Search

Sub-1-nanometer channels of membranes were orientedly induced by hydrophilic polysilsesquioxane nanocages, accomplishing ultrahigh proton-selective conductivity and surprisingly excellent durability in a flow battery.

Based on the time and location information of nodes, multi-sensor complex networks can achieve high-speed and low-delay exchange of control and sensor data between sensor nodes to ensure the accuracy and real-time performance of the entire detection and control system. However, complex multi-sensor networks face limitations in terms of computing, storage, and network resources. After grouping the sensor data of nodes, this paper employs an adaptive weighted data fusion method to complete the data fusion processing in the network. This approach can significantly reduce the data redundancy in the wireless sensor network, save a large amount of storage resources, and lower the network bandwidth occupation, with high efficiency and good scalability. The least square (LS) fitting is performed by two sets of temperature and humidity data obtained by weighted fusion at the cluster head node. Experimental results indicate that the fusion of two-dimensional data transmitted to the base station or control center can further diminish the amount of data transmission. In addition, after the adaptive weighted data fusion of the two-dimensional data at the cluster head node, the energy consumption of the cluster head node without the fusion and the cluster head node after the fusion is compared. The results demonstrate that the energy consumption of the cluster head node is notably abridged, the energy of the cluster head node is saved to a greater extent, and the life cycle of the network is prolonged.

The axially accelerating beam systems are widely used in engineering fields, which have abundant dynamical phenomena. In this work, we studied the periodic orbits and the phenomena of multistability of the system. The necessary and sufficient conditions for the existence of periodic orbits are derived by Schauder’s fixed point theorem and the averaging method. The theoretical results are in good agreement with the numerical analysis. Multistability is discussed in some set of parameter values. To predict the dynamical behaviors of the system in the long-term run, the effects of external excitation amplitude on the structures of basins of attraction are studied. The results reveal the influences of the physical parameters and initial values on the complex dynamical behaviors of the system, which can offer some guidance for selecting parameter values in engineering application of axially accelerating beams.

Achieving net-zero emissions requires low-cost and reliable energy storage devices that are essential to deploy renewables. Alkaline zinc-based flow batteries such as alkaline zinc-iron (or nickel) flow batteries are well-suited for energy storage because of their high safety, high efficiency, and low cost. Nevertheless, their energy density is limited by the low solubility of ferro/ferricyanide and the limited areal capacity of sintered nickel electrodes. Here, combining the electrochemical reaction with the chemical reaction of ferro/ferricyanide couple in a home-made nickel electrode, we report an alkaline zinc-iron/nickel hybrid flow battery with a high energy density of 208.9 Wh L

Poly(ether sulfone) (PES) is a kind of polymer materials with excellent electrical insulation and acid/alkali stability. PES can be operated at high temperature continuously for a long time and still maintain excellent property stability in the environments with rapidly changed temperature, namely, great thermostability. Moreover, PES has low molding shrinkage, good dimensional stability and excellent film-forming characteristics. Compared with inorganic membranes, PES-based membranes have lower cost, which have received more attention and wide recognition in the field of clean energy technologies in recent years, such as flow batteries, fuel cells, water treatment, and gas separation. Therefore, this review summarizes the research status and prospect of the utilization of PES-based membranes in clean energy fields, in order to further promote their development and application.

We present a coral-like FeP composite with FeP nanoparticles anchored and dispersed on a nitrogen-doped 3D carbon framework (FeP@NC). Due to the highly continuous N-doped carbon framework and a spring-buffering graphitized carbon layer around the FeP nanoparticle, a sodium-ion battery with the FeP@NC composite exhibits an ultra-stable cycling performance at 10 A g-1 with a capacity retention of 82.0 % in 10 000 cycles. Also, particle refinement leads to a capacity increase during cycling. The FeP nanoparticles go through a refining-recombination process during the first cycle and present a global refining trend after dozens of cycles, which results in a gradually increase in graphitization degree and interface magnetization, and further provides more active sites for Na+ storage and contributes to a rising capacity with cycling. The capacity ascending phenomenon can also extend to lithium-ion batteries.

The construction of chemical libraries containing polysubstituted pyrazoline scaffolds is highly desirable for the discovery of novel chemical ligands for biological targets. Herein, we report a sequential DNA-encoded synthesis strategy for polysubstituted pyrazoline heterocycles, which fuses a broad panel of aldehydes, aryl amines, and alkenes as building blocks. Furthermore, mock library synthesis and selection demonstrated the ability of the method to produce DNA-encoded focused libraries with highly functionalized pyrazoline cores.

Games have been one of the most popular applications on smartphones. In order to meet the increasing computational complexity of mobile games, smartphones are now equipped with heterogeneous CPU multi-core architectures like big.LITTLE as well as high-performance GPUs. However, the integrated CPUs and GPUs drain the battery quickly, which has become a bottleneck for improving user experience. In addition to traditional Dynamic Voltage and Frequency Scaling (DVFS) technique for CPUs and GPUs power reduction, heterogeneous multi-core processors, such as the big.LITTLE architecture, have been designed to offer more opportunity for performance-energy tradeoffs. But current processor governors in smartphones can not exploit these power-saving mechanisms wisely, causing considerable energy waste. In this article, we propose a CPU-GPU governing framework that recognizes the performance demand for different game scenes, and select the most energy-efficient hardware configuration for the corresponding scenes. We implement our framework on an ODROID-XU4 mobile platform, and the experiments show that our framework can achieve 26.7, 16.6, and 10.5 percent power saving on average without compromising user experience when compared to the default governor used in our platform and two governors proposed by other researchers, respectively.

In order to solve the problem of high energy consumption caused by node overload in complex network flow, a simulation load separation control algorithm based on complex network flow is proposed. According to the characteristics of complex network flow, combined with the characteristics of traffic in the network, a tree combined classifier is designed to discretize the complex network, analyze the micro dynamics of nodes in the network, and simulate the load division of nodes in complex network flow by dividing simulation load, evaluating node bandwidth, transferring overload nodes, and controlling the tree combined classifier. The experimental results show that the designed discrete control algorithm has the advantages of low cost, good load balancing, low energy consumption, and good simulation load discrete control performance.

The ever-increasing need for more energy-dense batteries is fuelling global research and innovations in new redox chemistry and device design. Lithium-ion batteries adopting organic electrolytes have the potential to deliver high energy densities, however, they usually have to compromise on safety‒a metric of equal importance. Here, we show an aqueous battery that exhibits a volumetric energy density far beyond the state of the art, together with long cycling life and excellent power performance. The high energy density is realized by employing highly concentrated hetero-halogen electrolytes that contain I- and Br-, which can realize a multi-electron transfer process of I-/IO3- with high reversibility and excellent kinetics. The intermediate bromide species can enhance the reaction kinetics and alleviate overpotential, leading to reversible and fast multi-electron transfer. Using a 6 M halogen electrolyte to achieve more than 30 M electron transfers per litre (the highest reported so far is 9 M), the I-/IO3- cathode displayed super high specific capacity of 830 Ah L-1. A battery with Cd/Cd2+ as anode demonstrated an energy density of >1200 Wh L-1catholyte, which is by far the highest value for aqueous batteries. Even at a current density of 120 mA cm-2 an energy efficiency of 72% can be obtained. Our work demonstrates that safe aqueous batteries with high energy density are possible, offering a new and evolutional option for grid scale energy storage and electric vehicles.

Mn

White-light emission (WLE) materials based on organic-inorganic hybrid lead halides have drawn considerable attention because of their applications in light-emission equipment. Despite considerable efforts, there is still a lack of two-dimensional (2D) lead-chlorine white-light emitting halides with high photoluminescence quantum efficiency (PLQE). Herein, we report the preparation of a new 2D layered hybrid halide, [DTHPE]Pb

Rechargeable aqueous zinc-based batteries (ZBBs) are attracting more and more attention for portable electronic equipment and large-scale energy storage due to their high energy density and low cos...

Layered vanadium oxides have been promising cathodes for rechargeable aqueous zinc ion batteries (AZIBs) owing to multiple valences of vanadium and relatively high interplanar spacing. However, it undergoes significant capacity decay due to vanadium dissolution and structural instability during cycling, especially at low current densities. Herein, PANI-intercalated V2O5 ((PANI)xV2O5, PAVO) hybrid bronzes with an ultra-high interlayer spacing of 13.9 A for use as an AZIB cathode have been reported. The inserted polyaniline not only acts as structural pillars because of the hydrogen bond between -NH2 group and V-O layer but also plays the role of ‘H+’ reservoir to prevent V-O matrix from H+ attacking. Accordingly, PAVO cathode delivers a specific capacity of 350 mAh g−1 with a capacity of ~90% over 100 cycles at a current density of 0.1 A g−1, which operates for about 1 month. This study unveils the dissolution mechanism of vanadium-based electrodes and improves the stability and electronic conductivity with organic molecule intercalation. Besides, the intercalation of guest molecule generates pros and cons (favorable higher interlayer, while adverse steric hindrance) to the Zn2+ diffusion and accordingly presents a different rate performance when compared to most of the previously reported work. Therefore, a new set of molecular-scale hybrid bronzes would be designed to achieve an optimized performance in the future.

Aqueous zinc-based batteries (ZBBs) have great potential as commercial energy storage devices. However, the poor cycling stability of zinc anode under high areal capacity limits their further application. Herein, a coupled non-planar electrode design achieved by the tailored flat-top pyramid carbon felt (TCF) is proposed for ZBBs, which can effectively increase the zinc deposition sites, adjust the deposition morphology, optimize the current and electrolyte flow velocity distribution and provide necessary space for zinc plating. Interestingly, by utilizing “tip effect”, the coupled TCFs enable precise control of the zinc dendrite growth position, effectively reducing the risk of short circuit. Based on such coupled TCFs, zinc-iodine flow batteries can deliver an ultra-high areal capacity of 240 mAh cm−2 and a superb cycling stability over 300 cycles (areal capacity of 160 mAh cm−2) at a high current density of 40 mA cm−2. Therefore, we provide an effective strategy for high areal capacity zinc anode design, which may promote the development of high energy density and long cycle life ZBBs.

A membrane with high stability and ion conductivity in wide pH range is essential for energy storage devices. Here, we report a novel membrane with hierarchical core–shell structure, which demonstrates high stability and ion conductivity, simultaneously under a wide pH range applications. Spectral characterizations and theoretical calculation indicate that the non-solvent induces the chain segment configuration and eventually leads to polymer–polymer phase separation, thus forming hierarchical porous core–shell structure. Benefiting from this structure, an acidic vanadium flow battery (VFB) with such a membrane shows excellent performance over 400 cycles with an energy efficiency (EE) of above 81% at current density of 120 mA cm−2 and an alkaline zinc-iron flow battery (AZIFB) delivers a cycling stability for more than 200 cycles at 160 mA cm−2, along with an EE of above 82%. This paper provides a cost-effective and simple way to fabricate membranes with high performance for variety of energy-related devices.

Lithium metal-based secondary batteries are very promising for next generation power battery due to their high energy density. However, lithium anodes suffer from poor electrochemical reversibility in organic electrolytes due to Li dendrites and instability of the solid electrolyte interphase. Recent research demonstrated that the problem can be alleviated via tetraethoxysilane (TEOS) treated lithium metal to form a silicon oxide layer on the lithium surface, however, its reaction mechanism is controversial. Herein, we deeply explore the reaction mechanism between TEOS and Li and propose: Fresh Li can directly react with TEOS even though no lithium hydroxide exists on the lithium surface, and the participation of water will accelerate the reaction process. Moreover, it was found that the silicon oxide layer can promote the uniform deposition of lithium ions by providing lithiophilic nucleation sites, thereby achieving a long cycle life of Li metal batteries.

Nitrocellulose (NC) is proposed to stabilize the electrolytes for Li metal batteries. The nitro group of NC preferentially reacts with Li metal, and along with the cellulose skeleton is tightly wrapped on the surface, so that the polymer-inorganic double layer is formed on the Li surface. XPS profile analysis and corroborative cryo-environmental TEM reveal that the flexible outer layer of the bilayer is a C-O organic layer, while the dense inner layer is mainly composed of crystalline lithium oxide, lithium oxynitride, and lithium nitride. The Li deposition process was observed via in situ optical microscopy, which indicated that the NC-derived bilayer facilitates the uniform deposition of Li ions and inhibits the growth of dendrites. After the introduction of NC into the electrolyte, the cycle life of the Li battery is twice than that of the Li battery without NC at 1.0 and 3.0 mA cm-2 .

A high power density vanadium flow battery (VFB) is essential for reducing the cost of a VFB system. The power density of a VFB is currently limited by the negative half-cell since the negative V2+...

Alkaline zinc-based batteries are becoming promising candidates for green and economical energy-storage systems, thanks to their low cost and high energy density. The exploitation of the stable cathode materials with high rate capability and cycling stability is crucial for their further development. Herein, a series of NiSx coated with nitrogen-doped carbon (denoted as NiSx@NC) compounds (x = 0.5-1.0) are synthesized using the facile single-source precursor method. Benefiting from the unique phase-transitional NiSx@NC with high activity and enhanced conductivity from the well-balanced conductive metal nickel and carbon layer, the alkaline zinc-nickel batteries with a phase-transitional NiSx@NC cathode deliver a high capacity of 148 mA h g-1 at a high current density of 100 mA cm-2 and demonstrate a long lifespan of over 500 cycles with a high capacity retention of 98.8%. This work provides a significant guideline for the structural design and optimization of nickel-based materials in alkaline energy-storage devices.

Reducing carbon dioxide to high value-added chemicals is of high importance due to its vital role in mitigating CO2 emission and energy crisis. However, seeking for robust catalysts with low overpo...

Sodium ion batteries (SIBs) have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources. However, they face serious challenges of low energy & power density and short cycling lifespan owing to the heavy mass and large radius of Na+. Vanadium-based polyanionic compounds have advantageous characteristic of high operating voltage, high ionic conductivity and robust structural framework, which is conducive to their high energy & power density and long lifespan for SIBs. In this review, we will overview the latest V-based polyanionic compounds, along with the respective characteristic from the intrinsic crystal structure to performance presentation and improvement for SIBs. One of the most important aspect is to discover the essential problems existed in the present V-based polyanionic compounds for high-energy & power applications, and point out most suitable solutions from the crystal structure modulation, interface tailoring and electrode configuration design. Moreover, some scientific issues of V-based polyanionic compounds shall be also proposed and related future direction shall be provided. We believe that this review can serve as a motivation for further development of novel V-based polyanionic compounds and drive them toward high energy & power applications in the near future.

Aqueous redox flow batteries (ARFBs) are regarded as promising candidates for large-scale energy storage. In particular, ARFBs based on organic redox-active species can largely reduce the capital cost and mineral resource requirements. However, the design of redox-active organic materials with desirable electrochemical performances needs to be further explored. Herein, we report a green and low-cost synthesis of a highly soluble N-alkyl-carboxylate-functionalized derivative of 2,6-diaminoanthraquinone, namely, N,N'-(9,10-anthraquinone-2,6-diyl)-di-β-alanine (DAEAQ), which exhibits a high voltage plateau and long cycling life when serving as an anolyte in ARFBs. The alkaline ARFBs based on DAEAQ anolyte and potassium ferrocyanide (K4Fe(CN)6) catholyte deliver a high open-circuit voltage of 1.12 V at pH ≥12. When sandwiched with a custom highly-sulfonated and nonfluorinated cation exchange membrane, the as-prepared ARFBs achieve an excellent maximum power density of 0.34 W cm−2 and an optimal capacity retention rate of 99.86% day−1. This work highlights the great potential of rationally designed anthraquinone derivatives in ARFBs for grid-scale renewable and sustainable energy storage applications.