Optical tweezers and associated manipulation tools in the far field have had a major impact on scientific and engineering research by offering precise manipulation of small objects. More recently, ...the possibility of performing manipulation with surface plasmons has opened opportunities not feasible with conventional far-field optical methods. The use of surface plasmon techniques enables excitation of hotspots much smaller than the free-space wavelength; with this confinement, the plasmonic field facilitates trapping of various nanostructures and materials with higher precision. The successful manipulation of small particles has fostered numerous and expanding applications. In this paper, we review the principles of and developments in plasmonic tweezers techniques, including both nanostructure-assisted platforms and structureless systems. Construction methods and evaluation criteria of the techniques are presented, aiming to provide a guide for the design and optimization of the systems. The most common novel applications of plasmonic tweezers, namely, sorting and transport, sensing and imaging, and especially those in a biological context, are critically discussed. Finally, we consider the future of the development and new potential applications of this technique and discuss prospects for its impact on science.
Micropopous chicken feather carbon (CFC) severing as electrode materials for the first time is prepared via the activation with KOH agent to different extents. The structure and electrochemical ...properties of CFC materials are characterized with N2 adsorption/desorption measurements, X-ray diffraction (XRD), transmission electron microscope (TEM), cyclic voltammetry (CV), galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy (EIS). The obtained results show that CFC activated by KOH with KOH/CFC weight ratio of 4/1 (CFCA4) possesses the specific surface area of 1839 m2 g−1, average micropore diameter of 1.863 nm, and exhibits the highest initial specific capacitance of 302 F g−1 at current density of 1 A g−1 in 1 M H2SO4, and that even after 5000 cycles, CFCA4 specific capacitance is still as high as 253 F g−1. Furthermore, CFCA4 also delivers specific capacitance of 181 F g−1 at current density of 5 A g−1 and 168 F g−1 at current density of 10 A g−1. Accordingly, the microporous activated carbon material derived from chicken feather provides favorable prospect in electrode materials application in supercapacitors.
► Chicken feather carbon is acted as electrode materials for the first time. ► Chicken feather originates from essentially free renewable livestock biowaste. ► There are abundant micropores for the activated chicken feather carbon. ► The activated carbon shows the excellent electrochemical properties.
Hierarchically porous carbons (HPCs) have been prepared by sol–gel self-assembly technology with nickel oxide and surfactant as the dual template. The porous carbons are further activated by nitric ...acid. The electrochemical behaviors of supercapacitors using HPCs as electrode material in different aqueous electrolytes, e.g., (NH4)2SO4, Na2SO4, H2SO4 and KOH are studied by cyclic voltametry, galvanostatic charge/discharge, cyclic life, leakage current, self-discharge and electrochemical impedance spectroscopy. The results demonstrate that the supercapacitors in various electrolytes perform definitely capacitive behaviors; especially in 6 M KOH electrolyte the supercapacitor represents the best electrochemical performance, the shortest relaxation time, and nearly ideal polarisability. The energy density of 8.42 Wh kg−1 and power density of 17.22 kW kg−1 are obtained at the operated voltage window of 1.0 V. Especially, the energy density of 11.54 Wh kg−1 and power density of 10.58 kW kg−1 can be achieved when the voltage is up to 1.2 V.
► Comparable electrochemical performances in various aqueous electrolytes. ► In 6.0 M KOH the supercapacitor performs the best electrochemical behaviors. ► The highest energy density of the supercapacitor in 6.0 M KOH is 11.54 Wh kg−1. ► In 6.0 M KOH the supercapacitor has the shortest relaxation time of 0.62 s.
Display omitted
•Dual stabilized architecture of hollow Si@TiO2@C nanosphere is synthesized successfully.•The material presents excellent cycling performance and rate capability.•The enhanced ...properties are ascribed to the uniform TiO2 shell and C layer.
The hollow Si nanospheres modified by the mechanically robust titanium dioxide (TiO2) shell and the uniform carbon layer are intentionally designed and successfully prepared as the anode active material of high performance lithium-ion batteries. The effects of the robust TiO2 shell and the uniform carbon layer on the structure and electrochemical performances for the Si@TiO2@C nanospheres are studied in detail by X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffraction and charge/discharge tests. The results show that the hollow structure of the Si core can spontaneously absorb the huge volume expansion stress, the robust TiO2 shell is used as a compact fence to promote the expansion towards the interior of the Si cavity instead of the exterior in the processes of charge/discharge, and the uniform carbon layer can effectively enhance the electrical conductivity and further control the integrity and stability of the well-wrapped core-shell-shell framework. Typically, the resultant hollow Si@TiO2@C nanospheres exhibit a high initial discharge capacity of 2557.1 mAh g−1 with coulombic efficiency of 86.06% as well as a large recuperative discharge capacity of 1270.3 mAh g−1 after 250 cycles at 1 A g−1 with a mean coulombic efficiency of 99.53%. Therefore, the hollow Si@TiO2@C nanospheres prepared by one-step sol-gel coating process show outstanding electrochemical properties and are considered as a prospective candidate to the adhibitions of the anode material for new generation power LIBs.
Based on the conversion and alloying reactions, antimony sulfide (Sb2S3) with a theoretical discharge specific capacity of 946 mAh g−1 is a hopeful anode material for lithium/sodium ion batteries. ...Nevertheless, the poor electronic conductivity of Sb2S3 and the serious volume expansion during alloying reaction bring about the rapid capacity fading, which severely hinder its practical application. The design of morphology/structure and/or combining with carbon materials is the common strategies to address these issues. Herein, a simple electrospinning technology coupled with hydrothermal reaction is employed to synthesize the Sb2S3/carbon-silicon oxide (Sb2S3/CS) nanofibers for the first time. The obtained Sb2S3/CS nanofibers show superior lithium/sodium storage properties. Specifically, the Sb2S3/CS electrode maintains a high discharge specific capacity of 566 mAh g−1 under 200 mA g−1 after 200 cycles in lithium-ion batteries. For sodium storage, the Sb2S3/CS electrode obtains a discharge specific capacity of 321 mAh g−1 under 200 mA g−1 over 200 cycles. One-dimensional Sb2S3/CS nanofibers with good electronic conductivity accelerate the transport of ions and electrons, and effectively buffer the volume change of Sb2S3 nanoparticles during electrochemical reaction process, bringing about the excellent electrochemical properties.
•Sb2S3/CS nanofibers were synthesized by electrospinning and hydrothermal method.•The formation of Sb2S3/CS is reducing SbOx to Sb and transforming Sb to Sb2S3.•The fine 1D fiber structure can facilitate the transport of ions and electrons.•The Sb2S3/CS nanofibers have excellent lithium and sodium storage properties.
The cornlike ordered mesoporous silicon (OM-Si) particles modified by the nitrogen-doped carbon layer (OM-Si@NC) are successfully fabricated and used as the anode of lithium-ion battery (LIBs). The ...influences of the N-doped carbon layer on the structure and electrochemical properties of the OM-Si@NC composite are detailedly investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectroscopy (XPS), and charge/discharge tests. The results reveal that the amorphous N-doped carbon layer can offer the abundant conductive pathways for fast lithium ion transportation and electron transfer, which not only leads to a high specific capacity under high ampere density but also serves as a structural barrier maintaining the whole integrity and settling the mechanical breaking due to the huge volume changes of Si host. Therefore, the as-synthesized OM-Si@NC composite exhibits a high original discharge capacity of 2548 mA h g–1 under 0.2 A g–1 as well as a large reversible capacity of 1336 mA h g–1 under 1 A g–1 after 200 circles. The OM-Si@NC composite prepared by a relatively simple and feasible synthesis method shows excellent electrochemical performances and turns out to be promising for the application of high power LIBs.
A kind of nitrogen-doped activated microporous carbon sphere/sulfur composite (NAMCS/S) is deliberately designed and prepared via a controllable solvothermal method and a liquid phase in-situ sulfur ...deposition technology. The structure characteristic and composition analysis of samples are conducted with X-ray photoelectron spectroscopy (XPS), elemental analysis (EA), field-emission scanning electron microscopy (FESEM) and high resolution transmission electron microscope (HRTEM). The electrochemical performances are characterized by galvanostatic charge-discharge (GCD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. The results show that the nitrogen-doped activated microporous carbon spheres (NAMCS) present uniform spherical morphology, abundant nitrogen content of 9.64 wt%, and large specific surface areas of 1578.6 m2/g. Compared with the activated microporous carbon sphere/sulfur (AMCS/S) composite, the NAMCS/S composite with same sulfur loading of 64 wt% can deliver a higher initial capacity of 1004.6 mAh/g and a stable capacity retention of 79.1% after 100 cycles at 0.1 C rate as well as a remarkable Coulombic efficiency of 93% and relative low capacity decay of 0.2% per cycle. These effective improvements are attributed to the change of surface physicochemical property, chemical interaction between nitrogen functionality and polysulfides and the physical adsorption of abundant microporous structure.
•A novel NAMCS/S composite is synthesized via a controllable solvothermal route.•NAMCS possess strong chemical and physical adsorption to immobilize polysulfides.•The nitrogen-doped can be beneficial to excellent cycling performance.
Polypyrrole (PPy)/carbon aerogel (CA) composite materials with different PPy contents are prepared by chemical oxidation polymerization through ultrasound irradiation and are used as active electrode ...material for supercapacitor. The morphology of PPy/CA composite is examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that PPy is deposited onto the surface of CA. As evidenced by cyclic voltammetry, galvanostatic charge/discharge test and EIS measurements, PPy/CA composites show superior capacitive performances to CA, moreover, the results based on cyclic voltammograms show that the composite material has a high specific capacitance of 433
F
g
−1, while the capacitance of CA electrode is only 174
F
g
−1. Although the supercapacitor used PPy/CA as active electrode material has an initial capacitance loss due to the instability of PPy, the specific capacitance after 500 cycles stabilizes nearly at a fixed value.
The spherical lithium-rich cathode material with a layered-spinel hybrid structure is successfully synthesized and coated by polyaniline (PANI). The spherical material with layered-spinel hybrid ...structure is firstly prepared via the hydrothermal method, and then the conducting PANI is coated on the surface of the as-prepared spherical particle through an in-situ polymerization. Based on the analysis of scanning electron microscope (SEM), transmission electron microscope (TEM), high rate transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED), it can be found that the size distribution of the spherical particles modified by PANI are about ∼1 μm, meanwhile the average thickness of the PANI layer on the surface of each particle is about 6.3 nm. The electrochemical performance of the spherical lithium-rich cathode material modified by PANI is apparently improved, the capacity retention is still 92.4% after 200 cycles at a rate of 0.5 C. The discharge capacities at 0.1 C and 10 C are as high as 302.9 mAh g−1 and 146.2 mAh g−1, respectively. Therefore, the modification of PANI for the spherical lithium-rich cathode material with a layered-spinel hybrid structure will be a promising technical route for the application with high capacity, long cycle life and good safety.
•The spherical lithium-rich cathode material is successfully synthesized.•The material has a spinel-layered hybrid structure inside and a PANI layer outside.•The material shows an excellent cycle stability and improved coulombic efficiency.•The improved performances are attributed to the spinel structure and the PANI layer.
The fluoride ion batteries (FIBs) based on “fluoride ion shuttle” have received extensive attention due to their high energy density, safety and thermal stability. Although the FIBs show above ...advantages, several challenges still remain to be tackled, e.g., so far reported solid-state FIBs can only operate at the high temperature like 150 °C and above. Herein, the SnF2-based fluoride ion conductors MSnF4 (M = Ba, Pb) are prepared through high-energy ball-milling and annealing as solid electrolytes in solid-state FIBs. The morphology and structure of the solid electrolytes are studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Especially, the fluoride ion transporting characteristics of BaSnF4 and PbSnF4 solid electrolytes are investigated by impedance spectroscopy (EIS). The results show that the high RT ionic conductivities of BaSnF4 (2.02 × 10−4 S cm−1) and PbSnF4 (5.44 × 10−4 S cm−1) make it possible to prepare the RT solid-state FIBs with Sn as an anode and BiF3 as a cathode. The initial discharging capacities of the Sn/PbSnF4/BiF3 cell and the Sn/BaSnF4/BiF3 cell studied by galvanostatic charge/discharge cycling are 175 mAh g−1 and 125 mAh g−1 at RT, respectively. The structural and chemical characterization of the BiF3 composites and the Sn composites before and after discharge is examined in detail by X-ray diffraction (XRD) in order to explicate the charge/discharge behavior of the RT solid-state FIBs.
•BaSnF4 and PbSnF4 solid electrolytes are manufactured via high-energy ball-milling.•The ionic conductivity of BaSnF4 is 2.02 × 10−4 S cm−1 and PbSnF4 solid electrolyte is 5.44 × 10−4 S cm−1 at RT.•The activation energies for BaSnF4 and PbSnF4 solid electrolytes are 0.23 eV and 0.26 eV.•Two novel solid-state FIB systems with BaSnF4 or PbSnF4 solid electrolyte are discussed.•At RT, Sn/BiF3 systems exhibit first discharge capacity of 175 mAh g−1 and 125 mAh g−1.
PDF
