A Multifunctional Secondary Based on Heterogeneous Co-MnO@NC for Depth-Induced Deposition and Conversion of Polysulfides in Li─S Batteries.

The conductive carbon-based interlayer, as the secondary current collector in the self-dissolving battery system, can effectively capture escaping cathode active materials, inducing deep release of remaining capacity. In the multi-step reactions of Li─S batteries, the environmental tolerance of the conductive carbon-based interlayer to polysulfides determines the inhibition of shuttle effects. Here, a modified metal-organic framework (Mn-ZIF67) is utilized to obtain nitrogen-doped carbon-coated heterogeneous Co-MnO (Co-MnO@NC) with dual catalytic center for the functional interlayer materials.

The shield-like nano-sized SiN derivatives to defend against the attack of lithium dendrites.

The unrestrained Li dendrite growth impedes the performance of Li metal batteries (LMBs) and brings safety concerns. To mitigate the unfavorable effect of Li dendrites, in this work, a shield-like artificial interlayer composed of SiN is employed to achieve the desirable electrochemical performance of LMBs. The SiN-based interlayer can in-situ electrochemically react with Li to generate inorganic LiN and LiSi alloys: the former with high ionic conductivity can effectively enhance the Li transference, while the latter with reversibility for Li insertion/deinsertion can act as Li reservoir to modulate Li platting/stripping.

The inhibited Li dendrite growth via bulk/liquid dual-phase modulation.

Li metal is a potential anode material for the next generation high-energy-density batteries because of its high theoretical specific capacity. However, the inhomogeneous lithium dendrite growth restrains corresponding electrochemical performance and brings safety concerns. In this contribution, the LiBi/LiO/LiI fillers are generated by the in-situ reaction between Li and BiOI nanoflakes, which promises corresponding Li anodes (BiOI@Li) showing favorable electrochemical performance.

"Grafting" NiSe onto CuSe with twinborn structure embedded in carbon-based nanofibers to weave freestanding sodium-ion storage electrode.

The fabrication of freestanding electrodes for Na storage is necessary to achieve high energy density. However, the large radius of Na results in a large volume fluctuation and sluggish reaction kinetics of active materials, particularly at a high active material content, thereby impeding electrochemical performance with undesirable cycling performance or rate capability. In this study, a freestanding electrode based on the "NiSe grafted on CuSe" heterostructure with double-carbon protective shells (NiSe/CuSe@C@NCNFs) was successfully constructed for Na storage.

The Inducement and "Rejuvenation" of Li Dendrites by Space Confinement and Positive Fe/Co-Sites.

The high reactivity of Li metal and the inhomogeneous Li deposition leads to the formation of Li dendrites and "dead" Li, which impedes the performance of Li metal batteries (LMBs) with high energy density. The regulating and guiding the Li dendrite nucleation is a desirable tactic to realize concentrated distribution of Li dendrites instead of completely inhibiting dendrite formation. Here, a Fe-Co-based Prussian blue analog with hollow and open framework (H-PBA) is employed to modify the commercial polypropylene separator (PP@H-PBA).

LiBi/LiF/LiO derived from mechanical rolling of Li metal with BiOF nanoplates as stable filler for dendrite-free Li metal batteries.

Li is attractive anode for next-generation high-energy batteries. The high chemical activity, dendrite growth, and huge volume fluctuation of Li hinder its practical application. In this work, a Li-BiOF composite anode (LBOF) is obtained by combining Li metal with BiOF nanoplates through facile folding and mechanical cold rolling.

Promoting Ge Alloying Reaction via Heterostructure Engineering for High Efficient and Ultra-Stable Sodium-Ion Storage.

Germanium (Ge)-based materials have been considered as potential anode materials for sodium-ion batteries owing to their high theoretical specific capacity. However, the poor conductivity and Na diffusivity of Ge-based materials result in retardant ion/electron transportation and insufficient sodium storage efficiency, leading to sluggish reaction kinetics. To intrinsically maximize the sodium storage capability of Ge, the nitrogen doped carbon-coated CuGe/Ge heterostructure material (CuGe/Ge@N-C) is developed for enhanced sodium storage.

Constructing CoS Nanosheets Coating N-Doped Carbon Nanofibers as Freestanding Sulfur Host for High-Performance Lithium-Sulfur Batteries.

Lithium-sulfur batteries (LSBs) have shown great potential as a rival for next generation batteries, for its relatively high theoretical capacity and eco-friendly properties. Nevertheless, blocked by the shuttle effect of lithium polysulfides (LPSs, LiS-LiS) and insulation of sulfur, LSBs show rapid capacity loss and cannot achieve the practical application. Herein, a composite of carbon nanofibers coated by CoS nanosheets (denoted as CNF@CoS) is successfully synthesized as freestanding sulfur host to optimize the interaction with sulfur species.

FeSe encapsulated in N-doped carbon nanofibers as a stable anode material for sodium ion batteries.

Transition metal chalcogenides especially Fe-based selenides for sodium storage have the advantages of high electric conductivity, low cost, abundant active sites, and high theoretical capacity. Herein, we proposed a facile synthesis of FeSe embedded in carbon nanofibers (denoted as FeSe-NCFs). The FeSe-NCFs with a 1D electron transfer network can facilitate Na transportation to ensure fast reaction kinetics.

Highly conductive VC embedded in carbon matrix as effective trapper and catalyst for Li-S batteries.

Vanadium carbide embedded in a nitrogen-doped carbon matrix (VC@NCM) is synthesized as a 3D freestanding sulfur host. Owing to the high electrical conductivity (1.6 × 10 S cm) of VC and strong chemisorption and catalytic effect on sulfur species, Li-S batteries with VC@NCM deliver enhanced redox kinetics with ultralow capacity decay of 0.

Conductive FeOOH as Multifunctional Interlayer for Superior Lithium-Sulfur Batteries.

The commercial course of Li-S batteries (LSBs) is impeded by several severe problems, such as low electrical conductivity of S, Li S , and Li S, considerable volume variation up to 80% during multiphase transformation and severe intermediation lithium polysulfides (LiPSs) shuttle effect. To solve above problems, conductive FeOOH interlayer is designed as an effective trapper and catalyst to accelerate the conversion of LiPSs in LSBs. FeOOH nanorod is effectively affinitive to S that Fe atoms act as Lewis acid sites to capture LiPSs via strong chemical anchoring capability and dispersion interaction.

A Full Li-S Battery with Ultralow Excessive Li Enabled via Lithiophilic and Sulfilic W C Modulation.

The practical application of Li-S batteries demands low cell balance (Li /S ), which involves uniform Li growth, restrained shuttle effect, and fast redox reaction kinetics of S species simultaneously. Herein, with the aid of W C nanocrystals, a freestanding 3D current collector is applied as both Li and S hosts owing to its lithiophilic and sulfilic property. On the one hand, the highly conductive W C can reduce Li nucleation overpotentials, thus guiding uniform Li nucleation and deposition to suppress Li dendrite growth.

MnSe embedded in carbon nanofibers as advanced anode material for sodium ion batteries.

MnSe with high theoretical capacity and reversibility is considered as a promising material for the anode of sodium ion batteries. In this study, MnSe nanoparticles embedded in 1D carbon nanofibers (MnSe-NC) are successfully prepared via facile electrospinning and subsequent selenization. A carbon framework can effectively protect MnSe dispersed in it from agglomeration and can accommodate volume variation in the conversion reaction between MnSe and Na to guarantee cycling stability.

Hematite photoanode modified with inexpensive hole-storage layer for highly efficient solar water oxidation.

Hematite is recognized as an excellent photocatalyst for photoelectrochemical photoanodes for water oxidation because of its favorable band gap, excellent anti-photocorrosion and structural stability in alkaline solution. However, slow charge transport and fast carrier recombination in the bulk and at the hematite photoanode/electrolyte interface, have limited its applications for water splitting. Herein, we report a highly efficient hematite/ferrhydrite (Fh) core-shell photoanode system, consisting of hematite (α-FeO) semiconductor nanorods which dramatically enhance light harvesting, and ferrhydrite as the hole-storage shell.

CoVO Nanoparticles Supported on Reduced Graphene Oxide for Efficient Lithium Storage.

CoVO (CVO) with high theoretical specific capacity derived from the multiple oxidation states of V and Co is regarded as a potential electrode material for lithium-ion batteries (LIBs). Herein, reduced graphene oxide (rGO)-supported ultrafine CVO (rGO@CVO) nanoparticles are successfully prepared via the hydrothermal and subsequent annealing processes. The CVO supported on 2D rGO nanosheets possess excellent structural compatibility for the accommodation of volume variation to maintain the structural integrity of an electrode during the repeated lithiation/delithiation process.

CuSe Nanoparticles Encapsulated by Nitrogen-Doped Carbon Nanofibers for Efficient Sodium Storage.

CuSe with high theoretical capacity and good electronic conductivity have attracted particular attention as anode materials for sodium ion batteries (SIBs). However, during electrochemical reactions, the large volume change of CuSe results in poor rate performance and cycling stability. To solve this issue, nanosized-CuSe is encapsulated in 1D nitrogen-doped carbon nanofibers (CuSe-NC) so that the unique structure of 1D carbon fiber network ensures a high contact area between the electrolyte and CuSe with a short Na diffusion path and provides a protective matrix to accommodate the volume variation.

Double Morphology of CoS Coated by N, S Co-doped Carbon as Efficient Anode Materials for Sodium-Ion Batteries.

CoS is a potential anode material for its high sodium storage performance, easy accessibility, and thermostability. However, the volume expansion is a great hindrance to its development. Herein, a composite containing CoS nanofibers and hollow CoS nanospheres with N, S co-doped carbon layer (CoS@NSC) is successfully synthesized through a facile solvothermal process and a high-temperature carbonization.

Lotus Root-Like Nitrogen-Doped Carbon Nanofiber Structure Assembled with VN Catalysts as a Multifunctional Host for Superior Lithium-Sulfur Batteries.

Lithium-sulfur batteries (LSBs) are regarded as one of the most promising energy-recycling storage systems due to their high energy density (up to 2600 Wh kg), high theoretical specific capacity (as much as 1672 mAh g), environmental friendliness, and low cost. Originating from the complicated redox of lithium polysulfide intermediates, Li-S batteries suffer from several problems, restricting their application and commercialization. Such problems include the shuttle effect of polysulfides (LiS (2 < x ≤ 8)), low electronic conductivity of S/LiS/LiS, and large volumetric expansion of S upon lithiation.

Modified Nanopillar Arrays for Highly Stable and Efficient Photoelectrochemical Water Splitting.

Atomically modified graphitic carbon nitride quantum dots (QDs), characterized by strongly increased reactivity and stability, are developed. These are deposited on arrays of TiO nanopillars used as a photoanode for the photoelectrochemical water splitting. This photoanode shows excellent stability, with 111 h of continuous work without any performance loss, which outperforms the best-reported results by a factor of 10.

Enhanced Photocatalytic H Evolution over ZnInS Flower-Like Microspheres Doped with Black Phosphorus Quantum Dots.

In this work, black phosphorus quantum dots (BPQDs) were decorated on hexagonal ZnInS flower-like microspheres to form zero-dimensional/two-dimensional (0D/2D) structures. Interface interactions between the BPQDs and ZnInS resulted in optimum effective charge transfer, thereby improving the photocatalytic performance of the material. Thus, the 0.

The Ternary Heterostructures of BiOBr/Ultrathin g-C₃N₄/Black Phosphorous Quantum Dot Composites for Photodegradation of Tetracycline.

Herein, we synthesized BiOBr/ultrathin g-C₃N₄/ternary heterostructures modified with black phosphorous quantum dots using a simple water bath heating and sonication method. The ternary heterostructure was then used for the photocatalytic degradation of tetracycline in visible light, with an efficiency as high as 92% after 3 h of irradiation. Thus, the photodegradation efficiency is greatly improved compared to that of ultrathin g-C₃N₄, BiOBr, and black phosphorous quantum dots alone.

Flexible Freestanding Carbon Nanofiber-Embedded TiO Nanoparticles as Anode Material for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs), owning to the low cost, abundant resources, and similar physicochemical properties with lithium-ion batteries (LIBs), have earned much attention for large-scale energy storage systems. In this article, we successfully synthesize flexible freestanding carbon nanofiber-embedded TiO nanoparticles (CNF-TiO) and then apply it directly as anode in SIBs without binder or current collector. Taking the advantage of flexible CNF and high structural stability, this anode exhibits high reversible capacity of 614 mAh·g (0.

In Situ Synthesis of All-Solid-State Z-Scheme BiOBrI/Ag/AgI Photocatalysts with Enhanced Photocatalytic Activity Under Visible Light Irradiation.

A series of novel visible light driven all-solid-state Z-scheme BiOBrI/Ag/AgI photocatalysts were synthesized by facile in situ precipitation and photo-reduction methods. Under visible light irradiation, the BiOBrI/Ag/AgI samples exhibited enhanced photocatalytic activity compared to BiOBrI and AgI in the degradation of methyl orange (MO). The optimal ratio of added elemental Ag was 15%, which degraded 89% of MO within 20 min.

The fabrication of a 3D current collector with bitter melon-like TiO-NCNFs for highly stable lithium-sulfur batteries.

The conductive 3D freestanding N-doped carbon nanofibers (NCNFs) current collector was embedded with homogeneously polar TiO nanoparticles. This current collector used for the sulfur cathode exhibits strong chemical adsorption for hindering the shuttle effect of polysulfides, and demonstrates a high specific capacity of 865 mA h g at 0.2C and excellent cycle performance (200 cycles with capacity retention of 91%).