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Platinum is the most efficient catalyst for hydrogen evolution reaction in acidic conditions, but its widespread use has been impeded by scarcity and high cost. Herein, Pt atomic clusters (Pt ACs) containing Pt-O-Pt units were prepared using Co/N co-doped carbon (CoNC) as support. Pt ACs are anchored to single Co atoms on CoNC by forming strong interactions. Pt-ACs/CoNC exhibits only 24 mV overpotential at 10 mA cm−2 and a high mass activity of 28.6 A mg−1 at 50 mV, which is more than 6 times higher than commercial Pt/C with any Pt loadings. Spectroscopic measurements and computational modeling reveal the enhanced hydrogen generation activity attributes to the charge redistribution between Pt and O atoms in Pt-O-Pt units, making Pt atoms the main active sites and O linkers the assistants, thus optimizing the proton adsorption and hydrogen desorption. This work opens an avenue to fabricate noble-metal-based ACs stabilized by single-atom catalysts with desired properties for electrocatalysis.

Three-dimensional Prussian blue (PB) nanostructures was obtained via a one-step hydrothermal method. Subsequently, two-dimensional tin disulfide (SnS2) nanosheets were grown onto PB through a facile hydrothermal synthesis. The as prepared SnS2/PB is further employed as the anode of sodium ion batteries (SIBs). SnS2/PB nanoarchitecture delivers a specific capacity of 725.7 mAh-g−1 at 50 mA·g−1. When put through more than 200 cycles, it achieved a stable cycling capacity of 400 mAh·g−1 at 200 mA·g−1. The stable Na+ storage properties of SnS2/PB was attributed to the synergistic effect among the conductive PB carbon, used as the template in this work. These results obtained potentially paves the way for the development of excellent electrochemical performance with stable performance of SIBs.

Highlights Recent advances of non-metal nanocarbon materials for electrocatalytic oxygen reduction reaction (ORR) are comprehensively summarized in terms of co-engineering of heteroatom doping and defect inducing.The characteristics, ORR performance, and the related mechanism of non-metal nanocarbon are emphatically analyzed and discussed.The current issues and perspectives in developing carbon-based electrocatalysts from both of heteroatom doping and defect engineering are pointed out and proposed., Exploring low-cost and earth-abundant oxygen reduction reaction (ORR) electrocatalyst is essential for fuel cells and metal–air batteries. Among them, non-metal nanocarbon with multiple advantages of low cost, abundance, high conductivity, good durability, and competitive activity has attracted intense interest in recent years. The enhanced ORR activities of the nanocarbons are normally thought to originate from heteroatom (e.g., N, B, P, or S) doping or various induced defects. However, in practice, carbon-based materials usually contain both dopants and defects. In this regard, in terms of the co-engineering of heteroatom doping and defect inducing, we present an overview of recent advances in developing non-metal carbon-based electrocatalysts for the ORR. The characteristics, ORR performance, and the related mechanism of these functionalized nanocarbons by heteroatom doping, defect inducing, and in particular their synergistic promotion effect are emphatically analyzed and discussed. Finally, the current issues and perspectives in developing carbon-based electrocatalysts from both of heteroatom doping and defect engineering are proposed. This review will be beneficial for the rational design and manufacturing of highly efficient carbon-based materials for electrocatalysis.

In this work, a simple electrical conductivity measurement technique is applied to effectively determine the boron concentration in the aqueous solution based on the ionized complex formed between boron species and vitamin B6, which can be easily detected and accurately measured using a conductivity meter. The log of boron concentration is linearly correlated with the log of conductivity change within the range of 0–550 mg/L boron content. The correlation coefficient (R2) is up to 0.99882. The reproducibility is 100%. The methods can be directly applicable in deionization water or diluted seawater within diluted factor 34 times or higher (0–1600 us/cm conductivity range). This work provides a cost-effective technology for the boron measurement and will be of great industrial importance in boron measurement field.

Modifying a polypropylene (PP) separator with a polysulfide barrier layer can improve the cycling performance of lithium–sulfur (Li–S) batteries. However, conventional slurry-coating- and vacuum-filtration-designed barriers usually show poor particle connection and require extra binder. Herein, we propose a facile in situ growth method and a subsequent compression strategy to design multifunctional NiCo2S4 (NiCoS) nanosheet arrays on a PP membrane for high-performance Li–S batteries. The in situ grown NiCoS nanosheet arrays are interconnected, conductive and closely adhered to the PP membrane without using any binder. After mechanical compression treatment, the overall NiCoS film is compacted, lightweight (0.148 mg cm−2) and ultrathin (0.8 μm). Density functional theory calculations combined with adsorption and diffusion tests prove that the NiCoS nanosheets have highly efficient physical/chemical entrapping capabilities for preventing polysulfide shuttling. Moreover, in situ electrochemical impedance spectroscopy demonstrated that the NiCoS barrier could efficiently suppress polysulfide diffusion and concurrently facilitate redox reactions. When applying this multifunctional separator, a sulfur/carbon nanotube (S/CNT) cathode with high sulfur content (75 wt%) delivers significantly improved long-term cycling performance, with 0.056% capacity decay per cycle over 500 cycles. This work opens up new opportunities to design multifunctional separators by an in situ growth strategy for high-performance Li–S batteries. Nanomaterials that retain their porous frameworks even after being crushed can help experimental lithium batteries avoid premature failure. While high-capacity lithium–sulfur batteries are promising for the electric vehicle market, their electrodes normally need to be wrapped in heavy barrier layers to prevent sulfur atoms from moving during recharging. Hui Ying Yang from the Singapore University of Technology and Design and co-workers have now designed a lightweight barrier with natural sulfur-capturing capabilities. The team grew thin nanosheets of nickel–cobalt–sulfur crystals directly onto a polypropylene membrane, and then mechanically compressed the film with rollers. Characterization experiments revealed the nanosheet film had abundant bonding sites for sulfur atoms within its pores, and a compact structure that inhibited diffusion. Batteries containing the new barrier had improved long-term cycling performance compared with unmodified lithium–sulfur devices. A facile in situ growth and subsequent compression strategy has been proposed to modify the separator. The in situ grown barrier layer is compact, lightweight and thin, exhibiting efficient physical/chemical entrapping capability on preventing the polysulfide shuttling. Applying this multi-functional separator, the CNT/S cathode with high sulfur content (75 wt%) delivers significantly improved long-term cycling performance with 0.056% capacity decay per cycle over 500 cycles.

Graphene and hexagonal boron nitride (h-BN), as typical two-dimensional (2D) materials, have long attracted substantial attention due to their unique properties and promise in a wide range of applications. Although they have a rather large difference in their intrinsic bandgaps, they share a very similar atomic lattice; thus, there is great potential in constructing heterostructures by lateral stitching. Herein, we present the in situ growth of graphene and h-BN lateral heterostructures with tunable morphologies that range from a regular hexagon to highly symmetrical star-like structure on the surface of liquid Cu. The chemical vapor deposition (CVD) method is used, where the growth of the h-BN is demonstrated to be highly templated by the graphene. Furthermore, large-area production of lateral G-h-BN heterostructures at the centimeter scale with uniform orientation is realized by precisely tuning the CVD conditions. We found that the growth of h-BN is determined by the initial graphene and symmetrical features are produced that demonstrate heteroepitaxy. Simulations based on the phase field and density functional theories are carried out to elucidate the growth processes of G-h-BN flakes with various morphologies, and they have a striking consistency with experimental observations. The growth of a lateral G-h-BN heterostructure and an understanding of the growth mechanism can accelerate the construction of various heterostructures based on 2D materials. Graphene flakes can now be co-assembled with another nanomaterial into centimeter-scale sheets with promising optical and electrical properties. Hexagonal boron nitride (h-BN) is a light-responsive ceramic that has a similar 2D atomic lattice to high-conductivity graphene. A team led by Hui Ying Yang at the Singapore University of Technology and Design and Feng Ding from the Institute for Basic Science in Ulsan, South Korea, have now used liquefied copper as a confined growth environment to combine these two compounds. Exposing copper held at 1100 °C to methane vapors catalyzed the growth of tiny 2D graphene flakes in a thin surface region. Subsequent addition of boron nitride prompted lateral growth of h-BN crystals around the graphene flake edges. The researchers showed that by tweaking the chemical vapor conditions large-area graphene/h-BN structures across the whole substrate could be produced. In this work, the large-scale growth of lateral G-h-BN heterostructure with controlled morphology together with growth mechanism have been studies. 2D h-BN lateral heterostructures with tunable morphology ranging from regular hexagon to highly symmetrical star-like is demonstrated for the first time on a liquid Cu surface by chemical vapor deposition (CVD) approach. Morphology evolution of the G-h-BN heterostructure as a function of gas flow rate and growth time is directly observed and extensively simulated based on phase field and density functional theory calculations.

Improving the cycling stability of metal sulfide-based anode materials at high rate is of great significance for advanced sodium ion batteries. However, the sluggish reaction kinetics is a big obstacle for the development of high-performance sodium storage electrodes. Herein, we have rationally engineered the heterointerface by designing the Fe1−xS/MoS2 heterostructure with abundant “ion reservoir” to endow the electrode with excellent cycling stability and rate capability, which is proved by a series of in and ex situ electrochemical investigations. Density functional theory calculations further reveal that the heterointerface greatly decreases sodium ion diffusion barrier and facilitates charge-transfer kinetics. Our present findings not only provide a deep analysis on the correlation between the structure and performance, but also draw inspiration for rational heterointerface engineering toward the next-generation high-performance energy storage devices.

Flexible electrochemical energy storage devices have attracted extensive attention as promising power sources for the ever-growing field of flexible and wearable electronic products. However, the rational design of a novel electrode structure with a good flexibility, high capacity, fast charge–discharge rate and long cycling lifetimes remains a long-standing challenge for developing next-generation flexible energy-storage materials. Herein, we develop a facile and general approach to three-dimensional (3D) interconnected porous nitrogen-doped graphene foam with encapsulated Ge quantum dot/nitrogen-doped graphene yolk-shell nano architecture for high specific reversible capacity (1,220 mAh g−1), long cycling capability (over 96% reversible capacity retention from the second to 1,000 cycles) and ultra-high rate performance (over 800 mAh g−1 at 40 C). This work paves a way to develop the 3D interconnected graphene-based high-capacity electrode material systems, particularly those that suffer from huge volume expansion, for the future development of high-performance flexible energy storage systems., The development of materials for energy storage hinges on the design of electrodes with large capacity, flexibility, fast charge–discharge rate and long cycling lifetime. Here, the authors develop electrodes based on nitrogen doped graphene with encapsulated Ge quantum dots with yolk-shell architecture.

The optimum glass formers in ternary La-TM-Al (TM = Co, Ni, Cu) alloys were pinpointed at alloys La69Co17Al14, La66Ni19Al15, and La66Cu20Al14, exhibiting critical sizes for full glass formation of 16, 12, and 5 mm, respectively. Cobalt is found to be the most favorable element for glass formation in La-based alloys. The optimum alloys in La-TM-Al show close composition but significantly different glass-forming ability (GFA). The mechanism of distinct effect of TM elements remains unclear, even discussed based on current GFA-related criteria and indicators.

Controllable size of silicon (Si) nanocrystals can be achieved by a two-step rapid thermal annealing technique consisting of rapid annealing at 1000°C in nitrogen ambient and rapid oxidation at 600–800°C of a radio frequency magnetron co-sputtered Si-rich oxide/SiO2 superlattice structure. The photoluminescence (PL) spectra related to Si nanocrystals were observed in the visible range (600–900 nm). After rapid oxidation, the size of the nanocrystals was reduced and the quality of the Si nanocrystal/SiO2 interface was improved, resulting in a blue shift and an increase of the PL peak intensity. Finally, annealing in air increases the PL intensity further.

The aim of this study was to investigate long-term immunological changes after the treatment of Graves’ disease (GD) with thyroid arterial embolization and the effect of thyroid arterial embolization on the body’s immunological functions. Forty-one patients with clinically and laboratorily ascertained GD were treated with thyroid arterial embolization and followed up for 3–54 months following embolization. Prior to embolization and at 1, 3, 6, 12, and 36 months following embolization, thyroid autoimmune antibodies were tested respectively, including thyroid stimulating antibody (TSAb), thyrotropin antibody (TRAb), thyroglobulin antibody (TGAb), and thyroid microsomal antibody (TMAb), as well as subgroup lymphocytes of CD16+CD56+, CD19+, CD3+, CD3+CD4+ and CD3+CD8+. The autoimmune status of GD patients prior to embolization and the dynamic changes of the immunological function after embolization were analyzed. The therapy of thyroid arterial embolization could effectively decrease the activity/titer and positive rate of TRAb and the ratio of CD4+/ CD8+ to normal levels at 6 months following embolization, while the ratio of CD3+CD8+ increased gradually to normal level at 1 year following embolization. In patients with recurrence, TSAb and TRAb remained at a higher level, while the rate of CD3+CD8+ and the ratio of CD4+/CD8+ were not statistically significantly different from those before embolization. Immunological functional disorder exists in GD patients. The treatment method of thyroid arterial embolization can effectively resume the basic immunological function to normal range while patients with recurrence have no significant improvement, suggesting that thyroid arterial embolization has an effective role in adjusting the immunological function.

Atomically thin semiconducting transition-metal dichalcogenides have been attracting lots of attentions, particularly, molybdenum disulfide (MoS2) monolayers show promising applications in field effect transistors, optoelectronics and valleytronics. However, the controlled synthesis of highly crystalline MoS2 remain a challenge especially the systematic approach to manipulate its structure and morphology. Herein, we report a method for controlled synthesis of highly crystalline MoS2 by using chemical vapor deposition method with carbonaceous materials as growth promoter. A uniform and highly crystalline MoS2 monolayer with the grain size close to 40 μm was achieved. Furthermore, we extend the method to the manipulation of MoS2 morphology, flower-shape vertical grown MoS2 layers were obtained on growth promoting substrates. This simple approach allows an easy access of highly crystalline MoS2 layers with morphology tuned in a controllable manner. Moreover, the flower-shape MoS2 grown on graphene oxide film used as an anode material for lithium-ion batteries showed excellent electrochemical performance.

Atomically thin semiconducting transition-metal dichalcogenides have been attracting lots of attentions, particularly, molybdenum disulfide (MoS2) monolayers show promising applications in field effect transistors, optoelectronics and valleytronics. However, the controlled synthesis of highly crystalline MoS2 remain a challenge especially the systematic approach to manipulate its structure and morphology. Herein, we report a method for controlled synthesis of highly crystalline MoS2 by using chemical vapor deposition method with carbonaceous materials as growth promoter. A uniform and highly crystalline MoS2 monolayer with the grain size close to 40 μm was achieved. Furthermore, we extend the method to the manipulation of MoS2 morphology, flower-shape vertical grown MoS2 layers were obtained on growth promoting substrates. This simple approach allows an easy access of highly crystalline MoS2 layers with morphology tuned in a controllable manner. Moreover, the flower-shape MoS2 grown on graphene oxide film used as an anode material for lithium-ion batteries showed excellent electrochemical performance.

Development of technologies for water desalination and purification is critical to meet the global challenges of insufficient water supply and inadequate sanitation, especially for point-of-use applications. Conventional desalination methods are energy and operationally intensive, whereas adsorption-based techniques are simple and easy to use for point-of-use water purification, yet their capacity to remove salts is limited. Here we report that plasma-modified ultralong carbon nanotubes exhibit ultrahigh specific adsorption capacity for salt (exceeding 400% by weight) that is two orders of magnitude higher than that found in the current state-of-the-art activated carbon-based water treatment systems. We exploit this adsorption capacity in ultralong carbon nanotube-based membranes that can remove salt, as well as organic and metal contaminants. These ultralong carbon nanotube-based membranes may lead to next-generation rechargeable, point-of-use potable water purification appliances with superior desalination, disinfection and filtration properties.

Hybrid nanostructures composed of vertical graphene nanosheet (VGNS) and MoS2 nano-leaves are synthesized by the chemical vapor deposition method followed by a solvothermal process. The unique three-dimensional nanostructures of MoS2/VGNS arranged in a vertically aligned manner can be easily constructed on various substrates, including Ni foam and graphite paper. Compared with MoS2/carbon black, MoS2/VGNS nanocomposites grown on Ni foam exhibit enhanced electrochemical performance as the anode material of lithium-ion batteries, delivering a specific capacity of 1277 mAh g−1 at a current density of 100 mA g−1 and a high first-cycle coulombic efficiency of 76.6%. Moreover, the MoS2/VGNS nanostructures also retain a capacity of 1109 mAh g−1 after 100 cycles at a current density of 200 mA g−1, suggesting excellent cycling stability. In addition, when the MoS2/VGNS nanocomposites grown on graphite paper are applied in the hydrogen evolution reaction, a small Tafel slope of 41.3 mV dec−1 and a large double-layer capacitance of 7.96 mF cm−2 are obtained, which are among the best values achievable by MoS2-based hybrid structures. These results demonstrate the potential applications of MoS2/VGNS hybrid materials for energy conversion and storage and may open up a new avenue for the development of vertically aligned, multifunctional nanoarchitectures. Published version