Tea-derived carbon materials as anode for high-performance sodium ion batteries

Sodium-ion batteries (SIB) have attracted widespread attention in large-scale energy storage fields owing to the abundant reserve in the earth and similar properties of sodium to lithium. Biomass-based carbon materials with low-cost, controllable structure, simple processing technology, and environmental friendliness tick almost all the right boxes as one of the promising anode materials for SIB. Herein, we present a simple novel strategy involving tea tomenta biomass-derived carbon anode with enhanced interlayer carbon distance (0.44 nm) and high performance, which is constructed by N,P co-doped hard carbon (Tea-1100-NP) derived from tea tomenta. The prepared Tea-1100-NP composite could deliver a high reversible capacity (326.1 mAh/g at 28 mA/g), high initial coulombic efficiency (ICE = 90% at 28 mA/g), stable cycle life (262.4 mAh/g at 280 mA/g for 100 cycles), and superior rate performance (224.5 mAh/g at 1400 mA/g). Experimental results show that the excellent electrochemical performance of Tea-1100-NP due to the high number of active N,P-containing groups, and disordered amorphous structures provide ample active sites and increase the conductivity, meanwhile, large amounts of microporous shorten the Na⁺ diffusion distance as well as quicken ion transport. This work provides a new type of N,P co-doped high-performance tomenta-derived carbon, which may also greatly promote the commercial application of SIB.     

A selenium-doped carbon anode of high performance for lithium ion batteries

Journal of Solid State Electrochemistry - The strong demand on high-performance lithium ion batteries has brought up an attention upsurge in the research society and the commercial market. Carbon...     

Synthesis of phosphorus-doped soft carbon as anode materials for lithium and sodium ion batteries

Phosphorus-doped soft carbon was synthesized by a facile phosphoric acid-assisted route. It is found that the phosphorus-doped soft carbon used as lithium ion battery anode exhibits a high reversible capacity of 333.6 mA h g^–1 with the first cycle coulombic efficiency of 87.0% at the current density of 30 mA g^–1. When used as sodium ion battery anode, it also shows great storage performance, with a reversible capacity of 121.3 mA h g^–1 with an initial coulombic efficiency of 65.0% at the current density of 10 mA g^–1. Besides, good rate capability and stable cycling performance are also observed for both lithium and sodium ion batteries, indicating potential of their application in large-scale storage devices.

     

Fe2O3 xerogel used as the anode material for lithium ion batteries with excellent electrochemical performance

A new strategy was applied to synthesise a porous nanostructure of α-Fe(2)O(3) xerogel assembled from nanocrystalline particles (～5 nm) with abundant mesopores (～3 nm) using a hydrothermal method. The α-Fe(2)O(3) xerogel exhibits excellent cycling performance (up to 1000 cycles) and rate capability (reversible discharging capacity 280 mAh g(-1) at 10 C) as a potential anode for high power lithium-ion batteries.     

Sulfur-doped carbon coating on K2Ti6O13 nanowires as anode of sodium ion batteries

Journal of Solid State Electrochemistry - In this work, we synthesized K2Ti6O13 nanowires coated with sulfur-doped carbon for the first time, with fulvic acid and cystine as the carbon source,...     

V2O5/rGO arrays as potential anode materials for high performance sodium ion batteries

Journal of Solid State Electrochemistry - Herein, we successfully deposit V2O5 nanobelt arrays on Ni foam uniformly coated with reduced graphene oxides (rGO), to manufacture V2O5/rGO arrays...     

Hard carbon derived from cellulose as anode for sodium ion batteries:Dependence of electrochemical properties on structure

Cellulose, the most abundant organic polymer on Earth, is a sustainable source of carbon to use as a negative electrode for sodium ion batteries. Here, hard carbons(HC) prepared by cellulose pyrolysis were investigated with varying pyrolysis temperature from 700 °C to 1600 °C. Characterisation methods such as Small Angle X-ray Scattering(SAXS) measurements and N_2 adsorption were performed to analyse porosity differences between the samples. The graphene sheet arrangements were observed by transmission electron microscopy(TEM): an ordering of the graphene sheets is observed at temperatures above 1150 °C and small crystalline domains appear over 1400 °C. As the graphene sheets start to align, the BET surface area decreases and the micropore size increases. To correlate hard carbon structures and electrochemical performances, different tests in Na//HC cells with 1 M NaPF_6 ethylene carbonate/dimethyl carbonate(EC/DMC) were performed. Samples pyrolysed from 1300 °C to 1600 °C showed a 300 m Ah/g reversible capacity at C/10 rate(where C = 372 mA/g) with an excellent stability in cycling and a very good initial Coulombic efficiency of up to 84%. Furthermore, hard carbons showed an excellent rate capability where sodium extraction rate varies from C/10 to 5C. At 5C more than 80% of reversible capacity remains stable for hard carbons synthesized from 1000 °C to 1600 °C.     

Inside the failure mechanism of tin oxide as anode for sodium ion batteries

Journal of Solid State Electrochemistry - The conversion-alloying compounds have been identified as promising anode materials for sodium ion batteries (SIBs). One of them, SnO2, with an enormous...     

A facile bubble-assisted synthesis of porous Zn ferrite hollow microsphere and their excellent performance as an anode in lithium ion battery

Pure porous hollow Zn ferrite (ZnFe₂O₄) microspheres have been successfully synthesized by a facile bubble assisted method in the presence of ammonium acetate (NH₄Ac) as an anode material in lithium ion battery. The shape, size, and morphology of Zn ferrite are investigated by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Furthermore, the probable bubble-assisted formation mechanism of porous hollow Zn ferrite spheres based on the experimental results is proposed. With the porous hollow structure, the obtained pure Zn ferrite particle as an anode in lithium ion battery demonstrates high capacity and excellent cycle ability. The high initial discharge specific capacity is approximately 1,400 mAh g^?1 and a reversible specific capacity approaches 584 mAh g^?1 after 100 cycles at a constant current density of 100 mA g^?1. The excellent electrochemical performance of the as-prepared Zn ferrite could be attributed to the special structure with which the volume expansion and pulverization of the particles became increasingly reduced.     

Superior storage performance of carbon nanosprings as anode materials for lithium-ion batteries

Carbon nanosprings (CNSs) with spring diameter of ～140 nm, carbon ring diameter of ～100 nm and pitch distance of ～150 nm, synthesized by using a catalytic chemical vapor deposition technology, have been investigated for potential applicability in lithium batteries as anode materials. The electrochemical results demonstrate that the present CNSs are superior anode materials for rechargeable lithium-ion batteries with high-rate capabilities, as well as long-term cycling life. At a current density as high as 3 A g^?1, CNSs can still deliver a reversible capacity of 160 mA h g^?1, which is about six times larger than that of graphite and three times larger than that of multi-wall carbon nanotubes under the same current density. After hundreds of cycles, there is no significant capacity loss for CNSs at both low and high current densities. The much improved electrochemical performances could be attributed to the nanometer-sized building blocks as well as the unusual spring-like morphology.     

A novel mesoporous carbon-silica-titania nanocomposite as a high performance anode material in lithium ion batteries

An ordered mesoporous carbon-silica-titania material was prepared using the tetra-constituents co-assembly method. As regards its anode performance in lithium ion batteries, the composite material anode exhibited a high capacity (875 mAh g(-1)), a higher initial efficiency (56%) and an improved rate.     

Porous Si coated with S-doped carbon as anode material for lithium ion batteries

A novel porous Si/S-doped carbon composite was prepared by a magnesiothermic reaction of mesoporous SiO₂, subsequently coating with a sulfur-containing polymer-poly(3,4-ethylene dioxythiophene), and a post-carbonization process. The as-prepared Si composite was homogeneously coated with disordered S-doped carbon with 2.6 wt.%?S in the composite and retained a high surface area of 58.8 m²?g^?1. The Si/S-doped carbon composite exhibited superior electrochemical performance and long cycle life as an anode material in lithium ion cells, showing a stable reversible capacity of 450 mAh g^?1 even at a high current rate of 6,000 mA?g^?1.     

Facile fabrication of MoP nanodots embedded in porous carbon as excellent anode material for potassium-ion batteries

Molybdenum phosphide(MoP),owing to its abundant reserve and high theoretical capacity,is regarded as a promising anode material for potassium-ion batteries.However,it still suffers from the problems of acute volume expansion and weak diffusion kinetics.This study reports a simple method to synthesize a composite of molybdenum phosphide and porous carbon(MoP@PC)through simple mixing and annealing treatment.In the MoP@PC,lots of MoP nanodots with an average diameter of about 4 nm uniformly embedded in the petal-like porous carbon.The MoP@PC shows reversible capacities of 330 mAh g^-1 at100 mA g^-1 after 100 cycles,and ultra-long cycling stability with a capacity of 240 mAh g^-1 after 1000 cycles at 1 A g^-1 and 161 mAh g^-1 after 1000 cycles at 5 A g^-1.The structure of MoP@PC after charging-discharging cycles is also investigated by high resolution transmission electron microscope(HRTEM)and the result shows that MoP can still maintain the nanodot morphology without any agglomeration after 1000 cycles at 5 A g^-1.The storage mechanism of potassium ions was studied as well,which reveals that MoP and potassium ion have a conversion reaction.     

Potassium ion anode versus sodium ion anode: Potato starch residue derived carbon material as a case study

Journal of Solid State Electrochemistry - Herein, potato starch residue derived carbon materials (PSRC) and KOH activated PSRC (denoted as APSRC) are successfully realized in this work....     

Facile synthesis of silicon nanoparticles inserted into graphene sheets as improved anode materials for lithium-ion batteries

Silicon nanoparticles have been successfully inserted into graphene sheets via a novel method combining freeze-drying and thermal reduction. The as-obtained Si/graphene nanocomposite exhibits remarkably enhanced cycling performance and rate performance compared with bare Si nanoparticles for lithium-ion batteries.     

TiC/C core/shell nanowires arrays as advanced anode of sodium ion batteries

High-perfo rmance anodes of sodium ion batteries(SIBs)largely depends on rational architecture design and binder-free smart hybridization.Herein,we report TiC/C core/shell nanowires arrays prepared by a one-step chemical vapor deposition(CVD)method and apply it as the anode of SIBs for the first time.The conductive TiC core is intimately decorated with carbon shell.The as-obtained TiC/C nanowires are homogeneously grown on the substrate and show core/shell heterostructure and porous architecture with high electronic conductivity and reinforced stability.Owing to these merits,the TiC/C electrode displays good rate performance and outstanding cycling performance with a capacity of 135.3 mAh/g at 0.1 A/g and superior capacity retention of 90.14%after 1000 cycles at 2 A/g.The reported strategy would provide a promising way to construct binder-free arrays electrodes for sodium ion storage.     

Dealloying-induced dual-scale nanoporous indium-antimony anode for sodium/potassium ion batteries

InSb alloy is a promising candidate for sodium/potassium ion batteries(SIBs/PIBs) but challenged with achieving high performance by dramatic volumetric changes. Herein, nanoporous(np)-InSb with dualscale phases(cubic/hexagonal(C/H)-InSb) was fabricated by chemical dealloying of ternary Mg-In-Sb precursor. Operando X-ray diffraction(XRD) and ex-situ characterizations well rationalize the dealloying/alloying mechanisms and the formation of dual-scale microstructures/phases. As an anode for SIB/PIB...     

Electrochemical reduction of nano-SiO2 in hard carbon as anode material for lithium ion batteries

A composite of silica (SiO₂) and hard carbon was prepared by hydrothermal reaction. Special attention was paid to the characterization of the possible electrochemical reduction of nano-SiO₂ in the composite. Evidence by solid-state nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) and high lithium storage capacity of the composite prove the electrochemical reduction of nano-SiO₂ and the formation of Li₄SiO₄ and Li₂O as well as Si in the first-discharge. The reversible lithium storage capacity of the nano-SiO₂ is as high as 1675 mAh/g.     

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].     

InP as new anode material for lithium ion batteries

InP thin film has been successfully fabricated by pulsed laser deposition (PLD) and was investigated for its electrochemistry with lithium for the first time. InP thin film presented a large reversible discharge capacity around 620 mAh g^?1. The reversibility of the crystalline structure and electrochemical reaction of InP with lithium were revealed by using ex situ XRD and XPS measurements. The high reversible capacity and stable cycle of InP thin film electrode with low overpotential made it one of the promise energy storage materials for future rechargeable lithium batteries.