Na2V6O16·2.14H2O nanobelts as a stable cathode for aqueous zinc-ion batteries with long-term cycling performance

Aqueous zinc-ion batteries(ZIBs) have been considered as one of the most promising electrochemical devices for large-scale energy storage system owing to their low cost and high safety. Herein, Na2V6O16·2.14H2O nanobelts are synthesized and applied as cathode material for ZIBs. The sample displays a high capacity of 466 m Ahg^-1 at 100 mAg^-1 and stable cycling performance with a capacity retention of 90% over 20 0 0 cycles at the 20 Ag^-1. Moreover, Na2V6O16·2.14H2O presents a capable rate ability and a high energy density of 312 Wh kg^-1 at a specific power of 70 Wkg^-1. The superior electrochemical performance is attributed to the large interlayer spacing and outstanding structure stability, which promise the highly reversible intercalation and extraction of zinc ion. The electrochemical kinetics and zinc ion storage mechanism are also investigated. This work demonstrates that nanoscale electrode materials with large interlayer spacing can effectively enhance the electrochemical performance of aqueous ZIBs, which can be extended to other metal ion batteries, such as magnesium ion batteries and aluminum ion batteries.

Pampas grass-inspired FeOOH nanobelts as high performance anodes for sodium ion batteries

High-performance materials are the key to developing new alternative energy-storage systems[1-4].Sodium ion batteries(SIBs)are regarded as the promising large-scale electric energy storage owing to the high abundance and low cost of sodium resources[1,5-9].However,the sluggish kinetics of Na^(+)caused by the large-sized Na^(+)(1.02A)result in the lower energy density and unsatisfactory electrochemical properties[10-14].

Intercalating Ultrathin MoO_3 Nanobelts into MXene Film with Ultrahigh Volumetric Capacitance and Excellent Deformation for High-Energy-Density Devices

The restacking hindrance of MXene films restricts their development for high volumetric energy density of flexible supercapacitors toward applications in miniature,portable,wearable or implantable electronic devices.A valid solution is construction of rational heterojunction to achieve a synergistic property enhancement.The introduction of spacers such as graphene,CNTs,cellulose and the like demonstrates limited enhancement in rate capability.The combination of currently reported pseudocapacitive materials and MXene tends to express the potential capacitance of pseudocapacitive materials rather than MXene,leading to low volumetric capacitance.Therefore,it is necessary to exploit more ideal candidate materials to couple with MXene for fully expressing both potentials.Herein,for the first time,high electrochemically active materials of ultrathin MoO3 nanobelts are intercalated into MXene films.In the composites,MoO3 nanobelts not only act as pillaring components to prevent restacking of MXene nanosheets for fully expressing the MXene pseudocapacitance in acidic environment but also provide considerable pseudocapacitive contribution.As a result,the optimal M/MoO3 electrode not only achieves a breakthrough in volumetric capacitance(1817 F cm-3 and 545 F g-1),but also maintains good rate capability and excellent flexibility.Moreover,the corresponding symmetric supercapacitor likewise shows a remarkable energy density of 44.6 Wh L-1(13.4 Wh kg-1),rendering the flexible electrode a promising candidate for application in high-energy-density energy storage devices.

Controlled Growth and Cathodoluminescence Property of ZnS nanobelts with Large Aspect Ratio

ZnS nanobelts with large aspect ratio are successfully synthesized on a large scale through thermally evaporating of ZnS powder with a trace of SnO_2 powder using gold coated Si wafer as the substrate at 1100°C.The results indicate that the as-obtained ZnS nanobelts are about 10 nm in thickness and hundreds of micrometers in length,and the aspect ratio reaches more than 104.Substrate dependent experiments are conducted to better study the growth mechanism of the ZnS nanobelts.Subsequently,optical properties of the as-synthesized ZnS nanobelts are also investigated by using a cathodoluminescence(CL) system,which shows the existence of a strong ultraviolet emission at 342 nm and two poor emission peaks at 522 nm and 683 nm at room temperature,respectively.

Palladium Nanoparticles Loaded on Carbon Modified TiO_2 Nanobelts for Enhanced Methanol Electrooxidation

Carbon modified TiO_2 nanobelts(TiO_2-C) were synthesized using a hydrothermal growth method,as a support material for palladium(Pd) nanoparticles(Pd/TiO_2-C) to improve the electrocatalytic performance for methanol electrooxidation by comparison to Pd nanoparticles on bare TiO_2 nanobelts(Pd/TiO_2)and activated carbon(Pd/AC). Cyclic voltammetry characterization was conducted with respect to saturated calomel electrode(SCE) in an alkaline methanol solution, and the results indicate that the specific activity of Pd/TiO_2-C is 2.2 times that of Pd/AC and 1.5 times that of Pd/TiO_2. Chronoamperometry results revealed that the TiO_2-C support was comparable in stability to activated carbon, but possesses an enhanced current density for methanol oxidation at a potential of -0.2 V vs. SCE. The current study demonstrates the potential of Pd nanoparticle loaded on hierarchical TiO_2-C nanobelts for electrocatalytic applications such as fuel cells and batteries.

Layered barium vanadate nanobelts for high-performance aqueous zinc-ion batteries

Aqueous zinc-ion batteries(ZIBs)are deemed as the idea option for large-scale energy storage systems owing to many alluring merits including low manufacture cost,environmental friendliness,and high operations safety.However,to develop high-performance cathode is still significant for practical application of ZIBs.Herein,Ba_(0.23)V_(2)O_(5)·1.1H_(2)O(BaVO)nanobelts were fabricated as cathode materials of ZIBs by a typical hydrothermal synthesis method.Benefiting from the increased interlayer distance of 1.31 nm by Ba2+ and H2O pre-intercalated,the obtained BaVO nanobelts showed an excellent initial discharge capacity of 378 mAh·g^(-1) at 0.1 A·g^(-1),a great rate performance(e.g.,172 mAh·g^(-1) at 5 A·g^(-1)),and a superior capacity retention(93% after 2000 cycles at 5 A·g^(-1)).

Self-assemble Mechanism of Nickel Nanobelts Prepared by Sol-precipitation and Thermal Decomposition Route

Using the idea of material design and the design of reaction system and conditions,quasi-one-dimensional nano-materials with ribbon-like structure were successfully prepared.Nickel tartrate nanobelts were prepared by a sol-precipitation route,using nickel chloride hexahydrate and tartaric acid as raw materials,and using ammonium hydroxide as pH value modifier.Nickel nanobelts with smooth surface were prepared by a thermal-decomposition route at about 355℃for about 30 minutes,in CO_(2) atmosphere,using nickel tartrate nanobelts as precursor.The analyses of atomic absorption spectrometry(AAS),organic elemental analyzer(OEA),infrared spectroscopy(IR)and ultraviolet-visible spectroscopy(UV-Vis)indicate that the products as-prepared is nickel tartrate,which has octahedral configuration of co-ordination of nickel atoms.The images of scanning electron microscopy(SEM)indicate that the morphology of nickel tartrate as-prepared is an obvious belt structure with clear and smooth surface.The images of SEM also indicate that the nickel nanobelts have clear and smooth surface.The nickel nanobelts are about tens of micrometers in length,tens of nanometers in thickness,and 100-200 nanometers in width.

Monoclinic Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O nanobelts/reduced graphene oxide:A novel high-capacity and long-life composite for potassium-ion battery anodes

Developing suitable anode materials for potassium-ion batteries(PIBs)remains a great challenge owing to the limited theoretical capacity of active materials and large radius of K+ion(1.38?).To solve these obstacles,by integrating the principles of multielectron transfer and rational porous crystal framework,we creatively propose the monoclinic Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O(CVO)as a novel anode for PIBs.Furthermore,inspired by the metastable nature of CVO under high temperature/pressure,we skillfully design a facile hydrothermal recrystallization strategy without the phase change and surfactants addition.Thus,for the first time,the porous composite of Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O nanobelts covered in situ by reduced graphene oxide(CVO NBs/r GO)was assembled,greatly improving the deficiencies of CVO.When used as a novel anode for PIBs,CVO NBs/r GO delivers large specific capacity(up to 551.4 m Ah g^(-1)at 50 m A g^(-1)),high-rate capability(215.3 m Ah g^(-1)at 2.5 A g^(-1))and super durability(203.6 m Ah g^(-1)at 500 m A g^(-1)even after 1000 cycles).The outstanding performance can be ascribed to the synergistic merits of desirable structural features of monoclinic CVO nanobelts and the highly conductive graphene 3D network,thus promoting the composite material stability and electrical/ionic conductivity.This work reveals a novel metal vanadate-based anode material for PIBs,would further motivate the subsequent batteries research on M_(3)(OH)_(2)V_(2)O_(7)-n H_(2)O(M;Co,Ni,Cu,Zn),and ultimately expands valuable fundamental understanding on designing other high-performance electrode materials,including the combined strategies of multielectron transfer with rational porous crystal framework,and the composite fabrication of 1D electrode nanostructure with conductive carbon matrix.

ZnO Nanobelts: An Efficient Catalyst for Synthesis of 5-Arylidine-2,4-Thiazolidinediones and 5-Arylidine-Rhodanines

A facile preparation of ZnO nanobelts by chemical precipitation technique and its utility as catalyst in Knoevenagel condensation of 2,4-thiazolidinedione/rhodanine has been described. X-ray diffraction and transmission electron microscopy techniques revealed the formation ZnO nanobelts. Scanning electron microscopic observations indicate that the lengths of nanobelts are ranging from a few hundreds of micrometers to a few millimeters. Its use for the condensation of aldehydes and active methylene compounds under solvent free reaction condition at 90℃ afforded the corresponding products in excellent yields in minute time.

Hydrothermal Synthesis of V₃O₇.^.H₂O Nanobelts and Study of Their Electrochemical Properties

Vanadium oxide hydrate V3O7..H2O (H2V3O8) nanobelts have been synthesized by hydrothermal approach using V2O5 as vanadium source and phenolphthalein as structure-directing agent. Techniques X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared spectroscopy and nitrogen adsorption/desorption isotherms have been used to characterize the structure, morphology and composition of the nanobelts. The V3O7. H2O nanobelts are up to several hundreds of nanometers, the widths and thicknesses are 90 and 40 nm, respectively. The electroactivity of the nanobelts has been investigated. The as-synthesized material is promising for chemical and energy-related applications such as catalysts, electrochemical device and it may be applied in rechargeable lithium-ion batteries.

Tunable fabrication of single-crystalline CsPbI_(3) nanobelts and their application as photodetectors

Lead halide perovskites have received increasing attention recently as a candidate material in various optoelectronic areas because of their high performance as light absorbers.Herein,we report the growth of CsPbI_(3) nanobelts via a solution process.A single-crystalline CsPbI_(3) nanobelt with uniform morphology can be achieved by controlling the amount of PbI_(2).A single-crystalline CsPbI_(3) nanobelt possesses a mean width,length,and thickness of 100 nm,5μm,and 20 nm,respectively.In this work,photodetectors(PDs)based on individual CsPbI_(3) nanobelts are constructed and found to perform well with an external quantum efficiency and responsivity of 2.39×10^(5)% and 770 A/W,respectively.The PDs also show a high detectivity of up to 3.12×10^(12) Jones,which is at par with that of Si PDs.The PDs developed in this work exhibit great promise in various optoelectronic nanodevices.

Solvothermal Synthesis of α-Fe2O3 Porous Nanobelts and Their Enhanced Acetone-sensing Properties

Porous α-Fe2O3 nanobelts have been prepared via a solvothermal route and subsequent calcination. The as-prepared nanostructure was characterized by XRD, FESEM, TEM, N2 adsorption-desorption isotherms, etc. The α-Fe2O3 nanobelts presented obvious porous structures with the length of ca. 1~2μm, width of ca. 200~350 nm and thickness of ca. 30~60 nm. It was found that the assistance of inorganic additives played an important role in the shape control of α-Fe2O3 nanostructure. The gas-sensing performance of the fabricated sensor based on α-Fe2O3 nanobelts sample was also investigated, and the response towards 1000 ppm acetone can reach 24.4. In addition, the gas-sensing conductive mechanism of the sensor was also proposed.

Theoretical investigation on optical properties of Möbius carbon nanobelts in one-and two-photon absorption

The first successful synthesis of fully fused and fully conjugated Möbius carbon nanobelts(CNBs)has attracted considerable attention.However,theoretical calculations based on suchπ-conjugated Möbius CNB are still insufficient.Herein,we theoretically investigated molecular spectroscopy of Möbius CNBs without and with n-butoxy groups via visualization methods.The results show that the presence of n-butoxy groups can significantly affect Möbius CNBs’optical performance,changing electron-hole coherence and enhancing two-photon absorption cross-sections.Our work provides a deeper understanding of photophysical mechanisms of Möbius CNBs in one-and two-photon absorption and reveals possible applications on optoelectronic devices.

Ultrathin zirconium-porphyrin based nanobelts as photo-coupled electrocatalysis for CH_(4) oxidation to CO

The development of novel and effective methods for the activation of methane is fascinating,which offers a promising potential for the sustainable development of chemical industry and the mitigation of greenhouse effect.Here we successfully synthesize two-dimensional(2D)Zr/5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin(TCPP)ultrathin nanobelts(UNBs)as a high efficiency catalyst for methane(CH_(4))oxidation to carbon monoxide(CO).The Co-UNBs show well photo-coupled electrocatalytic performances for CH4 activation(CO production rates are 0.171 and 8.416 mmol·g−1·h−1 under dark/visible light,respectively).Density functional theory(DFT)calculations were performed to illustrate the mechanism of photoelectrocatalytic process and the high efficiency oxidation of CH4 to CO.Based on the ultrathin structure and highly efficient catalytic properties,this work provides a prospecting avenue for the design and synthesis of methane oxidation catalyst.

Activating MoO_(3) nanobelts via aqueous intercalation as a near-infrared type I photosensitizer for photodynamic periodontitis treatment

Although molybdenum trioxide nanomaterials have been widely explored as nanoagents for biomedical applications against bacteria through photothermal therapy,chemodynamic therapy,and catalytic therapy,their utilization as photosensitizers for photodynamic therapy(PDT)have been rarely reported so far.Herein,we report the activation of MoO_(3) nanobelts via aqueous co-intercalation of Na+and H_(2)O into their van der Waals gaps as a near-infrared Type I photosensitizer for photodynamic periodontitis treatment.The Na^(+)/H_(2)O intercalation of MoO_(3) nanobelts can shorten its length,generate rich oxygen vacancies,and enlarge its interlayer gaps.Such structural changes thus can induce the color change from white to dark blue with a strong near-infrared(NIR)absorption.When used as a photosensitizer,the I-MoO_(3−x) nanobelts exhibit much higher activities for the generation of superoxide radical(·O_(2)^(−))under an 808 nm laser irradiation than that of the pristine MoO_(3) nanobelts.Therefore,the prepared I-MoO_(3)−x nanobelts show a spectral antibacterial activity against Escherichia coli and Saccharomyces aureus,thus yielding a good clinical therapeutic effect on periodontitis.Our study proves that aqueous intercalation can be a simple but powerful strategy to activate layered MoO_(3) nanomaterials for high-performance PDT.

C–H…S Hydrogen Bond Assisted Supramolecular Encapsulation of Fullerenes with Nanobelts

Hydrogen-bonded capsules have been widely employed as supramolecular hosts for organic molecular guests.Encapsulation of fullerenes by capsules is relatively scarce,especially those that utilize sulfur atoms as hydrogen-bond acceptors.Herein,we describe,in both solution and solid state,a bowl-shaped nanobelt[8]cyclophenoxathiin 1a and its tetra-methylated derivative 1b that can form C–H⋯S hydrogen-bonded capsules induced by complexation with suitable fullerenes.1a strongly encapsulates C60,C70,or 6,6-phenyl-C61-butyric acid methyl ester(PC61BM)to form a 2∶1 ternary complex featuring 16 equatorial(sp2)C–H⋯S hydrogen bonds.A pseudorotaxane structure was further obtained for the complex of 1a with PC61BM.Conversely,a 1∶1 inclusion complex was observed for binding C60 or PC61BM with 1b indicating the reduced tendency to form capsules by introducing methyl groups into the belt.Surprisingly,the capsule-like structure was retained for the 1:2 complex of C70 with 1b as observed by the presence of multiple(sp3)C–H⋯S hydrogen bonds.The strong binding affinity and tailorable complexation mode enable further applications of nanobelts in fullerene chemistry.

Carbon Nanobelts:Brief History and Perspective

Carbon nanotubes(CNTs)are an emerging nanomaterial because of their outstanding performance in various applications.In recent years,the segment molecules of CNTs,referred to as carbon nanorings(CNRs)or carbon nanobelts(CNBs),have gained attention for their unique structures and properties,as well as their potential as seed molecules for the precise synthesis of CNTs.CNBs are rigid and thick segments of CNTs whose synthesis has been addressed by scientists fascinated by the uniqueness of CNBs long before the discovery of CNTs.After 60 years of efforts by synthetic chemists all over the world,the synthesis of the first CNB,(6,6)CNB,was achieved by our group in 2017.Since this milestone,diverse types of nanobelts have been synthesized through various synthetic routes,thereby demonstrating their photophysical,magnetic,and redox properties derived from rigid belt structures.The applications of CNBs have also been introduced recently.The formation of the host−guest complex,transformation to three-dimensional molecules,and measurement of conductivity have been reported for CNBs.This paper summarizes the brief history and perspective of CNBs.Further synthetic campaigns and aggressive application of CNBs would create novel and groundbreaking scenes in materials science.

Au nanorods decorated TiO_(2)nanobelts with enhanced full solar spectrum photocatalytic antibacterial activity and the sterilization file cabinet application

TiO_(2)photocatalysts have been widely studied and applied for removing bacteria,but its antibacterial efficiency is limited to the ultraviolet(UV)range of the solar spectrum.In this work,we use the gold(Au)nanorods to enhance the visible and near-infrared(NIR)light absorption of TiO_(2)NBs,a typical UV light photocatalyst,thus the enhancement of its full solar spectrum(UV,visible and NIR)photocatalytic antibacterial properties is achieved.Preliminary surface plasmon resonance(SPR)enhancement photocatalytic antibacterial mechanism is suggested.On one hand,transverse and longitudinal SPR of Au NRs is beneficial for visible and NIR light utilization.On the other hand,Au NRs combined with TiO_(2)NBs to form the heterostructure,which can improve the photogenerated carrier separation and direct electron transfer increases the hot electron concentration while Au NRs as the electron channel can well restrain charge recombination.finally produces the high yield of radical oxygen species and exhibits a superior antibacterial efficiency.Furthermore,we design a sterilization file cabinet with Au NR/TiO_(2)NB heterostructures as the photocatalytic coating plates.Our study reveals that Au NR/TiO_(2)NB heterostructure is a potential candidate for sterilization of bacteria and archives protection.

Surface-ligand protected reduction on plasmonic tuning of one-dimensional MoO_(3−x)nanobelts for solar steam generation

Sub-stoichiometric MoO_(3−x)nanostructures with plasmonic absorption via creating oxygen vacancies have attracted extensive attentions for many intriguing applications.However,the synthesis of one-dimensional(1D)plasmonic MoO_(3−x)nanostructures with widely tunable plasmonic absorption has remained a significant challenge because of their serious morphological destruction and phase change with increasing the concentration of oxygen vacancies.Here we demonstrate a surface-ligand protected reduction strategy for the synthesis of 1D MoO_(3−x)nanobelts with tunable plasmonic absorption in a wide wavelength range from 200 to 2,500 nm.Polyethylene glycol(PEG-400)is used as both the reductant to produce oxygen vacancies and the surface protected ligands to maintain 1D morphology during the formation process of MoO_(3−x)nanobelts,enabling the widely tunable plasmonic absorption.Owing to their broad plasmonic absorption and unique 1D nanostructure,we further demonstrate the application of 1D MoO_(3−x)nanobelts as photothermal film for interfacial solar evaporator.The surface-ligand protected reduction strategy provides a new avenue for the developing plasmonic semiconductor oxides with maintained particle morphology and thus enriching their wide applications.

Synthesis and Purple-Blue Emission of Antimony Trioxide Single-Crystalline Nanobelts with Elliptical Cross Section

Single-crystalline orthorhombic antimony trioxide(Sb_(2)O_(3))nanobelts with unique elliptical cross sections and purple-blue photoluminescence have been synthesized.The uniform Sb2O3 nanobelts are 400600 nm in width,2040 nm in thickness at the center and gradually become thinner to form sharp edges sub-5 nm in size,tens of micrometers in length,and with[001]as the preferential growth direction.Self-assembly of tens of nanobelts into three-dimensional(3-D)flower-like nanostructures has been observed.Analysis was performed by X-ray diffraction,energy-dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,scanning electron microscopy,high-resolution transmission electron microscopy,selected area electron diffraction,Raman spectroscopy,Fourier transform infrared spectroscopy,and photoluminescence spectroscopy.The Sb_(2)O_(3) nanobelts display intense purple-blue photoluminescence centred at 425 nm(~2.92 eV).The successful synthesis of nanobelts with elliptical cross sections may cast new light on the investigation of the property differences between nanobelts with rectangular cross sections and those with other cross section geometries.The Sb2O3 nanobelts can be used as effective purple-blue light emitters and may also be valuable for future nanodevice design.