Magnesium has been regarded as an intriguing anode material for chloride ion batteries (CIB) because of its abundant resources, multi-electron reaction feature, and high volumetric capacity. However, ...the passivation of magnesium in the electrolyte and formation of insulating MgCl
2
discharge product lead to poor reaction activity of magnesium anode in CIBs. Herein, the Mg
2
Sn alloy prepared by mechanical alloying of magnesium and tin powders is first developed as the anode material with enhanced interfacial activity in the CIB using a metal chloride cathode. The cathode exhibits a significant increase in the discharge capacity from 82 to 175 mAh g
−1
when an Mg/carbon anode was replaced by the Mg
2
Sn alloy anode. The discharge capacity can be further increased to more than 200 mAh g
−1
when the graphene nanoplatelet is incorporated in the Mg
2
Sn alloy by mechanical milling, thus demonstrating the highly active alloy anode for chloride ion storage. This strategy also benefits the improvement in the cycling performance of the magnesium anode.
Solid electrolytes have attracted considerable interest in rechargeable batteries because of their potential high safety, inhibition of electrode dissolution, and large electrochemical window. ...However, their development in some new battery concepts such as room-temperature halide ion batteries has been scarce. Herein, we develop the inorganic halide perovskite of CsSnCl3 prepared by mechanical milling and subsequent mild heat treatment as the potential solid electrolyte for chloride ion batteries (CIB). Benefiting from its high structural stability against a phase transformation to monoclinic structure at room temperature, the as-prepared cubic CsSnCl3 achieves an impressive electrochemical performance with the highest ionic conductivity of 3.6 × 10–4 S cm–1 and a large electrochemical window of about 6.1 V at 298 K. These values are much higher than 1.2 × 10–5 S cm–1 and 4.25 V of the previously reported solid polymer electrolyte for CIBs. Importantly, the chloride ion transfer of the as-prepared CsSnCl3 electrolyte is demonstrated by employing the electrode couples of SnCl2/Sn and BiCl3/Bi.
Organic molecules such as viologens with a nitrogen redox center show promise as efficient anion storage materials in rechargeable batteries. However, the high solubility of viologens in liquid ...electrolytes limits their wide electrochemical application. Herein, an insoluble polymerized polyxylylviologen chloride (PXVCl2) is first developed as a chloride ion storage electrode in chloride ion batteries. The as-prepared PXVCl2 electrode exhibits a competitive discharge capacity of 140 mA h g–1 (86% of the theoretical discharge capacity) compared to that of the previously reported organic conducting polymer electrodes. The incorporation of graphene in the PXVCl2 material achieves significant improvements in reaction reversibility and rate capability of the PXVCl2 electrode. Importantly, the nitrogen redox reactions based on chloride ion transfer of the PXVCl2 electrode are demonstrated.
Perovskite chloride, an anion conductor, is a promising candidate to be a solid electrolyte for high‐energy and sustainable chloride ion batteries (CIB). However, it suffers from poor structural ...stability at low temperature and in ambient conditions, which leads to its transformation from an ionic conductor to an insulator. Herein, a bismuth and chlorine dual doping strategy is developed to stabilize the cubic structure of CsSnCl3 in harsh environments. The as‐prepared dual‐doped CsSn0.9Bi0.1Cl3.1 material with an optimized composition maintains its cubic structure at the extremely low temperature of 213 K for 10 days and at 40% relative humidity for 50 days, while the undoped cubic material deteriorates and transforms to a monoclinic phase under these conditions in less than 1 day. Consequently, the dual doping achieves efficient chloride ion conduction that is superior to single bismuth doping due to the introduction of interstitial chlorine facilitating chloride ion transport. Importantly, the practicality of the as‐prepared solid electrolyte is demonstrated in different symmetric solid cells and by various CIBs using the organic electrode couple, a multivalent metal chloride cathode, or a new high‐voltage metal oxychloride cathode.
A bismuth and chlorine dual doping approach is developed to stabilize the cubic structure of perovskite chloride against the extremely low temperature of 213 K and ambient conditions with 40% relative humidity for a long period, thereby yielding the cubic CsSn0.9Bi0.1Cl3.1 solid electrolyte with efficient chloride ion conduction in different symmetric solid cells and various rechargeable chloride ion batteries.
Iron oxide (Fe2O3) is an intriguing anode material of electrochemical energy storage systems such as rechargeable batteries. The rational design of its nanostructure at mild condition to cope with ...the issues of low reversible capacity and sluggish kinetics is required. Herein, an efficient, facile, and potentially large-scale synthesis approach using the precursor of laminated iron oxychloride@polyaniline heterostructure and mild annealing is developed, yielding unique Fe2O3@carbon nanocomposites with hematite nanoparticles (∼20 nm) that embedded in nitrogen/chlorine-doped carbon nanodisk (N/Cl–C). Given the benefit of abundant active sites, good chemical contact between carbon and Fe2O3, and robust composite structure, the as-prepared Fe2O3@N/Cl–C anode material delivers competent lithium-ion storage properties, including high reversible capacity of 1010 mAh g−1 (based on the mass of the as-prepared nanocomposite) at 0.1 A g−1, decent rate performance upon a rigorous current change, and superior cycling stability with 955 mAh g−1 after 180 cycles as well as a sustained Coulombic efficiency of about 99%. This structural design may provide a new avenue for achieving efficient iron oxide-based materials in chemical and electrochemical applications such as catalysis, lithium-ion batteries, and sodium-ion batteries.
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•Developing a novel, facile and scalable synthesis approach for hematite/carbon nanocomposites.•N/Cl-doped carbon nanodisk-encapsulated hematite anode shows robust structure for Li-ion storage.•High reversible capacity, decent rate capability and superior cycling performance are achieved.
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•The polyaniline/graphene material is first employed as the faradaic electrode in the desalination system.•The as-prepared polyaniline-based electrode delivers a high reversible ...capacity of 126 mA h g−1.•Competitive chloride ion storage performance of the polyaniline electrode is achieved.
The use of anion storage materials has played an important role in the development of electrochemical energy storage systems and water desalination. Herein, the graphene-supported polyaniline (PANI/GN) nanomaterial is developed as a new chloride ion storage electrode in aqueous sodium chloride solution. The as-prepared PANI/GN electrode exhibits highly reversible electrochemical stability in both a three-electrode system and a full desalination battery using a sodium ion storage electrode. Competitive electrochemical properties with a reversible capacity of 126 mA h g−1, a coulombic efficiency of more than 95 % and a high rate capability are achieved for the PANI/GN electrode compared to the previously reported electrodes of metals, antimony oxychloride, and polypyrrole. The anionic chloride species instead of covalent chloride species in the as-prepared PANI/GN is demonstrated to be electrochemically active.
Single image matting, the task of estimating accurate foreground opacity from a given image, is a severely ill-posed and challenging problem. Inspired by recent advances in image co-segmentation, in ...this paper, we present a novel framework for a new task called co-matting, which aims to simultaneously extract alpha mattes in multiple images that contain slightly deformed instances of the same foreground object against different backgrounds. Our system first generates trimaps for input images using co-segmentation, and an initial alpha matte for each image using single image matting. Each alpha matte is then locally evaluated using a novel matting confidence metric learned from a training dataset. In the co-matting step, we first align the foreground object instances using appearance and geometric features, then apply a global optimization on all input images to jointly improve their alpha mattes, which allows high confidence local regions to guide their corresponding low confidence ones in other images to achieve more accurate mattes all together. Experimental results show that this co-matting framework can achieve noticeably higher quality results on an image stack than applying state-of-the-art single image matting techniques individually on each image.
Overview of our system. Given two input images and their corresponding trimaps (indicated by green lines) in (a), we first generate an initial matte for each image in (b) using single image matting. Region-wise matting confidence shown in (c) is evaluated for each initial matte, and inter-image unknown region registration shown in (d) is established. All the information is then incorporated in a global optimization procedure to derive refined mattes of both images shown in (e). Display omitted
•We present a novel framework for a new task called co-matting.•Co-matting extracts alpha mattes in images with deformed foreground against backgrounds.•We apply optimization to jointly improve the alpha mattes extracted from aligned foreground.•Each alpha matte is evaluated using a matting confidence metric learned from a training dataset.•Experiments show that the framework achieves noticeably higher quality results on an image stack.
We propose a new method to detect deepfake images using the cue of the source feature inconsistency within the forged images. It is based on the hypothesis that images' distinct source features can ...be preserved and extracted after going through state-of-the-art deepfake generation processes. We introduce a novel representation learning approach, called pair-wise self-consistency learning (PCL), for training ConvNets to extract these source features and detect deepfake images. It is accompanied by a new image synthesis approach, called inconsistency image genera-tor (I2G), to provide richly annotated training data for PCL. Experimental results on seven popular datasets show that our models improve averaged AUC over the state of the art from 96.45% to 98.05% in the in-dataset evaluation and from 86.03% to 92.18% in the cross-dataset evaluation.
TiO2/ZnO nanowire arrays on stainless steel mesh for piezo-photocatalytic H2 production are synthesized via a two-step hydrothermal route. The photocatalytic H2 production efficiency under solar ...illumination can be enhanced by introducing mechanical vibration energy. As coutilizing the solar and mechanical energy (ultrasonic irradiation), the nanowires show high H2 production. The nanowire arrays also show excellent recyclability and stability. Additionally, this mesh-based structure can be retrieved easily from aqueous solution, which can meet the practical application demand. The working mechanism can be attributed to the piezo-photocatalytic effect, in which the piezoelectric field of bent ZnO nanowires and the built-in electric field of TiO2/ZnO heterostructures can efficiently separate the photogenerated electrons and holes for effectively producing H2. Present results provide a new strategy for developing photocatalytic H2 production techniques.
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