

The further improvement of sodium ion batteries requires the elucidation of the mechanisms pertaining to reversibility, which allows the novel design of the electrode structure. Here, through a hydrogel-embedding method, we are able to confine the growth of few-layer SnS2 nanosheets between a nitrogen- and sulfur-doped carbon nanotube (NS-CNT) and amorphous carbon. The obtained carbon-sandwiched SnS2 nanosheets demonstrate excellent sodium storage properties. In operando small-angle X-ray scattering combined with the ex situ X-ray absorption near edge spectra reveal that the redox reactions between SnS2/NS-CNT and the sodium ion are highly reversible. On the contrary, the nanostructure evolution is found to be irreversible, in which the SnS2 nanosheets collapse, followed by the regeneration of SnS2 nanoparticles. This work provides operando insights into the chemical environment evolution and structure change of SnS2-based anodes, elucidating its reversible reaction mechanism, and illustrates the significance of engineered carbon support in ensuring the electrode structure stability.

BackgroundAlthough clozapine is an effective option for treatment-resistant schizophrenia (TRS), there are still 1/3 to 1/2 of TRS patients who do not respond to clozapine. The main purposes of this randomized, double-blind, placebo-controlled trial was to explore the amisulpride augmentation efficacy on the psychopathological symptoms and cognitive function of CTRS patients. MethodsA total of 80 patients were recruited and randomly assigned to receive an initial clozapine plus amisulpride or clozapine plus placebo. Positive and Negative Syndrome Scale (PANSS), Scale for the Assessment of Negative Symptoms (SANS), Clinical Global Impression (CGI) scale scores, Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Treatment Emergent Symptom Scale (TESS), laboratory measurements and electrocardiograms (ECG) were performed at baseline, week 6, and week 12. ResultsCompared with clozapine plus placebo group, clozapine plus amisulpride had lower PANSS total score, positive subscore and general psychopathology subscore at week 6 and week 12 (all p Bonferroni< 0.01). Furthermore, compared with clozapine plus placebo group, clozapine plus amisulpride showed improved RBANS language score at week 12 (p Bonferroni< 0.001). Clozapine plus amisulpride group had a higher treatment response rate (p = 0.04), lower scores of CGI severity (CGI-S) and CGI efficacy (CGI-E) at week 6 and week 12 than clozapine plus placebo (all p Bonferroni< 0.05). There were no differences in BMI, QT intervals or laboratory measurements between the groups. Our results demonstrate that amisulpride augmentation therapy can safely improve the psychiatric symptoms and cognitive performance of CTRS patients. ConclusionsOur study indicates that amisulpride augmentation therapy has important clinical significance for the treatment of CTRS to improve clinical symptoms and cognitive function with tolerability and safety.Trial registrationClinicaltrials.gov identifier- NCT03652974. Registered 31 August 2018, https://clinicaltrials.gov/ct2/show/NCT03652974

Background Increasing evidence indicates that dysregulated TNF-α and oxidative stress (OxS) contribute to the pathophysiology of schizophrenia. Additionally, previous evidence has demonstrated sex differences in many aspects of schizophrenia including clinical characteristics, cytokines, and OxS markers. However, to the best of our knowledge, there is no study investigating sex differences in the association between TNF-α, the OxS system, and their interaction with clinical symptoms in schizophrenia patients, especially in first-episode drug-naïve (FEDN) patients. Methods A total of 119 FEDN schizophrenia patients and 135 healthy controls were recruited for this study. Serum TNF-α, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) were measured. The Positive and Negative Syndrome Scale (PANSS) was applied to evaluate psychotic symptoms. Two-way ANOVA, partial correlation analysis, and multivariate regression analysis were performed. Results A sex difference in MDA levels was demonstrated only in healthy controls (F = 7.06, pBonferroni = 0.045) and not seen in patients. Furthermore, only male patients had higher MDA levels than male controls (F = 8.19, pBonferroni = 0.03). Additionally, sex differences were observed in the association of TNF-α and MDA levels with psychotic symptoms (all pBonferroni < 0.05). The interaction of TNF-α and MDA was only associated with general psychopathology symptom in male patients (B = − 0.07, p = 0.02). Conclusion Our results demonstrate the sex difference in the relationship between TNF-α, MDA, and their interaction with psychopathological symptoms of patients with schizophrenia.

To enhance interlayer lithium diffusion, we engineer electrodes consisting of epitaxially grown ReSe2 nanosheets by chemical vapor deposition, supported on three-dimensional (3D) graphene foam, taking advantage of its weak van der Waals coupling and anisotropic crystal structure. We further demonstrate its excellent performance as the anode for lithium-ion battery and catalyst for hydrogen evolution reaction (HER). Density functional theory calculation reveals that ReSe2 exhibits a low energy barrier for lithium (Li) interlayer diffusion because of negligible interlayer coupling and anisotropic structure with low symmetry that creates additional adsorption sites and leads to a reduced diffusion barrier. Benefitting from these properties, the 3D ReSe2/graphene foam electrode displays excellent cycling and rate performance with 99.6% capacity retention after 350 cycles and a capacity of 327 mA h g-1 at the current density of 1000 mA g-1. Additionally, it has exhibited a high activity for HER, in which an exchange current density of 277.8 μA cm-2 is obtained and only an overpotential of 106 mV is required to achieve a current density of -10 mA cm-2. Our work provides a fundamental understanding of the interlayer diffusion of Li in transition-metal dichalcogenide (TMD) materials and acts as a new tool for designing a TMD-based catalyst.

For lithium-sulfur batteries (LSBs), the dissolution of lithium polysulfide and the consequent "shuttle effect" remain major obstacles for their practical applications. In this study, we designed a new cathode material comprising MoSe2/graphene to selectively adsorb polysulfides on the selenium edges and thus to mitigate their dissolution. More specifically, few-layered MoSe2 was first grown on nitrogen-doped reduced graphene oxide (N-rGO) using the chemical vapor deposition method and then infiltrated with sulfur as the cathode for LSBs. An initial capacity of 1028 mA h g-1 was achieved for S/MoSe2/N-rGO at 0.2 C, higher than 981 and 405.1 mA h g-1 for pure graphene and sulfur, respectively, along with enhanced cycling durability and rate capability. Moreover, the density functional theory simulation, in addition to the experimental adsorption test, X-ray photoelectron spectroscopy analysis, and transmission electron microscopy technique, reveals the dual roles that MoSe2 plays in improving the performance of LSBs by functioning as the binding sites for lithium polysulfides and as the platform that enables fast Li-ion diffusion by reducing its diffusion barrier. The reported finding suggests that the transition-metal selenides could be an efficient alternative material as the cathode for LSBs.

The rhenium-based transition metal dichalcogenides (TMDs), as new members in the TMDs family, have raised great interests recently. Due to the anisotropic structure and unique photoelectric properties, they have potential applications for electrochemical energy conversion and storage. In this work, we performed density functional theory (DFT) calculations on pristine 1T′-ReSe2 toward hydrogen evolution reaction (HER). The results indicated that the Gibbs free energy of the 1T′-ReSe2 edge site for HER could be as small as 0.01 eV, superior to other reported TMDs. Experimentally, we developed a strategy to fabricate sub-5 nm sized 1T′-ReSe2 nanoflakes on carbon nanotubes. Such a small size for the nanoflakes brought abundant edge exposure, which boosted the catalytic activity in the HER. Specifically, the 1T′-ReSe2 nanoflakes needed only 23 and 60 mV overpotentials to achieve −1 and −10 mA cm−2 current densities, along with a low Tafel slope of 37 mV dec−1 and a high exchange current density of 0.3 mA cm−2. The edge-rich and layered 1T′-ReSe2 was also explored as an anode for sodium ion battery. The in operando X-ray absorption near edge structure (XANES) technique was applied to investigate the TMD behavior in real-time during the sodiation/desodiation process. The in situ results revealed that the nanosized 1T′-ReSe2 is electrchemically reversible during discharge/charge cycles. The electrochemical test results demonstrated that 1T′-ReSe2 could be a promising anode material for alkaline batteries.

In dissolution test, the surfactant sodium lauryl sulfate (SLS) is usually added to increase the dissolution of insoluble drugs and achieve the sink condition. However, the current study found that 0.1 % SLS would significantly decrease the dissolution of crystalline lurasidone hydrochloride (LH, a BCS Ⅱ drug). The aim of this study was to clarify the mechanism of this unexpected phenomenon and explore a strategy for mitigating the negative effect of SLS on the dissolution of LH. Sample characterizations (such as PLM, DSC, PXRD, IR and NMR) confirmed that the insoluble single-phase amorphous LH-SLS complex (with a single T

Atomically thin monolayer semiconducting transition metal dichalcogenides (TMDs), exhibiting direct band gap and strong light-matter interaction, are promising for optoelectronic devices. However, an efficient band alignment engineering method is required to further broaden their practical applications as versatile optoelectronics. In this work, the band alignment of two vertically stacked monolayer TMDs using the chemical vapor deposition (CVD) method is effectively tuned by two strategies: 1) formulating the compositions of MoS

Conventional absorbents for hemoperfusions suffer from low efficiency and slow absorption with numerous side effects. In this research, we developed cellulose acetate (CA) functionalized graphene oxide (GO) beads (∼1.5-2 mm) that can be used for direct hemoperfusion, aiming at the treatment of kidney dysfunction. The CA-functionalized GO bead facilitates adsorption of toxins with high biocompatibility and high-efficiency of hemoperfusion while maintaining high retention for red blood cell, white blood cells, and platelets. Our in vitro results show that the toxin concentration for creatinine reduced from 0.21 to 0.12 μM (p < 0.005), uric acid from 0.31 to 0.15 mM (p < 0.005), and bilirubin from 0.36 to 0.09 mM (p < 0.005), restoring to normal levels within 2 h. Our in vivo study on rats (Sprague-Dawley, n = 30) showed that the concentration for creatinine reduced from 83.23 to 54.87 μmol L-1 (p < 0.0001) and uric acid from 93.4 to 54.14 μmol L-1 (p < 0.0001), restoring to normal levels within 30 min. Results from molecular dynamics (MD) simulations using free-energy calculations reveal that the presence of CA on GO increases the surface area for adsorption and enhances penetration of toxins in the binding cavities because of the increased electrostatic and van der Waals force (vdW) interactions. These results provide critical insight to fabricate graphene-based beads for hemoperfusion and to have the potential for the treatment of blood-related disease.

BackgroundIncreasing evidence indicates that dysregulated TNF-α and oxidative stress (OxS) contribute to the pathophysiology of schizophrenia. Additionally, previous evidence has demonstrated sex differences in many aspects of schizophrenia including clinical characteristics, cytokines and OxS markers. However, to the best of our knowledge, there is no study investigating sex differences in the association between TNF-α, the OxS system, and their interaction with clinical symptoms in schizophrenia patients, especially in first-episode drug-naïve (FEDN) patients. MethodsA total of 119 FEDN schizophrenia patients and 135 healthy controls were recruited for this study. Serum TNF-α, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) were measured. The Positive and Negative Syndrome Scale (PANSS) was applied to evaluate psychotic symptoms. Two-way ANOVA, partial correlation analysis and multivariate regression analysis were performed. ResultsA sex difference in MDA levels was demonstrated only in healthy controls (F = 7.06, p Bonferroni = 0.045) and not seen in patients. Furthermore, only male patients had higher MDA levels than male controls (F = 8.19, p Bonferroni = 0.03). Additionally, sex differences were observed in the association of TNF-α and MDA levels with psychotic symptoms (all pBonferroniConclusionOur results demonstrate the sex difference in the relationship between TNF-α, MDA, and their interaction with psychopathological symptoms of patients with schizophrenia.

We developed a general platform for the fabrication of transition metal oxide nanoparticles supported by a graphene foam (GF) by first coating it with a methacrylated gelatin (GelMA) hydrogel, which served as a 3D matrix for nanoparticle dispersion. The engineered GelMA/GF matrix was hydrophilic with good mechanical strength and high conductivity, therefore providing a good platform for the dispersion of a variety of metal/oxide precursors. Due to this platform, well-dispersed Co3O4 nanoparticles with the smallest size of 3 nm assembled on the nitrogen-doped graphene foam (Co3O4/NGF). The crystalline transformation from a CoCl2[H2O]2 precursor to Co3O4 was revealed by in operando X-ray diffraction and absorption techniques. After applying Co3O4/NGF as a free-standing electrocatalyst for water splitting, the nanoparticles of size 3 nm exhibited optimal catalytic activity in alkaline media; the corresponding cell could promote water splitting at a current density of 10 mA cm-2 with only 1.63 V and exhibited excellent stability in a 25 h long-term operation. Our results demonstrate that the GelMA hydrogel-coated 3D graphene foam can be a promising platform for the design and fabrication of graphene-based multifunctional materials.

With the increasing demand for wearable and implantable electronics, structured sensors with exceptional performance in sensitivity, stretchability, biocompatibility, and adhesion to the biological surfaces have become essential. Here, we report a novel graphene strain sensor, whose structure contains a carefully selected graphene foam (GF) and polyacrylamide/calcium-alginate (PAM/CA) double network hydrogel coupled with chitosan, can meet the above requirements to the maximum extent. Taking the advantage of the excellent electrical properties of graphene and the mechanical properties of hydrogel, this strain sensor can measure an exceptionally wide range of strain up to 500%, which allows us to monitor and distinguish almost all human body motions, with a gauge factor of ∼1800, which is up to 3 orders of magnitude larger than the 0.1–1000 value reported previously. The device also shows high stability and excellent durability for 1000 cycles. Most importantly, the chitosan-bridge and skin-like elastic modulus of 8–90 kPa allow conformal adhesion between the skin and hydrogel, with the adhesion energy of ∼200 J m−2. Moreover, this structured sensor is highly biocompatible and can be implanted in vivo, and has further potential in clinical applications.

Artificial water diversion project has been increasingly implemented to control eutrophication and alleviate water shortage of lakes. Water diversion can affect the biogeochemical cycles, however, carbon dioxide (CO2) sensitivity in lakes to water diversion was poorly understood. This study addressed the issue based on the famous Water Diversion project from the Yangtze River to eutrophic Lake Taihu, which has been carried out regularly since 2002 in China. The partial pressure of CO2 (pCO2) at two regions of the eutrophic lake, water-receiving Gonghu Bay and non-water-receiving Central Zone, was investigated over 16 years (2002–2017) field measurement with high sampling frequency. Results showed the river-to-lake water diversion decreased phytoplankton biomass, increased nutrient loadings, and significantly elevated the pCO2 and associated CO2 emission. Meanwhile, the water diversion project accounted for the notable CO2 spatial heterogeneity between regions and within region. However, weak CO2 seasonal variability was observed at Gonghu Bay during water diversion period. The estimated CO2 emission flux increased averagely by 54% due to water diversion, primarily resulting from phytoplankton dilution, nutrient enrichment, and external CO2 input. Water diversion and ammonia nitrogen together explained 69% of interannual variability pCO2 at Gonghu Bay, implying water diversion should be considered to better understanding the contribution of lake CO2 emissions to C budget under a changing environment. These findings were expected to serve as a reference to evaluate the water diversion effects, further study should focus on the sources of the excess CO2 to make the project a CO2-neutral option.

The edge site of two-dimensional (2D) transition metal dichalcogenides (TMDs) is active towards the hydrogen evolution reaction (HER). Herein, a feasible synthesis of sub-100 nm molybdenum/tungsten diselenide [Mo(1−x)WxSe2] crystals is described. The abundant edge exposure and heteroatom-doping synergistically boost the catalysis of HER by this material. In this work, sub-100 nm Mo(1−x)WxSe2 single crystals were grown on a nitrogen-doped multiwall carbon nanotube before being applied as HER electrocatalysts. At x = 0.13 ± 0.02, the Mo(1−x)WxSe2 shows optimal HER catalytic performance with low overpotentials (70 and 129 mV) required to achieve current densities of −1 and −10 mA cm−2, respectively, along with a Tafel slope of 53.6 mV dec−1 and an exchange current density of 49.5 μA cm−2. Density functional theory (DFT) calculations indicate that the Gibbs free energy of the HER process at the edge site of the crystals reaches a minimum value of 0.06 eV, which is lower than when the reaction is catalysed on Pt active sites. This study provides a general approach to increasing the edge proportion of the catalyst material and activating the terrace of the 2D materials for catalysis, which may be of benefit to the design and fabrication of other TMDs-based compounds.

To enhance interlayer lithium diffusion, we engineer electrodes consisting of epitaxially grown ReSe

For lithium-sulfur batteries (LSBs), the dissolution of lithium polysulfide and the consequent "shuttle effect" remain major obstacles for their practical applications. In this study, we designed a new cathode material comprising MoSe

We developed a general platform for the fabrication of transition metal oxide nanoparticles supported by a graphene foam (GF) by first coating it with a methacrylated gelatin (GelMA) hydrogel, which served as a 3D matrix for nanoparticle dispersion. The engineered GelMA/GF matrix was hydrophilic with good mechanical strength and high conductivity, therefore providing a good platform for the dispersion of a variety of metal/oxide precursors. Due to this platform, well-dispersed Co3O4 nanoparticles with the smallest size of 3 nm assembled on the nitrogen-doped graphene foam (Co3O4/NGF). The crystalline transformation from a CoCl2[H2O]2 precursor to Co3O4 was revealed by in operando X-ray diffraction and absorption techniques. After applying Co3O4/NGF as a free-standing electrocatalyst for water splitting, the nanoparticles of size 3 nm exhibited optimal catalytic activity in alkaline media; the corresponding cell could promote water splitting at a current density of 10 mA cm-2 with only 1.63 V and exhibited excellent stability in a 25 h long-term operation. Our results demonstrate that the GelMA hydrogel-coated 3D graphene foam can be a promising platform for the design and fabrication of graphene-based multifunctional materials.

With large scale construction of UHV AC / DC hybrid power grid and the "Big Run" system, the service area of the power network dispatch control system is expanding rapidly. The system is facing new challenges as the data source increased, data type diverted, data size and workload increased dramatically. There is a great demand on storing and retrieving of multi-source massive data. The existing system is inadequate on unified storage and rapid retrieve of massive data, thence the research on unified storage management and retrieve of massive big data for grid dispatch control system is on urgent demand.

Bamboo represents the only major lineage of grasses that is native to forests and is one of the most important non-timber forest products in the world. However, no species in the Bambusoideae subfamily has been sequenced. Here, we report a high-quality draft genome sequence of moso bamboo (P. heterocycla var. pubescens). The 2.05-Gb assembly covers 95% of the genomic region. Gene prediction modeling identified 31,987 genes, most of which are supported by cDNA and deep RNA sequencing data. Analyses of clustered gene families and gene collinearity show that bamboo underwent whole-genome duplication 7-12 million years ago. Identification of gene families that are key in cell wall biosynthesis suggests that the whole-genome duplication event generated more gene duplicates involved in bamboo shoot development. RNA sequencing analysis of bamboo flowering tissues suggests a potential connection between drought-responsive and flowering genes.