Owing to their significant physiological functions, especially as selective relays for translocation of physiological relevant species through cellular membranes, natural ion channels play important ...role in the living organisms. During the last decades, the field of self‐assembled ion channels has been continuously developed. Convergent multidimensional self‐assembly strategies have been used for the synthesis of unimolecular channels or non‐covalent self‐organized channels, designed to mimic natural ion channel proteins and for which a rich array of interconverting or adaptive channel conductance states can be observed. In this review, we give an overview on the development of various self‐assembled artificial channels in a bottom‐up approach, especially their design, self‐assembly behaviour, transport activity in lipid bilayer membranes, mechanism of transport and comparison with natural ion channels. Finally, we discuss their applications, the potential challenges facing in this field as well as future development and perspectives.
This Review gives an overview of the various types of supramolecular self‐assembled artificial ion‐channels: capsules and cages, macrocyclic stacks, tubular helical architectures.
High‐energy‐density Li metal batteries suffer from a short lifespan under practical conditions, such as limited lithium, high loading cathode, and lean electrolytes, owing to the absence of ...appropriate solid electrolyte interphase (SEI). Herein, a sustainable SEI was designed rationally by combining fluorinated co‐solvents with sustained‐release additives for practical challenges. The intrinsic uniformity of SEI and the constant supplements of building blocks of SEI jointly afford to sustainable SEI. Specific spatial distributions and abundant heterogeneous grain boundaries of LiF, LiNxOy, and Li2O effectively regulate uniformity of Li deposition. In a Li metal battery with an ultrathin Li anode (33 μm), a high‐loading LiNi0.5Co0.2Mn0.3O2 cathode (4.4 mAh cm−2), and lean electrolytes (6.1 g Ah−1), 83 % of initial capacity retains after 150 cycles. A pouch cell (3.5 Ah) demonstrated a specific energy of 340 Wh kg−1 for 60 cycles with lean electrolytes (2.3 g Ah−1).
A solid electrolyte interphase (SEI) was proposed for practical high‐energy‐density Li batteries. The intrinsic uniformity and the constant supplements of building blocks of SEI jointly afford a sustainable SEI. A pouch cell with a specific energy of 340 Wh kg−1 underwent 60 cycles with a retention of 90 %.
The paper proposes a cooperative scheme for the coexistence of a multiple-input-multiple-output (MIMO) communication system and a matrix completion (MC) based, collocated MIMO (MIMO-MC) radar. To ...facilitate the coexistence, and also deal with clutter, both the radar and the communication systems use transmit precoding. For waveform flexibility, the radar uses a random unitary waveform matrix. We prove that for such waveforms and any precoding matrix, the error performance of MC is guaranteed. The radar transmit precoder, the radar subsampling scheme, and the communication transmit covariance matrix are jointly designed in order to maximize the radar SINR, while meeting certain communication rate and power constraints. The joint design is implemented at a control center, which is a node with whom both systems share physical layer information, and which also performs data fusion for the radar. We provide efficient algorithms for the proposed optimization problem, along with insight on the feasibility and properties of the proposed design. Simulation results show that the proposed scheme significantly improves the spectrum sharing performance in various scenarios.
Dilute alloying is an effective strategy to tune properties of solid catalysts but is rarely leveraged in complex reactions beyond small molecule conversion. In this work, dilute dopants are ...demonstrated to serve as activating centers to construct multiatom catalytic domains in metal nitride electrocatalysts for lithium–sulfur (Li–S) batteries, of which the sulfur cathode suffers from sluggish and complex conversion reactions. With titanium nitride (TiN) as a model system, the dilute cobalt alloying is shown to greatly improve the reaction kinetics while inducing negligible catalyst reconstruction. Compared to the pristine TiN, the dilute nitride alloy catalyst enables onefold increase in the high rate (2.0 C) capacities of Li–S batteries, as well as an impressively low cyclic decay rate of 0.17% at a sulfur loading of 4.0 mgS cm−2. This work opens up new opportunities toward the rational design of Li–S electrocatalysts by dilute alloying and also enlightens the understandings of complex domain‐catalyzed reactions in energy applications.
Dilute alloying implants “activating” centers in nitride alloy electrocatalysts to boost lithium–sulfur (Li–S) batteries. Dilute Co dopants activate the surrounding N and Ti atoms to construct multiatom active domains for efficient bidirectional catalysis of S redox reactions. The corresponding dilute nitride alloy improves the reaction kinetics and electrochemical performance of Li–S batteries.
Stable operation at elevated temperature is necessary for lithium metal anode. However, Li metal anode generally has poor performance and safety concerns at high temperature (>55 °C) owing to the ...thermal instability of the electrolyte and solid electrolyte interphase in a routine liquid electrolyte. Herein a Li metal anode working at an elevated temperature (90 °C) is demonstrated in a thermotolerant electrolyte. In a Li|LiFePO4 battery working at 90 °C, the anode undergoes 100 cycles compared with 10 cycles in a practical carbonate electrolyte. During the formation of the solid electrolyte interphase, independent and incomplete decomposition of Li salts and solvents aggravate. Some unstable intermediates emerge at 90 °C, degenerating the uniformity of Li deposition. This work not only demonstrates a working Li metal anode at 90 °C, but also provides fundamental understanding of solid electrolyte interphase and Li deposition at elevated temperature for rechargeable batteries.
A Li metal anode working at 90 °C is demonstrated in a thermotolerant liquid electrolyte. The anode undergoes 100 cycles in a Li|LiFePO4 battery at 90 °C (10 cycles in a practical carbonate electrolyte). High operation temperature promotes independent and incomplete decomposition of Li salts and solvents to form a distinctive solid electrolyte interphase.
Although biomimetic designs are expected to play a key role in exploring future structural materials, facile fabrication of bulk biomimetic materials under ambient conditions remains a major ...challenge. Here, we describe a mesoscale "assembly-and-mineralization" approach inspired by the natural process in mollusks to fabricate bulk synthetic nacre that highly resembles both the chemical composition and the hierarchical structure of natural nacre. The millimeter-thick synthetic nacre consists of alternating organic layers and aragonite platelet layers (91 weight percent) and exhibits good ultimate strength and fracture toughness. This predesigned matrix-directed mineralization method represents a rational strategy for the preparation of robust composite materials with hierarchically ordered structures, where various constituents are adaptable, including brittle and heat-labile materials.
Safe and rechargeable lithium metal batteries have been difficult to achieve because of the formation of lithium dendrites. Herein an emerging electrolyte based on a simple solvation strategy is ...proposed for highly stable lithium metal anodes in both coin and pouch cells. Fluoroethylene carbonate (FEC) and lithium nitrate (LiNO3) were concurrently introduced into an electrolyte, thus altering the solvation sheath of lithium ions, and forming a uniform solid electrolyte interphase (SEI), with an abundance of LiF and LiNxOy on a working lithium metal anode with dendrite‐free lithium deposition. Ultrahigh Coulombic efficiency (99.96 %) and long lifespans (1000 cycles) were achieved when the FEC/LiNO3 electrolyte was applied in working batteries. The solvation chemistry of electrolyte was further explored by molecular dynamics simulations and first‐principles calculations. This work provides insight into understanding the critical role of the solvation of lithium ions in forming the SEI and delivering an effective route to optimize electrolytes for safe lithium metal batteries.
Not dead ′Li′: Fluoroethylene carbonate (FEC) and lithium nitrate (LiNO3) were concurrently introduced into an electrolyte, thus altering the solvation sheath of lithium ions and forming a uniform solid electrolyte interphase (SEI). An abundance of LiF and LiNxOy is formed on the working lithium metal anode and contributes to dendrite‐free lithium deposition.
The electrode/electrolyte interface plays a critical role in stabilizing the cycling performance and prolonging the service life of rechargeable batteries to meet the sustainable energy requirements ...of the mobile society. The understanding of interfaces is still at the preliminary stage due to the limited research techniques and variable properties with time and potential. Herein, the latest developments focused on the interfaces in rechargeable systems including the cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) are reviewed. The possible formation mechanisms of the electrode/electrolyte interface are discussed, followed by the introduction of two key influencing factors, specific adsorption and solvated coordinate structure, which will dominate the formation of the interface. Finally, the structure and chemical composition of the interface as well as the possible transport mechanism of lithium ions in the interface and the strategies to regulate the pathway through the interface are presented in detail. This work sheds light on the fundamental understanding of the interface and provides rational scientific principles in designing the electrode/electrolyte interface and inspires the rational design of long‐term cycling rechargeable batteries.
The electrode/electrolyte interface plays a critical role in stabilizing the cycling performance and prolonging the service life of rechargeable batteries. This work discusses the formation mechanism of the interface and summarizes the progress in the structure/composition modulation of the interface toward advanced battery systems.
LiDAR-based or RGB-D-based object detection is used in numerous applications, ranging from autonomous driving to robot vision. Voxel-based 3D convolutional networks have been used for some time to ...enhance the retention of information when processing point cloud LiDAR data. However, problems remain, including a slow inference speed and low orientation estimation performance. We therefore investigate an improved sparse convolution method for such networks, which significantly increases the speed of both training and inference. We also introduce a new form of angle loss regression to improve the orientation estimation performance and a new data augmentation approach that can enhance the convergence speed and performance. The proposed network produces state-of-the-art results on the KITTI 3D object detection benchmarks while maintaining a fast inference speed.
Lithium–sulfur (Li–S) batteries hold great promise to serve as next‐generation energy storage devices. However, the practical performances of Li–S batteries are severely limited by the sulfur cathode ...regarding its low conductivity, huge volume change, and the polysulfide shuttle effect. The first two issues have been well addressed by introducing mesoporous carbon hosts to the sulfur cathode. Unfortunately, the nonpolar nature of carbon materials renders poor affinity to polar polysulfides, leaving the shuttling issue unaddressed. In this contribution, atomic cobalt is implanted within the skeleton of mesoporous carbon via a supramolecular self‐templating strategy, which simultaneously improves the interaction with polysulfides and maintains the mesoporous structure. Moreover, the atomic cobalt dopants serve as active sites to improve the kinetics of the sulfur redox reactions. With the atomic‐cobalt‐decorated mesoporous carbon host, a high capacity of 1130 mAh gS−1 at 0.5 C and a high stability with a retention of 74.1% after 300 cycles are realized. Implanting atomic metal in mesoporous carbon demonstrates a feasible strategy to endow nanomaterials with targeted functions for Li–S batteries and broad applications.
Atomic cobalt implantation to mesoporous carbon enhances the sulfur kinetics in Li–S batteries. Atomic cobalt dopants with high polarity endow the mesoporous carbon (represented by the apes) with high affinity with polysulfides (represented by the bananas). Therefore, the shuttle effect is eliminated and the sulfur kinetics is improved, facilitating highly stable Li–S batteries.
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