Entropy-Assisted Doping Strategy Enabling Chemo-Mechanically Reliable Ultrahigh-Ni Co-Free Polycrystalline Cathode for Commercializable Lithium-Ion Batteries.

Recently, Co-free Ni-rich cathodes have received extensive concerns as a competitive candidate for next-generation sustainable lithium-ion batteries (LIBs) due to their high-capacity/operation voltage merits and elimination of expensive Co component. However, it is extremely challenging to solve the issues involving their intrinsic chemo-mechanical instabilities triggered by anisotropic lattice stress and short cycle life. Herein, we rationally incorporate tiny quintuple high-valence cations to engineer an entropy-assisted LiNiMnNbWSbTaMoO (denoted as EL-N9-3) as a competitive cathode for LIBs.

Multi-Level Engineering from Surface to Bulk Enabling Highly Stable Ni-Rich O3-Type Cathode toward Temperature-Tolerant Quasi-Solid-State Na-Ion Batteries.

The pursuit of high-capacity Na-ion batteries (NIBs) has propelled great forward the O3-type Ni-rich NaNiCoMnO (NCM) cathodes. However, the inborn chemo-mechanical instabilities caused by complex phase transitions and anisotropic lattice stress have severely delayed its widespread application. In the contribution, a cooperative surface-to-bulk modification strategy, i.

General and Fast Gas-Solid Synthesis of Functional MXenes and Derivatives on the Scale of Tens of Grams.

The rising of MXenes not only enriches the two-dimensional material family but also brings more opportunities for diverse functional applications. However, the controllable synthesis of MXenes is still unsatisfied via the common liquid-solid etching route, considering the unsolved problems like safety risk, time cost and easy oxidation. Herein, a facile yet efficient gas-solid (G-S) reaction methodology is devised by using hydrogen fluoride gas derived from fluorinated organics as the MAX etchant toward high-efficiency fabrication of multiple MXenes and their derivatives.

Self-sacrifice template construction of a conductive Cu(HHTP) nanowhisker arrays@copper foam toward robust lithium storage.

Nanowhisker-like Cu(HHTP) composed of neat arrays grown on a copper foam is rationally designed and prepared using Cu(OH) nanowire arrays as a self-sacrifice template. Benefiting from the good conductivity of Cu(HHTP) and an ordered array structure, the optimized Cu(HHTP)@CF-3 electrode exhibits high area capacity, good rate performance and cyclic stability.

Ultra-Sensitive Simultaneous Detection of Dopamine and Acetaminophen over Hollow Porous AuAg Alloy Nanospheres.

Hollow porous AuAg nanospheres (AuAg HPNSs) were obtained through a simple solvothermal synthesis, complemented by a dealloying strategy. The hollow interior, open pore voids, and integral interconnected skeleton shell in AuAg HPNSs are beneficial for providing sufficient electrolyte diffusion and contacts, abundant active sites, and efficient electron transport. This specific structure and the favorable alloy synergism contribute to the superior electrocatalytic activity toward dopamine (DA) and acetaminophen (AC).

High-entropy doping promising ultrahigh-Ni Co-free single-crystalline cathode toward commercializable high-energy lithium-ion batteries.

The development of advanced layered Ni-rich cathodes is essential for high-energy lithium-ion batteries (LIBs). However, the prevalent Ni-rich cathodes are still plagued by inherent issues of chemomechanical and thermal instabilities and limited cycle life. For this, here, we introduce an efficient approach combining single-crystalline (SC) design with in situ high-entropy (HE) doping to engineer an ultrahigh-Ni cobalt-free layered cathode of LiNiMnMgFeTiMoNbO (denoted as HE-SC-N88).

Versatile Separators Toward Advanced Lithium-Sulfur Batteries: Status, Recent Progress, Challenges and Perspective.

Lithium-sulfur batteries (LSBs) have recently gained extensive attention due to their high energy density, low cost, and environmental friendliness. However, serious shuttle effect and uncontrolled growth of lithium dendrites restrict them from further commercial applications. As "the third electrode", functional separators are of equal significance as both anodes and cathodes in LSBs.

Multifunctional Vanadium Nitride-Modified Separator for High-Performance Lithium-Sulfur Batteries.

Lithium-sulfur batteries (LSBs) are recognized as among the best potential alternative battery systems to lithium-ion batteries and have been widely investigated. However, the shuttle effect has severely restricted the advancement in their practical applications. Here, we prepare vanadium nitride (VN) nanoparticles grown in situ on a nitrogen-doped carbon skeleton (denoted as VN@NC) derived from the MAX phase and use it as separator modification materials for LSBs to suppress the shuttle effect and optimize electrochemical performance.

Synchronous embedded growth of MoC nanodisk arrays immobilized on porous carbon nanosheets for ultra-stable sodium storage.

Sodium ion capacitors (SICs) that combine the merits of both rechargeable batteries and supercapacitors have gained widespread recognition for their high energy density and extended cycle life as new energy storage devices. However, the purposeful design of advanced battery-type anodes has become an urgent need to remedy the dynamics mismatch with the capacitive cathode. Herein, we propose a simple but efficient bottom-up approach to build three-dimensional MoC/C hybrid architectures as anodes for SICs.

Construction of Ultrastable Ultrathin Black Phosphorus Nanodisks Hybridized with Fe O Nanoclusters and Iron (V)-Oxo Complex for Efficient Potassium Storage.

The practical application of metalloid black phosphorus (BP) based anodes for potassium ion batteries is mainly impeded by its instability in air and irreversible/sluggish potassium storage behaviors. Herein, a 2D composite is purposefully conceptualized, where ultrathin BP nanodisks with Fe O nanoclusters are hybridized with Lewis acid iron (V)-oxo complex (FC) nanosheets (denoted as BP@Fe O -NCs@FC). The introduced electron coordinate bridge between FC and BP, and hydrophobic surface of FC synergistically assure that BP@Fe O -NCs@FC is ultrastable in humid air.

Facile Construction of Porous ZnMnO Hollow Micro-Rods as Advanced Anode Material for Lithium Ion Batteries.

Spinel ZnMnO is considered a promising anode material for high-capacity Li-ion batteries due to their higher theoretical capacity than commercial graphite anode. However, the insufficient cycling and rate properties seriously limit its practical application. In this work, porous ZnMnO hollow micro-rods (ZMO HMRs) are synthesized by a facile co-precipitation method coupled with annealing treatment.

Chemomechanically Stable Small Single-crystal Mo-doped LiNi Co Mn O Cathodes for Practical 4.5 V-class Pouch-type Li-ion Batteries.

High voltage can cost-effectively boost energy density of Ni-rich cathodes based Li-ion batteries (LIBs), but compromises their mechanical, electrochemical and thermal-driven stability. Herein, a collaborative strategy (i.e.

High-efficiency and simple synthesis of TiCT nanoscrolls by surface energy modulation and cryogenic freezing.

To alleviate the restacking issue of 2D TiCT itself, we purposefully explore a simple but efficient method for controllable construction of 1D TiCT nanoscrolls with a high efficiency of ∼90.5%, with detailed regulation of the feed concentrations and surface energy of TiCT . The involved transformation mechanism from 2D nanosheets to 1D nanoscrolls is reasonably proposed.

Recent Progress of Carbon-Based Anode Materials for Potassium Ion Batteries.

With the increasing demand for clean energy, rechargeable batteries with K as carriers have attracted wide attention due to their advantages of expandability and low cost. High-performance anode materials are the key to the development of potassium ion batteries (PIBs), improving their competitiveness and feasibility. Carbon materials have become promising anodes for PIBs due to their abundant resources, low cost, non-toxicity and electrochemical diversity.

Ultrasonic-Assisted Synthesis of N-Doped, Multicolor Carbon Dots toward Fluorescent Inks, Fluorescence Sensors, and Logic Gate Operations.

Over past decades, the multicolor carbon dots (M-CDs) have attracted enormous attentions due to their tunable photoluminescence and versatile applications. Herein, the nitrogen-doped (N-doped) M-CDs including green, chartreuse, and pink emissive CDs are successfully synthesized by ultrasonic treatment of kiwifruit juice with different additive reagents such as ethanol, ethylenediamine, and acetone. Owing to their strong fluorescence upon irradiation with 365 nm UV light, the highly water-soluble M-CDs present great potential in the anticounterfeit field as fluorescent inks.

Single-Crystal Nano-Subunits Assembled Accordion-Shape WNb O Framework with High Ionic/Electronic Conductivities towards Li-Ion Capacitors.

Recently, Li-ion capacitors (LICs) have drawn tremendous attention due to their high energy/power density along with long cycle life. Nevertheless, the slow kinetics and stability of the involved anodes as bottleneck barriers always result in the modest properties of devices. The exploration of advanced anodes with both high ionic and electronic conductivities as well as structural stability thus becomes more significant for practical applications of LICs.

MOFs Derived Hetero-ZnO/FeO Nanoflowers with Enhanced Photocatalytic Performance towards Efficient Degradation of Organic Dyes.

It is still a challenge for wastewater treatment to develop efficient yet low-cost photocatalysts on a large scale. Herein, a facile yet efficient method was devised to successfully synthesize ZnO/FeO nanoflowers (NFs) by using metal organic framework ZIF-8 as the precursor. The photocatalytic activities of the as-prepared hetero-ZnO/FeO NFs are purposefully evaluated by photocatalytic degradation of methylene blue (MB) and methyl orange (MO) under UV light irradiation.

Recent Progress on In Situ/Operando Characterization of Rechargeable Alkali Ion Batteries.

The specific chemical and physical evolutions of electrode materials under operating conditions should be understood to optimize their electrochemical performances. The in-situ/operando techniques including Raman spectrum, transmission electron microscope, X-ray diffraction, X-ray absorption spectrum, and magnetization are powerful tools, which can provide the real-time surficial/interfacial changes of electrodes, the transformation of crystal lattice structures, the adjustment of electronic states and even the influence of magnetic properties under operating conditions. In this Review, the advantages and limitations of these in-situ/operando techniques in investigating the inner energy storage mechanisms of various type electrode materials are analyzed.

Organic-Inorganic Hybridization Engineering of Polyperylenediimide Cathodes for Efficient Potassium Storage.

Polyperylenediimide (PDI) is always subject to its modest conductivities, limited reversible active sites and inferior stability for potassium storage. To address these issues, herein, we firstly propose an organic-inorganic hybrid (PDI@Fe-Sn@N-Ti C T ), where Fe/Sn single atoms are bound to the N-doped MXenes (N-Ti C T ) via the unsaturated Fe/Sn-N bonds, and functionalized with PDI via d-π hybridization, forming a high conjugated δ skeleton. The resulted hybrid cathode endowed with enhanced electronic/ionic conductivities, lowered dissociation barriers of multiple redox centers and a stable cathode electrolyte interphase layer displays a 14-electron involved high-rate capacities and long cycle life.

Unveiling Intrinsic Potassium Storage Behaviors of Hierarchical Nano Bi@N-Doped Carbon Nanocages Framework via In Situ Characterizations.

Metallic bismuth has drawn attention as a promising alloying anode for advanced potassium ion batteries (PIBs). However, serious volume expansion/electrode pulverization and sluggish kinetics always lead to its inferior cycling and rate properties for practical applications. Therefore, advanced Bi-based anodes via structural/compositional optimization and sur-/interface design are needed.

Understanding the crystal structure-dependent electrochemical capacitance of spinel and rock-salt Ni-Co oxides density function theory calculations.

The spinel NiCoO and rock-salt NiCoO have been well established as attractive electrodes for supercapacitors. However, what is the intrinsic role of the congenital aspect, , crystal structure and the surface and/or near-surface controlled electrochemical redox behaviors, if the acquired features (, morphology, specific surface area, pore structure, and so on) are wholly ignored? Herein, we purposefully elucidated the underlying influences of unique crystal structures of NiCoO and NiCoO on their pseudocapacitance from mechanism analysis through the density function theory based first-principles calculations, along with the experimental validation. Systematic theoretical calculation and analysis revealed that more charge carriers near the Fermi-level, stronger affinity with OH in the electrolyte, easier deprotonation process, and the site-enriched characteristic for low-index surfaces of NiCoO enable its faster redox reaction kinetics and greater charge transfer, when compared to the spinel NiCoO.

Recent Progress in "Water-in-Salt" Electrolytes Toward Non-lithium Based Rechargeable Batteries.

Aqueous non-lithium based rechargeable batteries are emerging as promising energy storage devices thanks to their attractive rate capacities, long-cycle life, high safety, low cost, environmental-friendliness, and easy assembly conditions. However, the aqueous electrolytes with high ionic conductivity are always restricted by their intrinsically narrow electrochemical window. Encouragingly, the highly concentrated "water-in-salt" (WIS) electrolytes can efficiently expand the stable operation window, which brings up a series of aqueous high-voltage rechargeable batteries.

Facile Solvothermal Synthesis of Hollow BiOBr Submicrospheres with Enhanced Visible-Light-Responsive Photocatalytic Performance.

In this work, hierarchical hollow BiOBr submicrospheres (HBSMs) were successfully prepared a facile yet efficient solvothermal strategy. Remarkable effects of solvents upon the crystallinities, morphologies, and microstructures of the BiOBr products were systematically investigated, which revealed that the glycerol/isopropanol volumetric ratio played a significant role in the formation of hollow architecture. Accordingly, the underlying formation mechanism of the hollow submicrospheres was tentatively put forward here.

Construction of a multi-dimensional flexible MnS based paper electrode with ultra-stable and high-rate capability towards efficient sodium storage.

Recently, there has been an urgent need for flexible and low cost rechargeable batteries for the emerging flexible and wearable electronic devices. Herein, MnS nanoparticles embedded in carbon nanowires/reduced graphene oxide (MnS@CNWs/rGO) composite paper were synthesized via a simple yet scalable strategy with Mn based coordination nanowires and graphene oxide as precursors. The combination of multi-dimensional subunits offers not only a robust structure but also abundant pathways for fast electron/ion diffusion.