Changsha University

Commercial lithium-ion (Li-ion) batteries suffer from low energy density and do not meet the growing demands of the energy storage market. Therefore, building next-generation rechargeable Li and Li-ion batteries with higher energy densities, better safety characteristics, lower cost and longer cycle life is of outmost importance. To achieve smaller and lighter next-generation rechargeable Li and Li-ion batteries that can outperform commercial Li-ion batteries, several new energy storage chemistries are being extensively studied. In this review, we summarize the current trends and provide guidelines towards achieving this goal, by addressing batteries using high-voltage cathodes, metal fluoride electrodes, chalcogen electrodes, Li metal anodes, high-capacity anodes as well as useful electrolyte solutions. We discuss the choice of active materials, practically achievable energy densities and challenges faced by the respective battery systems. Furthermore, strategies to overcome remaining challenges for achieving energy characteristics are addressed in the hope of providing a useful and balanced assessment of current status and perspectives of rechargeable Li and Li-ion batteries.

We report a new class of Zn anodes modified by a three-dimensional nanoporous ZnO architecture (Zn@ZnO-3D), which can accelerate the kinetics of Zn²⁺ transfer and deposition, inhibit dendrite growth, and reduce the side-reactions.

conversion and degradation of environmental contaminants. Finally, a summary and perspective on the opportunities and challenges for the future development of COF and COF-based photocatalysts are given.

We report the chemical intercalation of Li⁺ into the interlayer of V₂O₅·<italic>n</italic>H₂O with enlarged layer spacing and fast Zn²⁺ diffusion, resulting in high rate capability and excellent long-term cycling performance.

A direct Z-scheme g-C₃N₄/ZnO binary composite photocatalytic system was constructed and exhibited enhanced photocatalytic CO₂ reduction activity compared to g-C₃N₄ or ZnO.

The fundamentals and perspectives in developing zinc-ion electrolyte have been comprehensively revealed, include the basic characteristics, electrolyte/electrode interfaces, practical consideration and future perspectives.

Recent years have witnessed an upsurge in the development of non-precious catalysts (NPCs) for alkaline water electrolysis (AWE), especially with the strides made in experimental and computational techniques. In this contribution, the most recent advances in NPCs for AWE were systematically reviewed, emphasizing the application of in situ/operando experimental methods and density functional theory (DFT) calculations in their understanding and development. First, we briefly introduced the fundamentals of the anode and cathode reaction for AWE, i.e., the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), respectively. Next, the most popular in situ/operando approaches for characterizing AWE catalysts, including hard and soft XAS, ambient-pressure XPS, liquid and identical location TEM, electrochemical mass spectrometry, and Raman spectroscopy were thoroughly summarized. Subsequently, we carefully discussed the principles, computational methods, applications, and combinations of DFT with machine learning for modeling NPCs and predicting the alkaline OER and HER. With the improved understanding of the structure-property-performance relationship of NPCs for AWE, we proceeded to overview their current development, summarising state-of-the-art design strategies to boost their activity. In addition, advances in various extensively investigated NPCs for AWE were evaluated. By conveying these methods, progress, insights, and perspectives, this review will contribute to a better understanding and rational development of non-precious AWE electrocatalysts for hydrogen production.

As a newly emerging class of porous materials, covalent organic frameworks (COFs) have attracted much attention due to their intriguing structural merits (e.g., total organic backbone, tunable porosity and predictable structure). However, the insoluble and unprocessable features of bulk COF powder limit their applications. To overcome these limitations, considerable efforts have been devoted to exploring the fabrication of COF thin films with controllable architectures, which open the door for their novel applications. In this critical review, we aim to provide the recent advances in the fabrication of COF thin films not only supported on substrates but also as free-standing nanosheets via both bottom-up and top-down strategies. The bottom-up strategy involves solvothermal synthesis, interfacial polymerization, room temperature vapor-assisted conversion, and synthesis under continuous flow conditions; whereas, the top-down strategy involves solvent-assisted exfoliation, self-exfoliation, mechanical delamination, and chemical exfoliation. In addition, the applications of COF thin films including energy storage, semiconductor devices, membrane-separation, sensors, and drug delivery are summarized. Finally, to accelerate further research, a personal perspective covering their synthetic strategies, mechanisms and applications is presented.

Single-layer chromium trihalides constitute a series of stable 2D intrinsic FM half semiconductors with large magnetic anisotropy energies.

Electrocatalysis plays an essential role in diverse electrochemical energy conversion processes that are vital for improving energy utilization efficiency and mitigating the aggravating global warming challenge. The noble metals such as platinum are generally the most frequently used electrocatalysts to drive these reactions and facilitate the relevant energy conversion processes. The high cost and scarcity of these materials pose a serious challenge for the wide-spread adoption and the sustainability of these technologies in the long run, which have motivated considerable efforts in searching for alternative electrocatalysts with reduced loading of precious metals or based entirely on earth-abundant metals. Of particular interest are graphene-supported single atom catalysts (G-SACs) that integrate the merits of heterogeneous catalysts and homogeneous catalysts, such as high activity, selectivity, stability, maximized atom utilization efficiency and easy separation from reactants/products. The graphene support features a large surface area, high conductivity and excellent (electro)-chemical stability, making it a highly attractive substrate for supporting single atom electrocatalysts for various electrochemical energy conversion processes. In this review, we highlight the recent advancements in G-SACs for electrochemical energy conversion, from the synthetic strategies and identification of the atomistic structure to electrocatalytic applications in a variety of reactions, and finally conclude with a brief prospect on future challenges and opportunities.

Abstract Graphite as an anode for the potassium ion battery (PIBs) has the merits of low cost and potentially high energy density, while suffering from limited cycle time and inferior stability. Herein we, using a concentrated electrolyte, demonstrate that formation of a robust inorganic‐rich passivation layer on the graphite anode could resolve these problems. Consequently, the PIBs with graphite anode could operate for over 2000 cycles (running time of over 17 months) with negligible capacity decay, and had a high area capacity over 7.36 mAh cm −2 with a high mass loading of 28.56 mg cm −2 . These unprecedented performances of graphite are comparable to that of traditional lithium‐ion batteries, and may promote the rapidly development of high performance PIBs.

Abst rac t- Flooding in mobile ad hoc networks has poor scalability as it leads to serious redundancy, contention and collision. In this paper, we propose an efficient approach to reduce the broadcast redundancy. In our approach, local topology information and the statistical information about the duplicate broadcasts are utilized to avoid unnecessary rebroadcasts. Simulation is conducted to compare the performance of our approach and flooding. The simulation results demonstrate the advantages of our approach. It can greatly reduce the redundant messages, thus saving much network bandwidth and energy. It can also enhance the reliability of broadcasting. It can be used in static or mobile wireless networks to implement scalable broadcast or multicast communications. I.

This review highlights the recent developments of cathode materials for aqueous zinc-ion batteries, which are cost effective and have good safety.

A multiphasic 1T/2H MoS₂ electrocatalyst for hydrogen evolution, which exhibits excellent performances with a small Tafel slope of 46 mV dec⁻¹, is developed by phase engineering <italic>via</italic> a simple hydrothermal route.

Nanoscale Bi-based photocatalysts are promising candidates for visible-light-driven photocatalytic environmental remediation and energy conversion. However, the performance of bulk bismuthal semiconductors is unsatisfactory. Increasing efforts have been focused on enhancing the performance of this photocatalyst family. Many studies have reported on component adjustment, morphology control, heterojunction construction, and surface modification. Herein, recent topics in these fields, including doping, changing stoichiometry, solid solutions, ultrathin nanosheets, hierarchical and hollow architectures, conventional heterojunctions, direct Z-scheme junctions, and surface modification of conductive materials and semiconductors, are reviewed. The progress in the enhancement mechanism involving light absorption, band structure tailoring, and separation and utilization of excited carriers, is also introduced. The challenges and tendencies in the studies of nanoscale Bi-based photocatalysts are discussed and summarized.

Two-dimensional semiconductors (2DSCs) have attracted considerable attention as atomically thin channel materials for field-effect transistors. Each layer in 2DSCs consists of a single- or few-atom-thick, covalently bonded lattice, in which all carriers are confined in their atomically thin channel with superior gate controllability and greatly suppressed OFF-state current, in contrast to typical bulk semiconductors plagued by short channel effects and heat generation from static power. Additionally, 2DSCs are free of surface dangling bonds that plague traditional semiconductors, and hence exhibit excellent electronic properties at the limit of single atom thickness. Therefore, 2DSCs can offer significant potential for the ultimate transistor scaling to single atomic body thickness. Earlier studies of graphene transistors have been limited by the zero bandgap and low ON-OFF ratio of graphene, and transition metal dichalcogenide (TMDC) devices are typically plagued by insufficient carrier mobility. To this end, considerable efforts have been devoted towards searching for new 2DSCs with optimum electronic properties. Within a relatively short period of time, a large number of 2DSCs have been demonstrated to exhibit unprecedented characteristics or unique functionalities. Here we review the recent efforts and progress in exploring novel 2DSCs beyond graphene and TMDCs for ultra-thin body transistors, discussing the merits, limits and prospects of each material.

Since ever-increasing energy demands stimulated intensive research activities on lithium-ion batteries (LIBs), biomass as an earth-abundant renewable energy source has played an intriguing and promising role in developing sustainable biomass-derived carbons and their composite materials for high-performance LIB anodes. Different from other materials (e.g., silicon, tin, metal oxides, etc.), biomass-derived carbons and their composite materials have been applied more and more to LIBs due to their advantages such as low cost, green and eco-friendly synthesis, easy accessibility, sustainable strategy, and improved battery performance, including capacity, cycling property, and stability/durability. This tutorial review focusing on biomass-derived carbons and their composites in the application of LIB anodes will act as a strategic guide to build a close connection between renewable materials and electrochemical energy storage devices. Also, this review provides a critical analysis and comparison of biomass-derived carbons and their composites for LIB anodes, coupled with an important insight into the remaining challenges and future directions in the field.

Rechargeable aqueous zinc ion batteries (ZIBs) are highly desirable for large-scale energy storage due to their advantages of safety and low-cost. Development of advanced cathodes for use in aqueous ZIBs is urgently needed. Herein, we report a low-cost rechargeable aqueous Zn-V2O5 cell with 3 M ZnSO4 electrolyte that demonstrates high zinc storage capability. We also investigated the effect of different types/concentrations of the aqueous electrolytes on the performance of the Zn-V2O5 cells.

This review provides a comprehensive overview of amidoxime-based materials for uranium recovery and removal from the perspectives of synthesis, characterizations, types, influence factors, binding mechanisms, and cost evaluation.

We report a series of ammonium vanadates as cathodes for aqueous ZIBs and provide insights into the origin of the enhanced electrochemical behaviors. The NH₄V₄O₁₀ compound, with the largest interplanar spacing (9.8 Å), exhibits excellent electrochemical performance.