Holey etching strategy of siloxene nanosheets to improve the rate performance of photo-assisted Li-O batteries.

Improving the rate performance is of great significance to achieve high-performance photo-assisted Li-O batteries for developing new optimized bifunctional photocatalysts. Herein, a holey etching strategy is developed to prepare porous siloxene nanosheets with a size of 10 nm and few layers (P-siloxene NSs) by a modified Ag-assisted chemical etching method, and the optimized pore-forming conditions are: Ag ion concentration 0.01 mol dm, HF concentration 0.

Strong Electronic Interaction in High-Entropy Oxide Enhances Oxygen Evolution Reaction.

High-entropy oxides are a new type of material with significant application potential. However, the lack of a universal HEO preparation method severely limits the property study and application of HEOs. Herein, we report a universal approach of spray pyrolysis for the preparation of various HEOs and study the electrocatalytic performance of HEOs toward the oxygen evolution reaction.

Dual-Modified Electrospun Fiber Membrane as Separator with Excellent Safety Performance and High Operating Temperature for Lithium-Ion Batteries.

Polyacrylonitrile/Boric acid/Melamine/the delaminated BN nanosheets electrospun fiber membrane (PBNBN) with excellent mechanical property, high thermal stability, superior flame-retardant performance, and good wettability are fabricated by electrospinning PAN/DMF/HBO/CHN/ the delaminated BN nanosheets (BNNSs) homogeneous viscous suspension and followed by a heating treatment. BNNSs are obtained by delaminating the bulk h-BN in isopropyl alcohol (IPA) with an assistance of Polyvinylpyrrolidone (PVP). Benefiting from the cross-linked pore structure and high-temperature stability of BNNSs, PBNBN electrospun fiber membrane delivers high thermal dimensional stability (almost no size contraction at 200 °C), excellent mechanical property (19.

Boron Quantum Dots Pillared Ti C T Membrane Electrode with High Rate Performance for Supercapacitor.

A sonication-assisted liquid-phase preparation technique is developed to prepare boron quantum dots (BQDs) with a lateral size of 3 nm in a solution of NMP and NBA; it shows a direct bandgap semiconductor with a bandgap of 3 eV and a specific capacitance of 41 F g . A BQDs(10)-Ti C T membrane electrode with excellent capacitance and high flexibility is prepared by using Ti C T nanosheets (NSs) as assembled units and BQDs as pillar; it gives a specific capacitance of 524 F g at 1 A g in 6 m H SO electrolyte, a high capacity retention of 75%, and a minimum relaxation time of 0.51 s.

Size-Controlled Boron-Based Bifunctional Photocathodes for High-Efficiency Photo-Assisted Li-O Batteries.

Photo-assisted Li-O batteries are introduced as a promising strategy for reducing severe overpotential by directly employing photocathodes. Herein, a series of size-controlled single-element boron photocatalysts are prepared by the meticulous liquid phase thinning methods by combining probe and water bath sonication, and their bifunctional photocathodes in the photo-assisted Li-O batteries are systematically investigated. The boron-based Li-O batteries have shown incremental round-trip efficiencies as the sized reduction of boron under illumination.

All-solid-state TiCT neutral symmetric fiber supercapacitors with high energy density and wide temperature range.

All-solid-state TiCT neutral symmetric fiber supercapacitors (PVA EGHG TiCT FSCs) with high energy density and wide temperature range are constructed by using polyvinyl alcohol (PVA)-ethylene glycol hydrogel (EGHG)-sodium perchlorate (NaClO) as electrolyte and separator, and TiCT fiber as electrodes. TiCT fiber is prepared using 130 mg mL TiCT nanosheet ink as an assembly unit in a coagulation bath of isopropyl alcohol (IPA) and distilled water with 5 wt% CaCl by a wet spinning method. The prepared TiCT fiber exhibits a specific capacity of 385 F cm and a capacitance retention of 94 % after 10,000 cycles in 1 M NaClO electrolyte.

Atomically Dispersed Fe-N Sites and NiFe-LDH Sub-Nanoclusters as an Excellent Air Cathode for Rechargeable Zinc-Air Batteries.

The sluggish four-electron processes of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) limit the development of rechargeable Zn-air batteries (RZABs). Highly efficient ORR/OER bifunctional electrocatalysts are therefore highly desired for the commercialization of RZABs in large scale. Herein, the Fe-N-C (ORR active sites) and NiFe-LDH clusters (OER active sites) are successfully integrated within a NiFe-LDH/Fe,N-CB electrocatalyst.

Single-crystalline Mg-substituted NaMn(PO)PO nanoparticles as a high capacity and superior cycling cathode for sodium-ion batteries.

Mn-based mixed phosphate NaMn(PO)(PO) (NMPP) is a promising cathode for high-potential, low-cost and eco-friendly sodium-ion batteries. However, this material still faces some bottleneck issues in terms of low conductivity, disturbance of impure crystalline phase, micron-sized agglomerated particles and the Mn Jahn-Teller effect. Herein, a Mg-substituted NMPP (NMMgPP)@C composite was constructed modified solution combustion and subsequent calcination treatment.

Synergy Effect of High-Stability of VS Nanorods for Sodium Ion Battery.

Sodium-ion batteries (SIBs) have attracted increasing interest as promising candidates for large-scale energy storage due to their low cost, natural abundance and similar chemical intercalation mechanism with lithium-ion batteries. However, achieving superior rate capability and long-life for SIBs remains a major challenge owing to the limitation of favorable anode materials selection. Herein, an elegant one-step solvothermal method was used to synthesize VS nanorods and VS nanorods/reduced graphene oxide (RGO) nanocomposites.

Direct growth of SnS nanowall photoanode for high responsivity self-powered photodetectors.

Tin sulfide (SnS) has attracted growing attention due to its environmental friendliness, tunable band gap and potential applications for high-sensitivity photodetectors. However, the low responsivity and slow response speed severely hinder its further applications. In this work, SnS nanowalls have been successfully fabricated on FTO substrates by a facile hydrothermal approach.

Few-layer Mg-deficient borophene nanosheets: I oxidation and ultrasonic delamination from MgB.

By using I as an oxidant and CHCN as a reaction medium, few-layer Mg-deficient borophene nanosheets (FBN) with a stoichiometric ratio of MgB are prepared by oxidizing MgB in a mixture of CHCN and HCl for 14 days under nitrogen protection and followed by ultrasonic delaminating in CHCN for 2 h. The prepared FBN possess a two-dimensional flake morphology, and they show a clear interference fringe with a -spacing of 0.251 nm corresponding to the (208) plane of rhombohedral boron.

Ultrahigh-energy sodium ion capacitors enabled by the enhanced intercalation pseudocapacitance of self-standing TiNbO/CNF anodes.

In order to increase the capacity and improve the sluggish Na-reaction kinetics of anodes as sodium ion capacitors (SICs), a TiNbO/CNF self-standing film electrode comprised of TiNbO nanosheets and carbon nanofibers has been fabricated electrospinning HTiNbO nanosheets with PAN and subsequent carbonization treatment. The as-prepared TiNbO/CNF film electrode possesses fast Na-ion intercalation kinetics and high conductivity during Na-ion storage, and it displays a high reversible capacity of 324 mA h g at 0.1 A g.

A Queue-Ordered Layered Mn-Based Oxides with Al Substitution as High-Rate and High-Stabilized Cathode for Sodium-Ion Batteries.

Development of highly stabilized and reversible cathode materials has become a great challenge for sodium-ion batteries. O'3-type layered Mn-based oxides have deserved much attention as one of largely reversible-capacity cathodes featured by the resource-rich and low-toxic elements. However, the fragile slabs structure of typical layered oxides, low Mn-ion migration barriers, and Jahn-Teller distortion of Mn have easily resulted in the severe degradation of cyclability and rate performances.

Few-layer and large flake size borophene: preparation with solvothermal-assisted liquid phase exfoliation.

The preparation of two-dimensional boron (B) nanosheets, especially for borophene, is still a challenge because of its unique structure and complex B-B bonds in bulk boron. In the present work, a novel preparation technology for borophene with only a few layers and large flake sizes is developed by a solvothermal-assisted liquid phase exfoliation process, consisting of ball milling-thinning, solvothermal swelling, and probe ultrasonic delamination. The exfoliation effect of the bulk B precursors is related to the surface tension and Hildebrand parameter of the selected solvents such as acetone, ,-dimethyl formamide (DMF), acetonitrile, ethanol, and -methyl pyrrolidone (NMP), and a relative small surface tension when using solvents is favorable for the exfoliation of bulk B.

Electrospun NbO nanorods/microporous multichannel carbon nanofiber film anode for Na ion capacitors with good performance.

For the disadvantages of both the slow reaction kinetics and the poor conductivity for NbO electrode materials as sodium-ion capacitors (SICs), NbO NRs/NMMCNF film electrode with good flexibility and high electrochemical property has been fabricated by electrospinning PAN/PMMA/HNbO·HO homogeneous viscous suspension and followed by an annealing treatment, in which the precursor HNbO·HO nanorods are obtained by grinding HNbO·HO nanowires, and NbO nanorods are uniformly embedded in nitrogen doped microporous multichannel carbon nanofiber. Benefiting from the multichannel network structure, NbO NRs/NMMCNF film electrode delivers the fast kinetics of Na-storage and the superior Na-ion storage performance, it delivers outstanding rate capability (101 mAh g at 4 A g) and ultralong lifespan (91% capacity retention after 10,000 cycles at 2 A g). A NbO NRs/NMMCNF//AC SIC based on the NbO NRs@NMMCNF fiber film anode and the AC cathode is assembled.

TiCT Nanosheets/TiCT Quantum Dots/RGO (Reduced Graphene Oxide) Fibers for an All-Solid-State Asymmetric Supercapacitor with High Volume Energy Density and Good Flexibility.

By using TiCT quantum dots as interlayer spacers, TiCT nanosheets/TiCT quantum dots/RGO (reduced graphene oxide) fiber (MMRG) is prepared by a wet-spinning method; it shows good capacitance and excellent flexibility. The MMRG fiber electrode possesses a novel network structure and a maximum volumetric capacitance of 542 F cm, and its capacitance and flexibility are affected by the amount of TiCT quantum dots. Also, the TiCT/PEDOT:PSS [poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)] fiber (MP) is prepared by injecting a homogeneous suspension of TiCT nanosheets and PEDOT:PSS into a bath of 98 wt % HSO.

NbO Nanoparticles Anchored on an N-Doped Graphene Hybrid Anode for a Sodium-Ion Capacitor with High Energy Density.

Sodium-ion capacitors (SICs) have gained great interest for mid- to large-scale energy storage applications because of their high energy and high power densities as well as long cycle life and low cost. Herein, a T-NbO nanoparticles/N-doped graphene hybrid anode (T-NbO/NG) was prepared by solvothermal treating a mixed ethanol solution of graphene oxide (GO), urea, and NbCl at 180 °C for 12 h, followed by calcining at 700 °C for 2 h, in which T-NbO nanoparticles with average size of 17 nm were uniformly anchored on the surface of the nitrogen-doped reduced GO because their growth and aggregation were hindered, and also, the electronic conductivity and the active sites of T-NbO/NG were improved by doping nitrogen. The T-NbO/NG anode showed superior rate capability (68 mA h g even at 2 A g) and good cycling life (106 mA h g at 0.

Facile preparation of partially reduced graphite oxide nanosheets as a binder-free electrode for supercapacitors.

Preparation of graphene (GR) based electrode materials with excellent capacitive properties is of great importance to supercapacitors. Herein, we report a facile approach to prepare partially reduced graphite oxide (PRG) nanosheets by reducing graphite oxide (GO) using commercial CuO powder as a reduction agent, moreover, we demonstrate that the PRG nanosheets can act as building blocks for assembling hydrogels (PRGH) and flexible film (PRGF). The obtained PRGH and PRGF can be directly used as binder-free electrodes for supercapacitors and give high specific capacitance (292 and 273 F g at a current density of 0.

Free-standing graphene/bismuth vanadate monolith composite as a binder-free electrode for symmetrical supercapacitors.

Preparation of new types of electrode material is of great importance to supercapacitors. Herein, a graphene/bismuth vanadate (GR/BiVO) free-standing monolith composite has been prepared a hydrothermal process. Flexible GR sheets act as a skeleton in the GR/BiVO monolith composites.

CoNi S Nanoparticle/Carbon Nanotube Sponge Cathode with Ultrahigh Capacitance for Highly Compressible Asymmetric Supercapacitor.

Compared with other flexible energy-storage devices, the design and construction of the compressible energy-storage devices face more difficulty because they must accommodate large strain and shape deformations. In the present work, CoNi S nanoparticles/3D porous carbon nanotube (CNT) sponge cathode with highly compressible property and excellent capacitance is prepared by electrodepositing CoNi S on CNT sponge, in which CoNi S nanoparticles with size among 10-15 nm are uniformly anchored on CNT, causing the cathode to show a high compression property and gives high specific capacitance of 1530 F g . Meanwhile, Fe O /CNT sponge anode with specific capacitance of 460 F g in a prolonged voltage window is also prepared by electrodepositing Fe O nanosheets on CNT sponge.

Preparation and formation process of α-MnS@MoS microcubes with hierarchical core/shell structure.

α-MnS@MoS microcubes with hierarchical core/shell structure are prepared by one-step hydrothermal method in a reaction system of δ-MnO nanowires, thioacetamide and NaMoO at 200°C for 24h, and the formation process and phase transition behavior has been investigated in detail. Research results indicate that uniform nanosheets of MoS with thickness of about 20nm and size up to hundreds of nanometers are vertically grow on the surface of α-MnS core, and the amount of sodium molybdate plays a crucial role in adjusting the crystal phase and structure of the obtained materials. The formation process of α-MnS@MoS microcubes with hierarchical core/shell structure consist of four stages, δ-MnO nanowires with layered structure are firstly transforms into tetragonal MnO nanoparticles, then into γ-MnS hexagonal prisms and α-MnS microcubes, and finally into α-MnS@MoS microcubes.

Rational design and controllable preparation of holey MnO nanosheets.

A novel technique for the design and controllable preparation of holey MnO nanosheets was first developed by an in situ redox reaction between the MnO nanosheets and adsorbed Fe ions at room temperature, in which Fe ions originated from a redox reaction between Cu wire and Fe ions. The formation of in-plane nanopores on the MnO nanosheets obviously improved the rate capability when they were used as promising supercapacitor electrodes.